Home

NI-VXI User Manual

Contents

1. 3 36 Programming Considerations 3 38 WaitForSignal Considerations 3 39 DefaultSignalHandler 3 40 DisableSignalInt 3 40 EnableSignalInt 3 40 GetSignalHandler 3 41 RouteSignal 3 41 SetSignalHandler 3 41 SignalDeq 3 42 SignalEnq 3 42 SignalJam 3 42 WaitForSignal 3 42 Table of Contents National Instruments Corporation ix NI VXI User Manual V
2. 1 5 Chapter 2 Introduction to the NI VXI Functions Function Groups 2 1 VXI VME Function Groups 2 1 VXI Only Function Groups 2 3 Calling Syntax 2 3 LabWindows CVI 2 4 Type Definitions 2 4 Input Versus Output Parameters 2 4 Return Values and System Errors 2 5 Table of Contents NI VXI User Manual vi National Instruments Corporation Multiple Mainframe Support 2 5 Controllers 2 5 The extender and controller Parameters 2 7 Using NI VXI
3. 3 64 GetBusErrorHandler 3 64 GetSoftResetHandler 3 65 GetSysfailHandler 3 65 GetSysresetHandler 3 65 SetACfailHandler 3 65 SetBusErrorHandler 3 65 SetSoftResetHandler 3 66 SetSysfailHandler 3 66 SetSysresetHandler 3 66 VXI VMEbus Extender Functions 3 67 MapECLtrig 3 67 MapTTLtrig 3 67 MapUtilBus
4. 3 56 Map Trigger Functions 3 56 MapTrigToTrig 3 56 UnMapTrigToTrig 3 57 Source Trigger Functions 3 57 SrcTrig 3 57 Trigger Configuration Functions 3 58 TrigAssertConfig 3 58 TrigCntrConfig 3 58 TrigExtConfig 3 58 TrigTickConfig 3 59 System Interrupt Handler Functions 3 59 AssertSysreset 3 60 DefaultACfailHandler
5. 3 21 WSSnoResp 3 22 WSSrd 3 22 WSSsendResp 3 22 WSSwrt 3 22 High Level VXI VMEbus Access Functions 3 23 Programming Considerations 3 23 VXIin 3 24 VXIinReg 3 24 VXImove 3 24 Table of Contents NI VXI User Manual viii National Instruments Corporation VXIout 3 25 VXIoutReg 3 25 Low Level VXI VMEbus Access Functions 3 26 Progra
6. 2 9 Header Files 2 9 The datasize h File 2 9 The busacc h File 2 10 The devinfo h File 2 10 The Beginning and End of an NI VXI Program 2 10 System Configuration Tools 2 11 Word Serial Communication 2 13 Master Memory Access 2 14 Slave Memory Access 2 16 Interrupts and Signals 2 17 Triggers 2 19 Chapter 3 Software Overview System Configuration Functions 3 1 CloseVXIlibrary 3 2 CreateDevInfo
7. 3 2 FindDevLA 3 2 GetDevInfo 3 3 GetDevInfoLong 3 3 GetDevInfoShort 3 3 GetDevInfoStr 3 3 InitVXIlibrary 3 4 SetDevInfo 3 4 SetDevInfoLong 3 4 SetDevInfoShort 3 5 SetDevInfoStr 3 5 Commander Word Serial Protocol Functions 3 5 Programming Considerations 3 7 Interrupt Service Routine Support 3 7 Single Tasking Operating System S
8. 3 60 DefaultBusErrorHandler 3 60 Table of Contents NI VXI User Manual x National Instruments Corporation DefaultSoftResetHandler 3 61 DefaultSysfailHandler 3 61 DefaultSysresetHandler 3 62 DisableACfail 3 62 DisableSoftReset 3 62 DisableSysfail 3 62 DisableSysreset 3 63 EnableACfail 3 63 EnableSoftReset 3 63 EnableSysfail 3 63 EnableSysreset 3 64 GetACfailHandler
9. 3 19 GetWSSLcmdHandler 3 19 GetWSSrdHandler 3 19 GetWSSwrtHandler 3 19 RespProtError 3 19 SetWSScmdHandler 3 19 SetWSSEcmdHandler 3 20 SetWSSLcmdHandler 3 20 SetWSSrdHandler 3 20 SetWSSwrtHandler 3 20 WSSabort 3 21 WSSdisable 3 21 WSSenable 3 21 WSSLnoResp 3 21 WSSLsendResp
10. 3 50 VXIintAcknowledgeMode 3 50 VXI Trigger Functions 3 51 Capabilities of the National Instruments Triggering Hardware 3 52 External Controller VXI MXI 1 Trigger Capabilities 3 53 Embedded External MXI 2 and Remote Controller Trigger Capabilities 3 54 Acceptor Trigger Functions 3 54 AcknowledgeTrig 3 55 DefaultTrigHandler 3 55 DefaultTrigHandler2 3 55 DisableTrigSense 3 55 EnableTrigSense 3 55 GetTrigHandler 3 56 SetTrigHandler 3 56 WaitForTrig
11. Register based device instrument drivers Non VXI device instrument drivers Accessing device dependent registers on any type of VXI VME device Implementing shared memory protocols Low level and high level access to the VXI VMEbus as the NI VXI interface defines them are very similar in nature Both sets of functions can perform direct reads of and writes to any VXI VMEbus address space with any privilege state or byte order However the two interfaces have different emphases with respect to user protection error checking and access speed Low level VXI VMEbus access is the fastest access method in terms of overall throughput to the device for directly reading or writing to from any of the VXI VMEbus address spaces with random memory accesses Under many platforms the high level operation VXImove provides the fastest access in terms of block moves As such however it is more detailed and leaves more issues for the application to resolve You can use these functions to obtain pointers that are directly mapped to a particular VXI VMEbus address with a particular VXI VME access privilege and byte ordering You need to consider a number of issues when using the direct pointers You need to determine bounds for the pointers Based on the methods in which a particular hardware platform sets up access to VXI VME address spaces using more than one pointer can result in conflicts Your application
12. 3 12 WSsetTmo 3 13 WStrg 3 13 WSwrt 3 13 WSwrtf 3 14 Servant Word Serial Protocol Functions 3 14 Programming Considerations 3 15 DefaultWSScmdHandler 3 17 DefaultWSSEcmdHandler 3 17 DefaultWSSLcmdHandler 3 17 DefaultWSSrdHandler 3 18 DefaultWSSwrtHandler 3 18 GenProtError 3 18 GetWSScmdHandler 3 18 GetWSSEcmdHandler
13. A 8 National Instruments Corporation xiii NI VXI User Manual About This Manual This manual describes in detail the features of the NI VXI software and the VXI VME function calls in the C C and BASIC languages Organization of This Manual The NI VXI User Manual for C C and BASIC is organized as follows Chapter 1 Overview of NI VXI introduces you to the concepts of VXI VME eXtensions for Instrumentation VME MXI Multisystem eXtension Interface and their relationship to the NI VXI application programmer s interface API Chapter 2 Introduction to the NI VXI Functions introduces you to the NI VXI functions and their capabilities Additional discussion is provided for each function s parameters and includes descriptions of the application development environment This chapter concludes with an overview on using the NI VXI application programming interface Chapter 3 Software Overview describes the C C and BASIC usage of VXI and VME functions and briefly describes each function Functions are listed alphabetically in each functional group Appendix A Function Classification Reference contains two tables you can use as a quick reference Table A 1 Function Listing by Group lists the NI VXI functions by their group association This arrangement can help you determine easily which functions are available within each group Table A 2 Function Listing by Name lists each function a
14. bus Remote Controller and Extender Remote Controller and Extender External Controller Extender Only Figure 2 2 An External Controller Connected Using MXI 2 to a Number of Remote Controllers The extender and controller Parameters In NI VXI some functions require a parameter named extender or controller Since some extenders act as controllers there is often confusion concerning what logical addresses should be passed to these functions The extender parameter is the logical address of a mainframe extender on which the function should be performed Usually functions with an extender parameter involve the mapping of interrupt lines or trigger lines into or out of a frame The controller parameter is the logical address of an embedded external extending or remote controller Usually functions with a controller parameter involve sourcing or sensing particular interrupts or triggers in a frame According to the definitions of the different types of controllers the only valid logical addresses for the controller parameter are The external or embedded controller on which the program is running A parent side VXI MXI 2 or VME MXI 2 in a frame Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 8 National Instruments Corporation Most functions that take a controller parameter will allow you to pass 1 as the logical address This selects the default controller for the system Noti
15. 3 68 MapVXIint 3 68 Appendix A Function Classification Reference Appendix B Customer Communication Glossary Index Table of Contents National Instruments Corporation xi NI VXI User Manual Figures Figure 1 1 VXI Configuration Registers 1 2 Figure 1 2 VXI Software Protocols 1 3 Figure 2 1 An Embedded Controller Connected to Other Frames via Mainframe Extenders Using MXI 2 2 6 Figure 2 2 An External Controller Connected Using MXI 2 to a Number of Remote Controllers 2 7 Figure 3 1 Preemptive Word Serial Mutual Exclusion Per Logical Address 3 9 Figure 3 2 NI VXI Servant Word Serial Model 3 16 Figure 3 3 NI VXI Interrupt and Signal Model 3 39 Figure 3 4 NI VXI Interrupt and Signal Model 3 45 Tables Table A 1 Function Listing by Group A 1 Table A 2 Function Listing by Name
16. GetPrivilege Low Level VXI VMEbus Access GetSignalHandler VXI Signal GetSoftResetHandler System Interrupt Handler GetSysfailHandler System Interrupt Handler GetSysresetHandler System Interrupt Handler GetTrigHandler Triggers GetVXIbusStatus Low Level VXI VMEbus Access GetVXIbusStatusInd Low Level VXI VMEbus Access GetVXIintHandler VXI VME Interrupt GetWindowRange Low Level VXI VMEbus Access GetWSScmdHandler Servant Word Serial Protocol GetWSSEcmdHandler Servant Word Serial Protocol GetWSSLcmdHandler Servant Word Serial Protocol GetWSSrdHandler Servant Word Serial Protocol GetWSSwrtHandler Servant Word Serial Protocol Appendix A Function Classification Reference NI VXI User Manual A 10 National Instruments Corporation Table A 2 Function Listing by Name Function Group VXI VME C C BASIC InitVXIlibrary System Configuration MapECLtrig VXI VMEbus Extender MapTrigToTrig Triggers MapTTLtrig VXI VMEbus Extender MapUtilBus VXI VMEbus Extender MapVXIAddress Low Level VXI VMEbus Access MapVXIAddressSize Low Level VXI VMEbus Access MapVXIint VXI VMEbus Extender ReadMODID Local Resource Access RespProtError Servant Word Serial Protocol RouteSignal VXI Signal RouteVXIint VXI VME Interrupt SetACfailHandler System Interrupt Handler SetBusErrorHandler System Interrupt Handler SetByteOrder Low Level VXI VMEbus Access SetConte
17. VXI VME Interrupts 1 7 Hardware NI VXI Software User Application VXIintHandlers SignalHandlers NI VXI base Interrupt Service Routines ISR Local VXI Signals EnableSignalInt DisableSignalInt RouteSignal EnableVXIint DisableVXIint EnableVXItoSignalInt DisableVXItoSignalInt SetVXIintHandler GetVXIintHandler DefaultVXIintHandler SignalEnq User ISRs 1 per VXI VME interrupt level 1 per logical address SetSignalHandler GetSignalHandler DefaultSignalHandler Signal Processor Signal Queue WaitForSignal If signal not on queue enable monitor block till received else SignalDeq return signal mask SignalDeq uint16 signal SignalEnq SignalDeq SignalJam uint16 statusId WaitForSignal uint16 level uint32 statusId uint16 signal uint16 signal Get Signal Get Status Id VXIintAcknowledgeMode Figure 3 3 NI VXI Interrupt and Signal Model WaitForSignal Considerations The function WaitForSignal can be used to suspend a process function until a particular VXI signal or one of a set of signals arrives Any signals to be waited on should be routed to the global signal queue If the RouteSignal function has specified for the signal to be handled by the interrupt service routine the WaitForSignal call will not detect that the signal and the process function may block until a timeout WaitForSignal attempts to dequeue a signa
18. VXIinLR VXImemAlloc VXImemCopy VXImemFree VXIoutLR VXI Signal DefaultSignalHandler DisableSignalInt EnableSignalInt GetSignalHandler RouteSignal SetSignalHandler SignalDeq SignalEnq SignalJam WaitForSignal VXI VME AcknowledgeVXIint Interrupt AssertVXIint DeAssertVXIint DefaultVXIintHandler DisableVXIint DisableVXItoSignalInt EnableVXIint EnableVXItoSignalInt GetVXIintHandler Appendix A Function Classification Reference National Instruments Corporation A 5 NI VXI User Manual Table A 1 Function Listing by Group Group Function VXI VME C C BASIC VXI VME RouteVXIint Interrupt SetVXIintHandler continued VXIintAcknowledgeMode Triggers AcknowledgeTrig DefaultTrigHandler DefaultTrigHandler2 DisableTrigSense EnableTrigSense GetTrigHandler MapTrigToTrig SetTrigHandler SrcTrig TrigAssertConfig TrigCntrConfig TrigExtConfig TrigTickConfig UnMapTrigToTrig WaitForTrig System Interrupt AssertSysreset Handler DefaultACfailHandler DefaultBusErrorHandler DefaultSoftResetHandler DefaultSysfailHandler DefaultSysresetHandler DisableACfail DisableSoftReset DisableSysfail Appendix A Function Classification Reference NI VXI User Manual A 6 National Instruments Corporation Table A 1 Function Listing by Group Group Function VXI VME C C BASIC System Interrupt DisableSysreset Handler En
19. WSgetTmo WSrd WSrdi WSrdl WSrdf WSresp WSLresp WSsetTmo WStrg WSwrt WSwrti WSwrtl WSwrtf Servant Word DefaultWSScmdHandler Serial Protocol DefaultWSSEcmdHandler DefaultWSSLcmdHandler DefaultWSSrdHandler DefaultWSSwrtHandler GenProtError GetWSScmdHandler GetWSSEcmdHandler GetWSSLcmdHandler GetWSSrdHandler GetWSSwrtHandler RespProtError SetWSScmdHandler SetWSSEcmdHandler SetWSSLcmdHandler SetWSSrdHandler Appendix A Function Classification Reference National Instruments Corporation A 3 NI VXI User Manual Table A 1 Function Listing by Group Group Function VXI VME C C BASIC Servant Word SetWSSwrtHandler Serial Protocol WSSabort continued WSSdisable WSSenable WSSnoResp WSSLnoResp WSSrd WSSrdi WSSrdl WSSsendResp WSSLsendResp WSSwrt WSSwrti WSSwrtl High Level VXIin VXI VMEbus VXIinReg Access VXImove VXIout VXIoutReg Low Level GetByteOrder VXI VMEbus GetContext Access GetPrivilege GetVXIbusStatus GetVXIbusStatusInd GetWindowRange MapVXIAddress MapVXIAddressSize SetByteOrder SetContext SetPrivilege UnMapVXIAddress VXIpeek VXIpoke Appendix A Function Classification Reference NI VXI User Manual A 4 National Instruments Corporation Table A 1 Function Listing by Group Group Function VXI VME C C BASIC Local Resource GetMyLa Access ReadMODID SetMODID
20. user code for processing statusID Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 19 NI VXI User Manual Note Although NI VXI simplifies the installation and use of callback handlers it cannot affect how the system handles interrupts The programmer must follow programming guidelines set by the chosen operating system Some of these guidelines could include using only reentrant functions adhering to timing restrictions and on Macintosh computers regaining access to global variables Triggers The addition of trigger lines to the VMEbus is one improvement the VXIbus has over VME in the field of instrumentation To take advantage of this feature NI VXI has a wide selection of functions you can use to set up your controller to both source and acknowledge trigger lines The TIC is a National Instruments ASIC Application Specific Integrated Circuit that gives you the capability to map trigger lines to trigger lines as well as to external lines use special counter timers and monitor multiple trigger lines simultaneously National Instruments Corporation 3 1 NI VXI User Manual Software Overview Chapter 3 This chapter describes the C C and BASIC usage of VXI and VME functions and briefly describes each function Functions are listed alphabetically in each functional group System Configuration Functions The VXI system configuration functions copy all of the Resource Manage
21. 3 25 VXIoutReg 3 25 I InitVXIlibrary function description 3 4 requirements for NI VXI programs 2 10 to 2 11 interrupt functions See system interrupt handler functions VXI interrupt functions interrupt handling C C example 2 18 overview 2 17 to 2 18 Index NI VXI User Manual I 4 National Instruments Corporation interrupts interrupt service routine support Commander Word Serial Protocol functions 3 7 to 3 8 interrupts and asynchronous events 1 4 to 1 5 L LabWindows CVI software 2 4 to 2 5 C C example 2 4 input versus output parameters 2 4 to 2 5 return values and system errors 2 4 to 2 5 type definitions 2 4 local resource access functions alphabetical list table A 4 GetMyLA 3 34 overview 2 2 3 34 ReadMODID 3 34 SetMODID 3 34 VXIinLR 3 35 VXImemAlloc 3 35 VXImemCopy 3 35 VXImemFree 3 35 VXIoutLR 3 36 Longword Serial Protocol 3 7 3 15 low level VXI VMEbus access functions alphabetical list table A 3 to A 4 GetByteOrder 3 30 GetContext 3 30 GetPrivilege 3 30 GetVXIbusStatus 3 30 GetVXIbusStatusInd 3 31 GetWindowRange 3 31 MapVXIAddress 3 28 3 29 3 31 MapVXIAddressSize 3 32 multiple pointer access for window 3 28 to 3 29 Access Only Privilege 3 28 to 3 29 Owner Privilege 3 28 overview 2 2 3 26 to 3 27 programming considerations 3 27 SetByteOrder 3 32 SetContext 3 32 SetPrivilege 3 33 UnMapVXIAddress 3 33 VXIpeek 3 28 3 33 VXIpoke 3 28 3 33
22. DisableSignalInt is called to inhibit more signals from being received Under the VXIbus specification if the local CPU signal FIFO becomes full in which case a signal be lost if another signal is written the local CPU must return a bus error on any subsequent writes to its Signal register This bus error condition notifies the sending CPU that the signal transfer needs to be retried This guarantees the application that even if the global signal queue becomes full no signals will be lost In addition to DisableSignalInt the DisableVXItoSignalInt function is also called to disable VXI VME interrupts from occurring on levels that are routed to the signal Processor When SignalDeq is called to remove a signal from the global signal queue the interrupts for the Signal register and the VXI VME interrupt levels routed to the signal handler are automatically re enabled If signals received never get dequeued the global signal queue eventually becomes full and the interrupts will be disabled forever If the signals were routed to the DefaultSignalHandler all except Unrecognized Command Events from message based devices perform no operation Unrecognized Command Events call the function WSabort to abort the current Word Serial operation in progress Chapter 3 Software Overview National Instruments Corporation 3 39 NI VXI User Manual Figure 3 3 provides a graphical overview of the NI VXI interrupt and signal functions RouteVXIint
23. In this configuration no input mapping is possible that is no trigger line can be mapped to the GPIO TrigTickConfig controller mode source tcount1 tcount2 TrigTickConfig configures the TIC chip s dual 5 bit tick timers This function can initialize with auto reload initialize with manual reload do a manual reload or disable the current tick timer settings If the tick timer is initialized you must call either EnableTrigSense or SrcTrig to start the tick timer You can use any GPIO line CLK10 or EXTCLK as the source of the tick timer Both tick timers TICK1 and TICK2 count independently from the same internal counter The range for each tick timer is specified as a power of two from 0 to 31 If you did not select auto reload the timer stops when TICK1 has counted to zero You can use MapTrigToTrig to map the TICK1 output signal to one or more trigger lines or to map the TICK2 output signal to one or more trigger lines or GPIO lines Both TICK1 and TICK2 outputs are square wave outputs The signal is asserted for the duration of the corresponding tick count and then unasserted for the duration of the count System Interrupt Handler Functions With these functions you can handle miscellaneous system conditions that can occur in the VXI VME environment such as Sysfail ACfail Sysreset Bus Error and or Soft Reset interrupts The NI VXI software interface can handle all of these system conditions for the application thro
24. M manual See documentation map trigger functions MapTrigToTrig 3 56 to 3 57 overview 3 56 UnMapTrigToTrig 3 57 MapECLtrig function 3 67 MapTrigToTrig function 3 56 to 3 57 MapTTLtrig function 3 67 to 3 68 MapUtilBus function 3 68 MapVXIAddress function description 3 31 MITE based platforms note 3 29 obtaining Access Only privilege 3 28 requesting owner privilege 3 28 MapVXIAddressSize function 3 32 MapVXIint function 3 68 master memory access C C example 2 14 to 2 15 functions versus macros note 2 16 overview 2 14 memory access See master memory access slave memory access message based devices 1 3 MITE based platforms note 3 29 multiple mainframe support 2 5 to 2 8 controllers 2 5 to 2 7 extender and controller parameters 2 7 to 2 8 Index National Instruments Corporation I 5 NI VXI User Manual multiple pointer access for window 3 28 to 3 29 Access Only Privilege 3 28 to 3 29 Owner Privilege 3 28 multitasking support Commander Word Serial Protocol functions cooperative 3 7 to 3 8 preemptive operating system 3 8 to 3 10 MXI 2 overview 1 5 to 1 6 MXIbus overview 1 5 N NI VXI Commander Servant hierarchies 1 4 interrupts and asynchronous events 1 4 to 1 5 message based devices 1 3 MXI 2 overview 1 5 to 1 6 MXIbus overview 1 5 register based devices 1 2 VXIbus overview 1 1 to 1 2 Word Serial Protocol 1 3 to 1 4 NI VXI driver software 2 9 to 2 19 beginning and end o
25. NI VXI User Manual July 1996 Edition Part Number 321228A 01 Copyright 1996 National Instruments Corporation All Rights Reserved Internet Support GPIB gpib support natinst com DAQ daq support natinst com VXI vxi support natinst com LabVIEW lv support natinst com LabWindows lw support natinst com HiQ hiq support natinst com VISA visa support natinst com Lookout lookout support natinst com E mail info natinst com FTP Site ftp natinst com Web Address http www natinst com Bulletin Board Support BBS United States 512 794 5422 or 800 327 3077 BBS United Kingdom 01635 551422 BBS France 1 48 65 15 59 FaxBack Support 512 418 1111 Telephone Support U S Tel 512 795 8248 Fax 512 794 5678 International Offices Australia 03 9 879 9422 Austria 0662 45 79 90 0 Belgium 02 757 00 20 Canada Ontario 519 622 9310 Canada Qu bec 514 694 8521 Denmark 45 76 26 00 Finland 90 527 2321 France 1 48 14 24 24 Germany 089 741 31 30 Hong Kong 2645 3186 Italy 02 413091 Japan 03 5472 2970 Korea 02 596 7456 Mexico 95 800 010 0793 Netherlands 0348 433466 Norway 32 84 84 00 Singapore 2265886 Spain 91 640 0085 Sweden 08 730 49 70 Switzerland 056 200 51 51 Taiwan 02 377 1200 U K 01635 523545 National Instruments Corporate Headquarters 6504 Bridge Point Parkway Austin TX 78730 5039 Tel 512 794 0100 Important Information Warranty The media on which you receive National Instruments
26. access privileges Because no other callers can succeed there is no problem with either destroying another caller s access state or having an inconsistent pointer environment Access Only Privilege A process can obtain Access Only Privilege by requesting access only privileges in the MapVXIAddress call With this privilege mode you Chapter 3 Software Overview National Instruments Corporation 3 29 NI VXI User Manual can have multiple pointers in the same process or over multiple processes to access a particular window simultaneously while still guaranteeing that the hardware context does not change between accesses The call succeeds under either of the following conditions No processes are mapped for the window first caller for Access Only Privilege for this window The hardware context is set as requested in the call The call returns a successful status and a valid C pointer and windowId for Access Only Privilege No process currently has Owner Privilege to the required window There are processes with Access Only Privilege but they are using the same hardware context privilege state byte order address range for their accesses to the window Because the hardware context is compatible it does not need to be changed The call returns a successful status and a valid C pointer and windowId for Access Only Privilege The successful call returns a valid pointer and a non negative return value The 32 bit windo
27. and Write Ready WR until asserted The modevalue parameter in the call specifies whether to send BAV only or BAV with END for the last byte of the transfer Chapter 3 Software Overview NI VXI User Manual 3 14 National Instruments Corporation WSwrtf la filename count modevalue retcount WSwrtf is an extension of the WSwrt function WSwrtf writes a specified number of bytes from the specified file to a message based Servant using the VXIbus Byte Transfer Protocol The process involves calling the WSwrt function possibly many times to write out a block of data read from the specified file The modevalue parameter in the call specifies whether to send BAV only or BAV with END for the last byte of the transfer Servant Word Serial Protocol Functions Word Serial communication is the minimal mode of communication between VXI message based devices within the VXI Commander Servant hierarchy The local CPU the CPU on which the NI VXI functions are running uses the Servant Word Serial functions to perform VXI message based Servant Word Serial communication with its Commander These functions are needed only in the case where the local CPU is not a top level Commander probably not the Resource Manager such as in a multiple CPU situation In a multiple CPU situation the local CPU must allow the Resource Manager device to configure the local CPU and can optionally implement some basic message transfer Word Serial communication wit
28. command query is sent Byte Available for WSwrt WSwrtf or Byte Request for WSrd WSrdf When the command transfer is complete the read or write call will continue exactly from where it was suspended No mutual exclusion is done between multiple command calls The application must guarantee that only one command call is pending at one time Read held off if write or trigger underway Write and trigger held off if read underway No mutual exclusion is done between multiple reads or multiple writes and triggers No more than one read call may be pending at any one time per logical address No more than one write or trigger call may be pending at any one time per logical address Figure 3 1 Preemptive Word Serial Mutual Exclusion Per Logical Address The Commander Word Serial functions are fully reentrant and preemptive on a per logical address basis Any number of logical addresses can have Commander Word Serial functions in progress without conflict Because Commander Word Serial is a protocol involving extensive polling support has been added for a round robin effect of Commander Word Serial function calls If a particular logical address does not respond within a set number of polls to a particular Word Serial command or query the process is suspended and another process possibly with a different Commander Word Serial call in progress can continue to execute The amount of time for which the process is suspended is dependent upo
29. corresponding enable and disable function is not possible Chapter 3 Software Overview National Instruments Corporation 3 65 NI VXI User Manual GetSoftResetHandler GetSoftResetHandler returns the address of the current Soft Reset interrupt handler A default handler DefaultSoftResetHandler is automatically installed when InitVXIlibrary initializes the NI VXI software Note The Soft Reset interrupt does not apply to VME GetSysfailHandler GetSysfailHandler returns the address of the current Sysfail interrupt handler A Sysfail condition detected on the local CPU generates an interrupt that calls the current Sysfail interrupt handler A default handler DefaultSysfailHandler is automatically installed when InitVXIlibrary initializes the NI VXI software GetSysresetHandler GetSysresetHandler returns the address of the current Sysreset interrupt handler The InitVXIlibrary function automatically installs a default handler DefaultSysresetHandler when it initializes the NI VXI software SetACfailHandler func SetACfailHandler replaces the current ACfail interrupt handler with an alternate handler An ACfail condition detected on the local CPU generates an interrupt that calls the current ACfail interrupt handler Your application can take any appropriate action within the allotted time period before complete power failure The InitVXIlibrary function automatically installs a default handler DefaultACfailHandl
30. embedded or extended controller s dependent on the hardware platform Notice that if the local CPU is configured to be reset by Sysreset conditions on the backplane the interrupt handler will not get invoked the CPU will reboot GetACfailHandler GetACfailHandler returns the address of the current ACfail interrupt handler An ACfail condition detected on the local CPU generates an interrupt that calls the current ACfail interrupt handler Your application can take any appropriate action within the allotted time period before complete power failure The InitVXIlibrary function automatically installs a default handler DefaultACfailHandler when it initializes the NI VXI software GetBusErrorHandler GetBusErrorHandler returns the address of the current bus error interrupt handler During an access to the VXI VMEbus the BERR signal bus error is asserted to end the bus cycle if the address or mode of access is determined to be invalid The bus error exception condition generates an exception on the local CPU which can be trapped by the bus error handler Your application should include a retry mechanism if it is possible for a particular access to generate bus errors at times and valid results at other times The InitVXIlibrary function automatically installs a default handler DefaultBusErrorHandler when it initializes the NI VXI software It increments the global variable BusErrorRecv Because bus errors can occur at any time a
31. external controller VXI MXI 1 3 53 triggers definition 3 51 overview 2 19 U UnMapTrigToTrig function 3 57 UnMapVXIAddress function 3 33 Unrecognized Command event interrupt service routine support 3 8 signal queuing 3 38 VXI interrupts 3 43 VXI signals 3 37 V VXI configuration registers figure 1 2 VXI devices 1 1 to 1 2 VXI interrupt functions AcknowledgeVXIint 3 46 to 3 47 alphabetical list table A 5 AssertVXIint 3 47 DeAssertVXIint 3 47 DefaultVXIntHandler 3 47 to 3 48 DisableVXIint 3 48 DisableVXItoSignalInt 3 38 3 48 EnableVXIint 3 48 to 3 49 EnableVXItoSignalInt 3 49 GetVXIintHandler 3 49 overview 2 2 3 43 to 3 44 programming considerations 3 45 ROAK versus RORA VXI VME interrupts 3 46 RouteVXIint 3 43 3 44 3 49 to 3 50 SetVXIintHandler 3 50 VXIintAcknowledgeMode 3 46 3 50 VXI only function groups 2 3 VXI signal functions alphabetical list table A 4 DefaultSignalHandler 3 40 DisableSignalInt 3 38 3 40 EnableSignalInt 3 40 GetSignalHandler 3 41 overview 2 2 3 36 to 3 37 programming considerations 3 38 to 3 39 RouteSignal 3 37 3 41 3 44 SetSignalHandler 3 41 SignalDeq 3 42 SignalEnq 3 42 SignalJam 3 42 WaitForSignal 3 37 3 39 to 3 40 3 42 3 44 VXI signal register 3 36 VXI signals definition 3 36 Event signals 3 37 Response signals 3 37 VXI trigger functions acceptor trigger functions AcknowledgeTrig 3 55 DefaultTrigHandler 3 55 DefaultTrigHand
32. into the address space the access privilege and the byte order for the accesses through the window Before accessing a particular address you must set up the window with the appropriate hardware context You can use the MapVXIAddress function for this purpose This function returns a pointer that you can use for subsequent accesses to the window with the VXIpeek and VXIpoke functions On most systems VXIpeek and VXIpoke are really C macros defines that dereference the pointer It is highly recommended to use these functions instead of performing the direct dereference within the application If your application does not use VXIpeek and VXIpoke it might not be portable between different platforms In addition VXIpeek and VXIpoke allow for compatibility between the C language and other languages such as BASIC Chapter 3 Software Overview NI VXI User Manual 3 28 National Instruments Corporation Multiple Pointer Access for a Window Application programmers can encounter a potential problem when the application requires different privilege states byte orders and or base addresses within the same window If the hardware context changes due to a subsequent call to MapVXIAddress or other calls such as SetPrivilege or SetByteOrder previously mapped pointers would not have their intended access parameters This problem is greater in a multitasking system where independent and conflicting processes can change the hardware context Two
33. sourcing TTL and ECL triggers as well as for detecting acknowledgments from accepting devices These functions can source any of the VXI defined trigger protocols from the local embedded controller or external extended controller s You can use the SrcTrig function to initiate any of the trigger protocols If the protocol requires an acknowledgment and your application is required to know when the acknowledgment occurs you must use the SetTrigHandler function to install a callback handler for the specified trigger line A default handler DefaultTrigHandler is installed for each one of the trigger lines when InitVXIlibrary is called You can use the SetTrigHandler function at any time to replace the default handlers SrcTrig controller line prot timeout Use SrcTrig to source any one of the VXI defined trigger protocols from the local CPU or from any remote frame extender device that supports trigger assertion For protocols that require an acknowledgment from the accepting device ASYNC or SEMI SYNC you need to specify whether to wait for an acknowledgment with a timeout or return immediately and let the trigger handler get called when the acknowledgment is received Another option is available in which you can assert or unassert any of the trigger lines continuously or have an external trigger possibly from the front panel routed to the VXIbus backplane Chapter 3 Software Overview NI VXI User Manual 3 58 National Instru
34. 2 20 mapping Establishing a range of address space for a one to one correspondence between each address in the window and an address in VXIbus memory master A functional part of a MXI VME VXIbus device that initiates data transfers on the backplane A transfer can be either a read or a write megabyte A million bytes Memory Class device A VXIbus device that in addition to configuration registers has memory in VME A24 or A32 space that is accessible through addresses on the VME VXI data transfer bus message based device An intelligent device that implements the defined VXIbus registers and communication protocols These devices are able to use Word Serial Protocol to communicate with one another through communication registers MODID A set of 13 signal lines on the VXI backplane that VXI systems use to identify which modules are located in which slots in the mainframe MQE Multiple Query Error a type of Word Serial Protocol error If a Commander sends two Word Serial queries to a Servant without reading the response to the first query before sending the second query a MQE is generated multitasking The ability of a computer to perform two or more functions simultaneously without interference from one another In operating system terms it is the ability of the operating system to execute multiple applications processes by time sharing the available CPU resources MXIbus Multisystem eXtension Interface Bus a high per
35. CloseVXIlibrary is the application termination routine which must be included at the end or abort of any application CloseVXIlibrary disables interrupts and frees dynamic memory allocated for the internal RM table and other structures You must include a call to CloseVXIlibrary at the termination of your application for whatever reason to free all data structures allocated by InitVXIlibrary and disable interrupts Failure to call CloseVXIlibrary when terminating your application can cause unpredictable and undesirable results If your application can be aborted from some operating system abort routine such as a break key or a process kill signal be certain to install an abort close routine to call CloseVXIlibrary CreateDevInfo la CreateDevInfo creates a new entry in the dynamic NI VXI RM table for the specified logical address It installs default NULL values into the entry You must use one of the SetDevInfo functions after this point to change any of the device information as needed This operation is not needed for VME devices since it is recommended that you use the Non VXI Device Editor in the VXIedit or VXItedit NI VXI resource editor utility At the startup of your application InitVXIlibrary completely initializes the RM table to how the RM configured the VXI system No initial changes creations are necessary for VXI devices You can use CreateDevInfo to add non VXI devices or pseudo devices future expansion FindDevLA nam
36. Commander ret Return value RM See Resource Manager Glossary NI VXI User Manual G 12 National Instruments Corporation ROAK Release On Acknowledge a type of VXI interrupter which always deasserts its interrupt line in response to an IACK cycle on the VXIbus All message based VXI interrupters must be ROAK interrupters ROR Release On Request a type of VME bus arbitration where the current VMEbus master relinquishes control of the bus only when another bus master requests the VMEbus RORA Release On Register Access a type of VXI VME interrupter which does not deassert its interrupt line in response to an IACK cycle on the VXIbus A device specific register access is required to remove the interrupt condition from the VXIbus The VXI specification recommends that VXI interrupters be only ROAK interrupters RR Read Ready a bit in the Response register of a message based device used in Word Serial Protocol indicating that a response to a previously sent query is pending RRviol Read Ready protocol violation a type of Word Serial Protocol error If a Commander attempts to read a response from the Data Low register when the device is not Read Ready does not have a response pending a Read Ready violation may be generated rsv Request Service a bit in the status byte of an IEEE 488 1 and 488 2 device indicating a need for service In VXI whenever a new need for service arises the rsv bit should be set and the REQT
37. NI VXI Functions NI VXI User Manual 2 14 National Instruments Corporation Master Memory Access You can access VXIbus memory directly through the NI VXI high level and low level VXIbus access functions within the capabilities of the controller The main difference between the high level and low level access functions is in the amount of encapsulation given by NI VXI The high level VXIbus access functions include functions such as VXIin and VXImove that you can use to access memory in the VXI system without dealing with such details as memory mapping windows status checking and recovering from bus timeouts Although these functions tend to have more overhead associated with them than the low level functions they are much simpler to use and typically require less debugging We recommend that beginner programmers in VXI rely on the high level functions until they are familiar with VXI memory accesses You can use the low level VXI VMEbus access functions if you want to access VXI VME memory with as little overhead as possible Although you now have to perform such actions as bus error handling and mapping which are handled automatically by the high level functions you can experience a performance gain if you optimize for the particular accesses you are performing Consider the following sample code which performs a memory access using the low level functions Notice that there is no bus error handler installed by the program
38. NI VXI User Manual Glossary Prefix Meaning Value n nano 10 9 m milli 10 3 K kilo 103 M mega 106 G giga 109 A A16 space One of the VXIbus address spaces Equivalent to the VME 64 KB short address space In VXI the upper 16 KB of A16 space is allocated for use by VXI devices configuration registers This 16 KB region is referred to as VXI configuration space A24 space One of the VXIbus address spaces Equivalent to the VME 16 MB standard address space A32 space One of the VXIbus address spaces Equivalent to the VME 4 GB extended address space ACFAIL A VMEbus backplane signal that is asserted when a power failure has occurred either AC line source or power supply malfunction or if it is necessary to disable the power supply such as for a high temperature condition address Character code that identifies a specific location or series of locations in memory Glossary NI VXI User Manual G 2 National Instruments Corporation address modifier One of six signals in the VMEbus specification used by VMEbus masters to indicate the address space and mode supervisory nonprivileged data program block in which a data transfer is to take place address space A set of 2n memory locations differentiated from other such sets in VXI VMEbus systems by six signal lines known as address modifiers n is the number of address lines required to uniquely specify a byte location in a given
39. See the Interrupts and Signals section Instead the program uses the NI VXI default bus error handler This handler automatically increments the BusErrorRecv global variable C C Example include lt nivxi h gt BusErrorRecv defined in nivxi h include lt stdio h gt main INT16 ret la UINT16 addrptr svalue UINT32 addr window1 INT32 timeout UINT32 addrptr1 Start all programs with this function ret InitVXIlibrary BusErrorRecv 0 Reset global variable The following code maps the A16 space with the Access Only access in order to access the A16 space directly addr 0xc000L Map upper 16 KB of the A16 space Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 15 NI VXI User Manual timeout 2000L 2 seconds Notice the use of the macros for defining the access parameters These can be found in the NI VXI header files addrptr1 UINT32 MapVXIAddress AccessP_Space A16_SPACE AccessP_Priv NonPriv_DATA AccessP_BO MOTOROLA_ORDER AccessP_Owner 0 addr timeout amp window1 amp ret if ret gt 0 MapVXIAddress call is successful The following code reads the ID register of a device at logical address 10 la 10 addrptr UINT16 UINT32 addrptr1 64 la VXIpeek addrptr 2 amp svalue if BusErrorRecv printf Bus Error has occurred n else printf Value read was
40. This Manual Organization of This Manual xiii Conventions Used in This Manual xiv Related Documentation xv Customer Communication xv Chapter 1 Overview of NI VXI VXIbus Overview 1 1 VXI Devices 1 1 Register Based Devices 1 2 Message Based Devices 1 3 Word Serial Protocol 1 3 Commander Servant Hierarchies 1 4 Interrupts and Asynchronous Events 1 4 MXIbus Overview 1 5 MXI 2 Overview
41. acknowledge the specified interrupt AssertVXIint controller level statusId AssertVXIint asserts a particular VXI VME interrupt level on a specified controller embedded or extended and returns the specified status ID value when acknowledged You can use AssertVXIint to send any status ID value to the VXI VME interrupt handler configured for the specified VXI VME interrupt level AssertVXIint returns immediately that is it does not wait for the interrupt to be acknowledged You can call GetVXIbusStatus to detect if the interrupt has been serviced Use DeAssertVXIint to unassert a interrupt that had been asserted using AssertVXIint but has not yet been acknowledged DeAssertVXIint controller level DeAssertVXIint unasserts the VXI VME interrupt level on a given controller that was previously asserted using the AssertVXIint function You can use AssertVXIint to send any status ID value to the VXI VME interrupt handler configured for the specified interrupt level You can call GetVXIbusStatus to detect if the interrupt has been serviced Use DeAssertVXIint to unassert a VXI VME interrupt that had been asserted using AssertVXIint but has not yet been acknowledged Note Unasserting an interrupt may violate the VME and VXIbus specifications if the interrupt has not yet been acknowledged by the interrupt handler DefaultVXIintHandler controller level statusId DefaultVXIintHandler is the sample handler for VXI VME interrupts wh
42. be handled as a RORA interrupt the local CPU automatically inhibits VXI VME interrupt generation for the corresponding controller and levels whenever the corresponding VXI VME interrupt occurs After the application has handled and caused the RORA interrupter to unassert the interrupt line either EnableVXIint or EnableVXItoSignalInt must be called to re enable local CPU interrupt generation The following paragraphs describe the VXI VME interrupt functions and default handler The descriptions are presented at a functional level describing the operation of each of the functions The functions are grouped by area of functionality AcknowledgeVXIint controller level statusId AcknowledgeVXIint performs a VXI VME interrupt acknowledge IACK cycle on the backplane in the specified controller and VXI VME interrupt level Note This function is intended only for debugging purposes Chapter 3 Software Overview National Instruments Corporation 3 47 NI VXI User Manual Normally VXI VME interrupts are automatically acknowledged when enabled via the function EnableVXIint However if the interrupts are not enabled and the assertion of an interrupt is detected through some method such as GetVXIbusStatus you can use AcknowledgeVXIint to acknowledge an interrupt and return the status ID value If the controller parameter specifies an extended controller AcknowledgeVXIint specifies hardware on the VXI VME frame extender if present to
43. byte in the buffer written A buffer read is a series of Byte Request Word Serial queries sent to the Servant with the additional constraint that the Data Out Ready DOR bit as well as the WR bit must be asserted before sending the Byte Request The lower 8 bits bits 0 to 7 of the 16 bit response contain a single byte of data bit 8 is the END bit Therefore one Byte Request is sent for each data byte in the buffer read In addition to polling the WR RR DIR and DOR bits during various Word Serial transfers the functions also check the ERR bit The ERR bit indicates when a Word Serial Protocol error occurs The Word Serial Protocol errors are Unsupported Command Multiple Query Error MQE DIR Violation DOR Violation RR Violation or WR Violation The Servant Word Serial Protocol functions let the local CPU generate any of the Word Serial Protocol errors and respond to the Read Protocol Error Word Serial query with the corresponding protocol error The functions automatically handle asserting and deasserting of the ERR bit The Longword Serial and Extended Longword Serial Protocols are similar to the Word Serial Protocol but involve 32 bit and 48 bit command transfers respectively instead of the 16 bit transfers of the Word Serial Protocol The VXI specification however provides no common command usages for these protocols The commands are either VXI Reserved or User Defined The NI VXI interface gives you the ability to re
44. cable connected towards the root frame in the frame acts as a remote controller An embedded or external controller may use a remote controller to control the remote mainframe External controller A desktop computer or workstation connected to the VXI VME system via a MXI interface board An example is a standard personal computer with a PCI MXI 2 installed In general a multiple mainframe VXI VME system will have one of the following controller configurations An embedded controller in one frame that is connected to other frames via mainframe extenders using MXI 2 VXI MXI 2 or VME MXI 2 boards in the other frames can also be used as remote controllers See Figure 2 1 bus NATIONAL INSTRUMENTS NATIONAL INSTRUMENTS bus Embedded Controller Extender and Remote Controller Extender Only bus NATIONAL INSTRUMENTS Figure 2 1 An Embedded Controller Connected to Other Frames via Mainframe Extenders Using MXI 2 An external controller connected using MXI 2 to a number of remote controllers each in a separate frame The external controller can use the remote controllers for control of the VXI VME system or it can use its own controller capabilities See Figure 2 2 Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 7 NI VXI User Manual bus NATIONAL INSTRUMENTS bus NATIONAL INSTRUMENTS bus NATIONAL INSTRUMENTS NATIONAL INSTRUMENTS
45. console responses variable names and syntax examples In this manual numbers are decimal unless noted as follows Binary numbers are indicated by a b suffix for example 11010101b Octal numbers are indicated by an o suffix for example 325o Hexadecimal numbers are indicated by an h suffix for example D5h ASCII character and string values are indicated by double quotation marks for example This is a string Long values are indicated by an L suffix for example 0x1111L Abbreviations acronyms metric prefixes mnemonics symbols and terms are listed in the Glossary About This Manual National Instruments Corporation xv NI VXI User Manual Related Documentation The following documents contain information that you may find helpful as you read this manual IEEE Standard for a Versatile Backplane Bus VMEbus ANSI IEEE Standard 1014 1987 Multisystem Extension Interface Bus Specification Version 2 0 VXI 1 VXIbus System Specification Revision 1 4 VXIbus Consortium VXI 6 VXIbus Mainframe Extender Specification Revision 1 0 VXIbus Consortium Customer Communication National Instruments wants to receive your comments on our products and manuals We are interested in the applications you develop with our products and we want to help if you have problems with them To make it easy for you to contact us this manual contains comment and configura
46. devices a set of registers that are accessible to the registers device s Commander and are used for performing Word Serial Protocol communications configuration registers A set of registers through which the system can identify a module device type model manufacturer address space and memory requirements In order to support automatic system and memory configuration the VXIbus specification requires that all VXIbus devices have a set of such registers controller A device that is capable of controlling other devices A desktop computer with a MXI interface board an embedded computer in a VXI chassis a VXI MXI and a VME MXI may all be controllers depending on the configuration of the VXI system CR Carriage Return the ASCII character 0Dh Glossary National Instruments Corporation G 5 NI VXI User Manual D Data Transfer Bus One of four buses on the VMEbus backplane The DTB is used by a bus master to transfer binary data between itself and a slave device decimal Numbering system based upon the 10 digits 0 to 9 Also known as base 10 de referencing Accessing the contents of the address location pointed to by a pointer default handler Automatically installed at startup to handle associated interrupt conditions the software can then replace it with a specified handler DIR Data In Ready This is a bit in the Response register of a message based device that indicates that the device is ready to accept dat
47. for the ACfail interrupt and is installed as a default handler when InitVXIlibrary initializes the NI VXI software It increments the global variable ACfailRecv The VXI VMEbus specification allows for a minimum amount of time after a power failure condition occurs for the system to remain operational The detection of a power failure in a VXI VME system asserts the backplane signal ACFAIL An ACfail condition detected on the local CPU generates an interrupt that calls the current ACfail interrupt handler Your application can take any appropriate action within the allotted time period before complete power failure Your application must then call EnableACfail to enable ACfail interrupts after the InitVXIlibrary call DefaultBusErrorHandler DefaultBusErrorHandler is the sample handler for the bus error exception and is installed as a default handler when InitVXIlibrary initializes the NI VXI software During an access to the VXI VMEbus the BERR signal bus error is asserted to end the bus cycle if the address or mode of access is determined to be invalid The bus error exception condition generates an exception on the local CPU which can be trapped by the bus error handler Your application should include a retry mechanism if it is possible for a particular access to generate bus errors at times and valid results at other times Because bus errors can occur at any time a corresponding enable and disable function is not possible Notice t
48. functions will vary when called from different processes depending on how your operating system performs multitasking Interrupt Service Routine Support If portability between operating systems is essential the Word Serial Protocol functions should not be called from an interrupt service routine Only for operating systems in which the user installed handlers are run at process level most UNIX OS 2 and Windows 95 NT systems is it possible to initiate Word Serial operations from a user installed handler The Commander Word Serial functions require operating system support provided only at the application process level of execution Calling these functions from the CPU interrupt level will have undetermined results Chapter 3 Software Overview NI VXI User Manual 3 8 National Instruments Corporation The WSabort function is the only exception to this restriction WSabort is used to abort various Word Serial transfers in progress and will usually be called from an interrupt service routine although it is not limited to interrupt service routines The most common example of calling this function from an interrupt service routine is with the handling of Unrecognized Command events from a device When an Unrecognized Command event is received by the NI VXI interrupt or Signal interrupt handler WSabort must be called to abort the current Word Serial command transfer in progress that caused the generation of the Unrecognized Command eve
49. hd n svalue ret UnMapVXIAddress window1 else printf Unable to access window n Close library when done ret CloseVXIlibrary Notice that the return variable for the MapVXIAddress function is a pointer While you can dereference this pointer directly on some platforms we recommend that you use the VXIpeek and VXIpoke macros and functions in NI VXI instead You can define BINARY_COMPATIBLE when compiling your program to force NI VXI to use a version of VXIpeek and VXIpoke macros that will work on all embedded and MXI platforms In addition you can use the functions rather than the macros to ensure future compatibility To force the compiler to use the functions put the function name in parentheses for example VXIpoke addrptr 2 0 instead of VXIpoke addrptr 2 0 Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 16 National Instruments Corporation Note On modern 32 bit operating systems running on high performance processors such as Microsoft Windows NT on a Pentium or Solaris 2 on a SPARC we have found no performance gained by using macros instead of functions For this reason we strongly recommend that you use functions on these platforms to allow your program to be more portable across future platforms Slave Memory Access It is possible to share local resources such as RAM with the VXI VMEbus You can accomplish this functionality by setti
50. mainframe extenders and configures a single or multiple mainframe VXI VME system Refer to the VXIbus Mainframe Extender Specification Revision 1 3 or later for more details on multiple mainframe systems If you have a multiple mainframe VXI VME system please continue with the following sections If you have a single mainframe system you can skip to the Using NI VXI section later in this chapter Controllers A controller is a device that is capable of controlling other devices A desktop computer with a MXI interface board an embedded computer in a VXI VME chassis a VXI MXI and a VME MXI may all be controllers depending on the configuration of the system There are several types of controllers that may exist in a VXI VME system embedded external and remote Embedded controller A computer plugged directly into the VXI VME backplane An example is the National Instruments VXIpc 850 All of the required VXI VME interface capabilities are built directly onto the computer itself An embedded computer has direct access to the VXI VMEbus backplane in which it is installed Remote controller A device in the VXI VME system that has the capability to control the VXI VMEbus but has no intelligent CPU installed An example is the VXI MXI 2 In NI VXI the parent side VXI MXI 2 that is the VXI MXI 2 with a MXI 2 Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 6 National Instruments Corporation
51. mapping based on user modifiable configuration files The MapVXIint function can dynamically reconfigure the utility bus mapping Only special circumstances should require any changes to the default configuration National Instruments Corporation1 A 1 NI VXI User Manual Function Classification Reference A Appendix This appendix contains two tables you can use as a quick reference Table A 1 Function Listing by Group lists the NI VXI functions by their group association This arrangement can help you determine easily which functions are available within each group Table A 2 Function Listing by Name lists each function alphabetically You can refer to this table if you don t remember the group association of a particular function Both tables use checkmarks to denote whether a VXI function also applies to VME and also whether it is associated with C C and or BASIC Table A 1 Function Listing by Group Group Function VXI VME C C BASIC System CloseVXIlibrary Configuration CreateDevInfo FindDevLA GetDevInfo GetDevInfoLong GetDevInfoShort GetDevInfoStr InitVXIlibrary SetDevInfo SetDevInfoLong SetDevInfoShort SetDevInfoStr Appendix A Function Classification Reference NI VXI User Manual A 2 National Instruments Corporation Table A 1 Function Listing by Group Group Function VXI VME C C BASIC Commander WSabort Word Serial WSclr Protocol WScmd WSEcmd WSLcmd
52. must check error conditions such as Bus Error BERR separately Chapter 3 Software Overview National Instruments Corporation 3 27 NI VXI User Manual Programming Considerations All accesses to the VXI VMEbus address spaces are performed by reads and writes to particular offsets within the local CPU address space which are made to correspond to addresses on the VXI VMEbus using a hardware interface The areas where the address space of the local CPU is mapped onto the VXI VMEbus are referred to as windows The sizes and numbers of windows present vary depending on the hardware being used The size of the window is always a power of two where a multiple of the size of the window would encompass an entire VXI VMEbus address space The multiple for which a window currently can access is determined by modifying a window base register The constraints of a particular hardware platform lead to restrictions on the area of address space reserved for windows into VXI VMEbus address spaces Be sure to take into account the number and size of the windows provided by a particular platform If a mapped pointer is to be incremented or decremented the bounds for accessing within a particular address space must be tested before accessing within the space NI VXI uses a term within this chapter called the hardware or window context The hardware context for window to VXI VME consists of the VXI VME address space being accessed the base offset
53. mutual exclusion necessary for a multitasking environment Each individual platform has been optimized within the boundaries of the particular hardware and operating system environment Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 4 National Instruments Corporation LabWindows CVI You can use the functions described in this manual with LabWindows CVI LabWindows CVI is an integrated development environment for building instrumentation applications using the ANSI C programming language You can use LabWindows CVI with Microsoft Windows on PC compatible computers or with Solaris on Sun SPARCstations The source code you develop is portable across either platform National Instruments offers VXI VME development systems for these two platforms that link the NI VXI driver software into LabWindows CVI to control VXI instruments from either embedded VXI VME controllers or external computers equipped with a MXI interface All of the NI VXI functions described in this manual are completely compatible with LabWindows CVI Type Definitions The following data types are used for all parameters in the NI VXI functions and in the actual NI VXI library function definitions NI VXI uses this list of parameter types as an independent method for specifying data type sizes among the various operating systems and target CPUs of the NI VXI software interface C C Example typedef char INT8 8 bit signed integer t
54. number of signals on a standard MXI cable by including VXI triggers all VXI VME interrupts CLK10 and all of the utility bus signals SYSFAIL SYSRESET and ACFAIL Chapter 1 Overview of NI VXI NI VXI User Manual 1 6 National Instruments Corporation Because MXI 2 incorporates all of these new signals into a single connector the triggers interrupts and utility signals can be extended not only to other mainframes but also to the local CPU in all MXI 2 products using a single cable Thus MXI 2 lets CPU interface boards such as the PCI MXI 2 perform as though they were plugged directly into the VXI VME backplane In addition MXI 2 boosts data throughput performance past previous generation MXIbus products by defining new high performance protocols MXI 2 is a superset of MXI However MXI 2 defines synchronous MXI block data transfers which surpass previous block data throughput benchmarks The new synchronous MXI block protocol increases MXI 2 throughput to a maximum of 33 MB s between two MXI 2 devices All National Instruments MXI 2 boards are capable of initiating and responding to synchronous MXI block cycles National Instruments Corporation 2 1 NI VXI User Manual Introduction to the NI VXI Functions Chapter 2 This chapter introduces you to the NI VXI functions and their capabilities Additional discussion is provided for each function s parameters and includes descriptions of the application development e
55. of cmd It then polls the RR bit before reading the 32 bit response from the Data Low and Data High registers there are no 48 bit responses for Extended Longword Serial WSEcmd polls the WR bit after either sending the command for a command or reading the response for a query to guarantee that no protocol errors occurred during the transfer WSgetTmo actualtimo WSgetTmo retrieves the current timeout period for all of the Commander Word Serial Protocol functions It retrieves the current timeout value in milliseconds to the nearest resolution of the host CPU WSLcmd la cmd respflag response WSLcmd sends a Longword Serial command or query to a message based Servant It polls the WR bit before sending the command WSLcmd sends the command by writing the Data High register first with the upper 16 bits of the 32 bit command and then writing the Data Low register with the lower 16 bits of the 32 bit command It then polls the RR bit before reading the 32 bit response from the Data Low and Data High registers WSLcmd polls the WR bit after either sending the command for a command or reading the response for a query to guarantee that no protocol errors occurred during the transfer WSLresp la response WSLresp retrieves a response to a previously sent Longword Serial Protocol query from a VXI message based Servant Note This function is intended only for debugging purposes Chapter 3 Software Overview NI VXI User
56. the size passed to MapVXIAddressSize MapVXIAddressSize only provides a preferred size to the MapVXIAddress If it is not possible to map a window to the given size MapVXIAddress can use a different size To determine the exact size of window mapped use the GetWindowRange function Note Not all platforms support MapVXIAddressSize SetByteOrder window ordermode SetByteOrder sets the byte word order of data transferred into or out of the specified window The two possible settings are Motorola most significant byte word first or Intel least significant byte word first The application must have Owner Access Privilege to the applicable window for this function to execute successfully Notice that some hardware platforms do not allow you to change the byte order of a window which is reflected in the return code of the call to SetByteOrder Most Intel processor based hardware platforms support both byte order modes Most Motorola processor based hardware platforms support only the Motorola byte order mode because the VXI VMEbus is based on Motorola byte order SetContext window context SetContext sets all of the hardware interface settings context for a particular VXI VME window The application must have Owner Access Privilege to the applicable window for this function to execute successfully Any application can use GetContext along with SetContext to save and restore the VXI VME interface hardware state context for a partic
57. time an Extended Longword Serial command is received GetWSSLcmdHandler GetWSSLcmdHandler returns the address of the current WSSLcmd interrupt handler function While Word Serial operations are enabled the WSSLcmd interrupt handler is called whenever a Longword Serial command is received GetWSSrdHandler GetWSSrdHandler returns the address of the current WSSrd interrupt handler function When WSSrd reaches the specified count or an END bit or an error occurs it calls the WSSrd interrupt handler with the status of the call GetWSSwrtHandler GetWSSwrtHandler returns the address of the current WSSwrt interrupt handler function When WSSwrt reaches the specified count or an error occurs it calls the WSSwrt interrupt handler with the status of the call RespProtError When the Word Serial Read Protocol Error query is received RespProtError places the saved error response in the Data Low register sets the saved error response to ffffh no error unasserts ERR and sets RR If no previous error is pending the value ffffh no error is returned SetWSScmdHandler func SetWSScmdHandler replaces the current WSScmd interrupt handler with an alternate handler While Word Serial operations are enabled the WSScmd interrupt handler is called whenever a Word Serial command is received other than BAV if a WSSrd call is pending or BREQ if a WSSwrt call is pending A default handler DefaultWSScmdHandler is supplied in
58. to the VME standard Tight timing and signaling is important between many types of controllers and or instruments In the past clumsy cables of specified length had to be connected between controllers and or instruments to get the required timing For many systems phase shifting and propagation delays had to be calculated precisely based on the instrument connection scheme This limited the architecture of many systems In VXI however every VXI board with a P2 connector has access to eight 10 MHz TTL trigger lines If the VXI board has a P3 connector it has access to six 100 MHz ECL trigger lines The phase shifting and propagation delays can be held to a known maximum based on the VXIbus specification s rigid requirement on backplanes The VXIbus specification does not currently prescribe an allocation method for TTL or ECL trigger lines The application must decide how to allocate required trigger lines The VXIbus specification specifies several trigger protocols that can be supported thereby promoting compatibility among the various VXI devices The following is a description of the four basic protocols SYNC SYNC protocol is the most basic protocol SYNC protocol is a pulse of a minimum time 30 ns on TTL 8 ns on ECL on any one of the trigger lines ASYNC ASYNC is a two device two line handshake protocol ASYNC uses two consecutive even odd trigger lines a source acceptor line and an acknowledge line respective
59. 1 Overview of NI VXI NI VXI User Manual 1 4 National Instruments Corporation a fashion very similar to IEEE 488 instruments In general message based devices typically contain some level of local intelligence that uses or requires a high level of communication In addition the Word Serial Protocol has messages for configuring message based devices and system resources All VXI message based devices are required to use the Word Serial Protocol and communicate in a standard way The protocol is called word serial because if you want to communicate with a message based device you do so by writing and reading 16 bit words one at a time to and from the Data In write Data Low and Data Out read Data Low hardware registers located on the device itself Word serial communication is paced by bits in the device s response register that indicate whether the Data In register is empty and whether the Data Out register is full This operation is very similar to the operation of a Universal Asynchronous Receiver Transmitter UART on a serial port Commander Servant Hierarchies The VXIbus specification defines a Commander Servant communication protocol you can use to construct hierarchical systems using conceptual layers of VXI devices The resulting structure is like a tree A Commander is any device in the hierarchy with one or more associated lower level devices or Servants A Servant is any device in the subtree of a Commander A device ca
60. 10 to 2 11 3 2 CreateDevInfo 3 2 FindDevLA 3 2 GetDevInfo 3 3 GetDevInfoLong 3 3 GetDevInfoShort 3 3 GetDevInfoStr 3 3 InitVXIlibrary 3 4 obtaining system information 2 11 to 2 12 C C example 2 12 overview 2 1 3 1 SetDevInfo 3 4 SetDevInfoLong 3 4 SetDevInfoShort 3 5 SetDevInfoStr 3 5 system interrupt handler functions alphabetical list table A 6 AssertSysreset 3 60 DefaultACfailHandler 3 60 DefaultBusErrorHandler 3 60 to 3 61 DefaultSoftResetHandler 3 61 DefaultSysfailHandler 3 61 to 3 63 DisableSysreset 3 63 EnableACfail 3 63 EnableSoftReset 3 63 EnableSysfail 3 63 to 3 64 EnableSysreset 3 64 GetACfailHandler 3 64 GetBusErrorHandler 3 64 GetSoftResetHandler 3 65 GetSysfailHandler 3 65 GetSysresetHandler 3 65 overview 2 2 3 59 to 3 60 SetACfailHandler 3 65 SetBusErrorHandler 3 65 to 3 66 SetSoftResetHandler 3 66 SetSysfailHandler 3 66 SetSysresetHandler 3 66 T technical support B 1 to B 2 trigger configuration functions overview 3 58 TrigAssertConfig 3 58 TrigCntrConfig 3 58 TrigExtConfig 3 58 to 3 59 TrigTickConfig 3 59 trigger functions See VXI trigger functions trigger lines ECL 3 51 TTL 3 51 trigger protocols ASYNC 3 51 ON OFF 3 52 SEMI SYNC 3 51 to 3 52 Index NI VXI User Manual I 8 National Instruments Corporation START STOP 3 52 SYNC 3 51 triggering hardware capabilities 3 52 to 3 54 embedded external MXI 2 and remote controller 3 54
61. 879 9422 03 9 879 9179 Austria 0662 45 79 90 0 0662 45 79 90 19 Belgium 02 757 00 20 02 757 03 11 Canada Ontario 519 622 9310 Canada Quebec 514 694 8521 514 694 4399 Denmark 45 76 26 00 45 76 26 02 Finland 90 527 2321 90 502 2930 France 1 48 14 24 24 1 48 14 24 14 Germany 089 741 31 30 089 714 60 35 Hong Kong 2645 3186 2686 8505 Italy 02 413091 02 41309215 Japan 03 5472 2970 03 5472 2977 Korea 02 596 7456 02 596 7455 Mexico 95 800 010 0793 5 520 3282 Netherlands 0348 433466 0348 430673 Norway 32 84 84 00 32 84 86 00 Singapore 2265886 2265887 Spain 91 640 0085 91 640 0533 Sweden 08 730 49 70 08 730 43 70 Switzerland 056 200 51 51 056 200 51 55 Taiwan 02 377 1200 02 737 4644 U K 01635 523545 01635 523154 Technical Support Form Photocopy this form and update it each time you make changes to your software or hardware and use the completed copy of this form as a reference for your current configuration Completing this form accurately before contacting National Instruments for technical support helps our applications engineers answer your questions more efficiently If you are using any National Instruments hardware or software products related to this problem include the configuration forms from their user manuals Include additional pages if necessary Name __________________________________________________________________________ Title _______________________________________________________
62. 9 600 baud 8 data bits 1 stop bit no parity France 1 48 65 15 59 Up to 9 600 baud 8 data bits 1 stop bit no parity FTP Support To access our FTP site log on to our Internet host ftp natinst com as anonymous and use your Internet address such as joesmith anywhere com as your password The support files and documents are located in the support directories FaxBack Support FaxBack is a 24 hour information retrieval system containing a library of documents on a wide range of technical information You can access FaxBack from a touch tone telephone at 512 418 1111 E Mail Support currently U S only You can submit technical support questions to the appropriate applications engineering team through e mail at the Internet addresses listed below Remember to include your name address and phone number so we can contact you with solutions and suggestions GPIB gpib support natinst com LabVIEW lv support natinst com DAQ daq support natinst com HiQ hiq support natinst com VXI vxi support natinst com VISA visa support natinst com LabWindows lw support natinst com Lookout lookout support natinst com Telephone and Fax Support National Instruments has branch offices all over the world Use the list below to find the technical support number for your country If there is no National Instruments office in your country contact the source from which you purchased your software to obtain support Telephone Fax Australia 03 9
63. CIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE CUSTOMER S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF NATIONAL INSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTOMER NATIONAL INSTRUMENTS WILL NOT BE LIABLE FOR DAMAGES RESULTING FROM LOSS OF DATA PROFITS USE OF PRODUCTS OR INCIDENTAL OR CONSEQUENTIAL DAMAGES EVEN IF ADVISED OF THE POSSIBILITY THEREOF This limitation of the liability of National Instruments will apply regardless of the form of action whether in contract or tort including negligence Any action against National Instruments must be brought within one year after the cause of action accrues National Instruments shall not be liable for any delay in performance due to causes beyond its reasonable control The warranty provided herein does not cover damages defects malfunctions or service failures caused by owner s failure to follow the National Instruments installation operation or maintenance instructions owner s modification of the product owner s abuse misuse or negligent acts and power failure or surges fire flood accident actions of third parties or other events outside reasonable control Copyright Under the copyright laws this publication may not be reproduced or transmitted in any form electronic or mechanical including photocopying recording storing in an information retrieval system or translating in whole or in
64. ME C C BASIC Access VXIinReg High Level VXI VMEbus Access VXIintAcknowledgeMode VXI VME Interrupt VXImemAlloc Local Resource Access VXImemCopy Local Resource Access VXImemFree Local Resource Access VXImove High Level VXI VMEbus Access VXIout High Level VXI VMEbus Access VXIoutLR Local Resource Access VXIoutReg High Level VXI VMEbus Access VXIpeek Low Level VXI VMEbus Access VXIpoke Low Level VXI VMEbus Access WaitForSignal VXI Signal WaitForTrig Triggers WSabort Commander Word Serial Protocol WSclr Commander Word Serial Protocol WScmd WSEcmd WSLcmd Commander Word Serial Protocol WSgetTmo Commander Word Serial Protocol WSresp WSLresp Commander Word Serial Protocol WSrd WSrdi WSrdl Commander Word Serial Protocol Appendix A Function Classification Reference National Instruments Corporation A 13 NI VXI User Manual Table A 2 Function Listing by Name Function Group VXI VME C C BASIC WSrdf Commander Word Serial Protocol WSSabort Servant Word Serial Protocol WSSdisable Servant Word Serial Protocol WSSenable Servant Word Serial Protocol WSsetTmo Word Serial Protocol WSSnoResp WSSLnoResp Servant Word Serial Protocol WSSrd WSSrdi WSSrdl Servant Word Serial Protocol WSSsendResp WSSLsendResp Servant Word Serial Protocol WSSwrt WSSwrti WSSwrtl Servant Word Serial Protocol WStrg Commander Word Serial Pro
65. MXIbus daisy chain system hierarchy The tree structure of the Commander Servant relationships of all devices in the system at a given time In the VXIbus structure each Servant has a Commander A Commander can in turn be a Servant to another Commander T TIC Trigger Interface Chip a proprietary National Instruments ASIC used for direct access to the VXI trigger lines The TIC contains a 16 bit counter a dual 5 bit tick timer and a full crosspoint switch tick The smallest unit of time as measured by an operating system trigger Either TTL or ECL lines used for intermodule communication tristated Defines logic that can have one of three states low high and high impedance TTL Transistor Transistor Logic U unasserted A signal in its inactive false state UINT8 An 8 bit unsigned integer may also be called an unsigned char UINT16 A 16 bit unsigned integer may also be called an unsigned short or word UINT32 A 32 bit unsigned integer may also be called an unsigned long or longword unsigned integer n bit pattern interpreted such that the range is from 0 to 2n 1 UnSupCom Unsupported Command a type of Word Serial Protocol error If a Commander sends a command or query to a Servant which the Servant does not know how to interpret an Unsupported Command protocol error is generated Glossary National Instruments Corporation G 15 NI VXI User Manual V VIC VXI Interactive Control program
66. Manual 3 12 National Instruments Corporation Normally you would use the WSLcmd function to send Longword Serial queries with the response automatically read specified with respflag In cases when you need to inspect the Longword Serial transfer at a lower level however you can break up the query sending and query response retrieval by using the WSLcmd function to send the query as a command and using the WSLresp function to retrieve the response WSLresp polls the RR bit before reading the response from the Data High and Data Low registers to form the 32 bit response After reading the response it polls the Response register until the WR bit is asserted to guarantee that no protocol errors occurred during the transfer WSrd la buf count modevalue retcount WSrd is the word serial buffer read function WSrd reads a specified number of bytes from a Servant device into a local memory buffer using the VXIbus Byte Transfer Protocol The process involves sending a series of Byte Request BREQ Word Serial queries and reading the responses Each response contains a data byte in the lower 8 bits and the END bit in bit 8 Before sending the BREQ command WSrd polls both Response register bits Data Out Ready DOR and Write Ready WR It polls the Response register Read Ready RR bit before reading the response from the Data Low register The read terminates when it receives a maximum number of bytes or if it encounters an END bit a c
67. NI VXI the software distribution actually includes several additional header files along with nivxi h Some of these files have type definitions and macros that can make using NI VXI easier and make the code more portable across different platforms The three main files of interest are datasize h busacc h and devinfo h The datasize h File The datasize h file defines the integer types for use in your program For example INT16 is defined as a 16 bit signed integer and UINT32 is defined as a 32 bit unsigned integer Using these types benefits you by letting you apply specific type sizes across platforms Using undefined types can cause problems when porting your application between platforms For example an int in DOS is a 16 bit number but a 32 bit number in Solaris or LabWindows CVI In addition to the integers datasize h defines several types for other uses such as interrupt handlers For example NIVXI_HVXIINT is an interrupt handler type Merely defining a variable with this type is sufficient to create the function prototype necessary for your interrupt handler Also different platforms require different flags for use with interrupt handlers To simplify this problem datasize h defines NIVXI_HQUAL and NIVXI_HSPEC which are used in the handler definition and take care of the platform dependencies See the Interrupts and Signals section later in this chapter and your read me file for more information In addition refer to Chapter 3
68. PU VXI VME registers On many CPUs the local CPU VXI VME registers cannot be accessed from the local CPU in the A16 address space window due to hardware limitations Another area in the local CPU address space is reserved for accessing the local CPU VXI registers VXIinLR is designed to read these local registers The VXI VME access privilege is not applicable but can be assumed to be Nonprivileged Data The byte order is Motorola Unless otherwise specified reads should always be performed as words This function can be used to read configuration information manufacturer model code and so on for the local CPU VXImemAlloc size useraddr vxiaddr VXImemAlloc allocates physical RAM from the operating system s dynamic memory pool This RAM will reside in the VXI VME Shared RAM region of the local CPU VXImemAlloc returns not only the user address that the application uses but also the VXI VME address that a remote device would use to access this RAM This function is very helpful on virtual memory systems which require contiguous locked down blocks of virtual to physical RAM On non virtual memory systems this function is a malloc standard C dynamic allocation routine and an address translation When the application is finished using the memory it should make a call to VXImemFree to return the memory to the operating system s dynamic memory pool VXImemCopy useraddr bufaddr size dir VXImemCopy copies blocks of memory to
69. Privilege 3 33 UnMapVXIAddress 3 33 VXIpeek 3 33 VXIpoke 3 33 Local Resource Access Functions 3 34 GetMyLA 3 34 ReadMODID 3 34 SetMODID 3 34 VXIinLR 3 35 VXImemAlloc 3 35 VXImemCopy 3 35 VXImemFree 3 35 VXIoutLR 3 36 VXI Signal Functions
70. RR bit before reading the response from the Data Low register After reading the response it polls the Response register until the WR bit is asserted WSsetTmo timo actualtimo WSsetTmo sets the timeout period for all of the Commander Word Serial Protocol functions It sets the timeout value in milliseconds to the nearest resolution of the host CPU When a timeout occurs during a Commander Word Serial Protocol function the function terminates with a corresponding error code WStrg la WStrg sends the Word Serial Trigger command to a message based Servant Before sending the Trigger command by writing to the Data Low register WStrg polls both Response register bits Data In Ready DIR and Write Ready WR until asserted You cannot use the WScmd function to send the Word Serial Trigger command WScmd polls only for WR before sending the command WStrg polls the WR bit until asserted again after sending the Trigger command to guarantee that no protocol errors occurred during the transfer WSwrt la buf count modevalue retcount This function is the buffer write function WSwrt writes a specified number of bytes from a memory buffer to a message based Servant using the VXIbus Byte Transfer Protocol The process involves sending a series of Byte Available BAV Word Serial commands with a single byte in the lower 8 bits of the command Before sending the BAV command WSwrt polls both Response register bits Data In Ready DIR
71. SSwrtHandler 3 20 WSSabort 3 21 WSSdisable 3 21 WSSenable 3 21 WSSLnoResp 3 21 3 22 WSSLsendResp 3 21 WSSrd 3 22 WSSsendResp 3 22 WSSwrt 3 22 SetACfailHandler function 3 65 SetBusErrorHandler function 3 65 to 3 66 SetByteOrder function 3 32 SetContext function 3 32 SetDevInfo function 3 4 SetDevInfoLong function 3 4 SetDevInfoShort function 3 5 SetDevInfoStr function 3 5 SetMODID function 3 34 SetPrivilege function 3 33 SetSignalHandler function 3 41 SetSoftResetHandler function 3 66 SetSysfailHandler function 3 66 SetSysresetHandler function 3 66 SetTrigHandler function 3 56 SetVXIintHandler function 3 50 SetWSScmdHandler function 3 19 to 3 20 Index National Instruments Corporation I 7 NI VXI User Manual SetWSSEcmdHandler function 3 20 SetWSSLcmdHandler function 3 20 SetWSSrdHandler function 3 20 SetWSSwrtHandler function 3 20 Shared Memory events 3 37 3 43 signal handling C C example 2 18 overview 2 17 to 2 18 signal queuing considerations 3 38 to 3 39 SignalDeq function 3 42 SignalEnq function 3 42 SignalJam function 3 42 single tasking operating system support Commander Word Serial Protocol functions 3 7 to 3 8 slave memory access C C example 2 16 to 2 17 overview 2 16 source trigger functions overview 3 57 ScrTrig 3 57 START STOP trigger protocol 3 52 SYNC trigger protocol 3 51 system configuration functions alphabetical list table A 1 CloseVXIlibrary 2
72. Software Overview for specific information Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 10 National Instruments Corporation The busacc h File The busacc h file defines constants and macros for use with the high low level and slave memory access functions see the Master Memory Access and Slave Memory Access sections later in this chapter To make the code more readable busacc h defines such elements as memory space privilege mode and byte order as constants and it defines macros to combine these constants into the necessary access parameters Examine the header file for more information on the available macros and constants You can see these tools in use by reviewing the example programs on memory accesses that appear later in this chapter and also the example programs included with your software The devinfo h File The devinfo h file contains a data type that is used with the GetDevInfo function described in the System Configuration Functions section in Chapter 3 Software Overview The purpose of this function is to return various information about the system GetDevInfo can return the information either a piece at a time or in one large data structure The header file devinfo h contains the type UserLAEntry which defines the data structure that the function uses Refer to the header file for the exact definition of the data structure The Beginning and End of an NI VXI Program All NI VXI progr
73. These devices have a subclass register within their configuration space that defines the type of extended device extended controller The external controller plus all of the extending controllers to which it is directly connected An example is an AT MXI connected to a VXI MXI Extended Longword A form of Word Serial communication in which Commanders and Serial Protocol Servants communicate with 48 bit data transfers extending controller A mainframe extender that has additional VXIbus controller capabilities An example is the VXI MXI external controller A desktop computer or workstation connected to the VXI system via a MXI interface board An example is a standard personal computer with a PCI MXI 2 installed F FHS Fast Handshake a mode of the Word Serial Protocol which uses the VXIbus signals DTACK and BERR for synchronization instead of the Response register bits FIFO First In First Out a method of data storage in which the first element stored is the first one retrieved G GPIB General Purpose Interface Bus the industry standard IEEE 488 bus Glossary National Instruments Corporation G 7 NI VXI User Manual GPIO General Purpose Input Output a module within the National Instruments TIC chip which is used for two purposes First GPIOs are used for connecting external signals to the TIC chip for routing conditioning to the VXIbus trigger lines Second GPIOs are used as part of a crosspoint switch matr
74. TrigSense has configured and enabled the triggering hardware to generate interrupts and the specified trigger protocol is sensed a local CPU interrupt is generated The trigger handler installed is automatically called when a trigger interrupt occurs Chapter 3 Software Overview NI VXI User Manual 3 56 National Instruments Corporation GetTrigHandler line GetTrigHandler returns the address of the current trigger handler for the specified VXI trigger line SetTrigHandler lines func SetTrigHandler replaces the current trigger handler for the specified VXI trigger lines with an alternate handler WaitForTrig controller line timeout You can use the WaitForTrig function to suspend operation until it receives a trigger configured by the EnableTrigSense function After a call to EnableTrigSense for a particular VXI trigger line protocol the trigger handler for a specific trigger line is called when the sourced trigger is sensed from the sourcing device You can use WaitForTrig as an alternate method for receiving sensed triggers by having the caller wait until the trigger occurs instead of installing a callback handler The current handler is invoked regardless of whether a WaitForTrig call is pending Map Trigger Functions You can use the NI VXI map trigger functions as configuration tools for multiframe and local support for VXI triggers You can configure the triggering hardware to route specified source trigger locati
75. VXI devices Commander Word Serial Protocol Functions Word Serial communication is the minimal mode of communication between VXI message based devices within the VXI Commander Servant hierarchy The Commander Word Serial functions let the local CPU the CPU on which the NI VXI interface resides perform VXI message based Commander Word Serial communication with its Servants The four basic types of Commander Word Serial transfers are as follows Command sending Query sending Chapter 3 Software Overview NI VXI User Manual 3 6 National Instruments Corporation Buffer writes Buffer reads The Word Serial Protocol is a 16 bit transfer protocol between a Commander and its Servants The Commander polls specific bits in the Servant s VXI Response register to determine when it can write a command when it can read a response from the Data Low register and when a Word Serial protocol error occurs Before a Commander can send a Word Serial command to a Servant it must first poll the Write Ready WR bit until it is asserted set to 1 The Commander can then write the command to the servant s Data Low register If the Commander is sending a query it first sends the query in the same manner as sending a command but then continues by polling the Read Ready RR bit until it is asserted It then reads the response from the servant s Data Low register A buffer write involves sending a series of Byte Availabl
76. XI Interrupt Functions 3 43 Programming Considerations 3 45 ROAK Versus RORA VXI VME Interrupters 3 46 AcknowledgeVXIint 3 46 AssertVXIint 3 47 DeAssertVXIint 3 47 DefaultVXIintHandler 3 47 DisableVXIint 3 48 DisableVXItoSignalInt 3 48 EnableVXIint 3 48 EnableVXItoSignalInt 3 49 GetVXIintHandler 3 49 RouteVXIint 3 49 SetVXIintHandler
77. YNC protocols at the same time Map a front panel In connector to a TTL or ECL 0 or 1 only trigger line sourcing will be disabled Source a TTL or ECL 0 or 1 only trigger out the front panel Map a TTL or ECL 0 or 1 only trigger line from the backplane out the front panel Out connector accepting disabled Some platforms do not have this capability The following capabilities are not supported Multiple line support Crosspoint switching Signal conditioning External connections other than the front panel In Out Chapter 3 Software Overview NI VXI User Manual 3 54 National Instruments Corporation Embedded External MXI 2 and Remote Controller Trigger Capabilities National Instruments has developed a highly functional ASIC specifically designed for use within the VXIbus triggering environment called the Trigger Interface Chip TIC Note In MXI 2 and the latest embedded systems the TIC has been incorporated into the MANTIS ASIC The TIC chip has access to all of the eight VXI TTL trigger lines two ECL trigger lines ECL0 and ECL1 and 10 external or General Purpose Input Output GPIO connections simultaneously The TIC also contains a 16 bit counter and a dual 5 bit scaler tick timer It contains a full crosspoint switch for routing trigger lines and GPIOs as well as the counter and the tick timers between one another If you want more information on triggering or if
78. ____________________ Company _______________________________________________________________________ Address ________________________________________________________________________ ________________________________________________________________________________ Fax ____ _________________________ Phone ____ ___________________________ Computer brand ___________________ Model ______________ Processor ________________ Operating system include version number ____________________________________________ RAM _____________ MB Display adapter ______________________________________ Mouse ____ yes _____ no Other adapters installed _____________________________ Hard disk capacity ________ MB Brand ____________________________________________ Instruments used __________________________________________________________________ National Instruments hardware product model _____________________ Revision ____________ Configuration ____________________________________________________________________ National Instruments software product ___________________________ Version ____________ Configuration ____________________________________________________________________ The problem is ___________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ______________
79. ________________________________________ If you find errors in the manual please record the page numbers and describe the errors ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ Thank you for your help Name __________________________________________________________________________ Title ___________________________________________________________________________ Company _______________________________________________________________________ Address ________________________________________________________________________ ________________________________________________________________________________ Phone ____ _________________________________________________________________ Mail to Technical Publications Fax to Technical Publications National Instruments Corporation National Instruments Corporation 6504 Bridge Point Parkway 512 794 5678 Austin TX 78730 5039 National Instruments Corporation G 1
80. __________________________________________________________________ List any error messages ____________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ The following steps will reproduce the problem _________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ Documentation Comment Form National Instruments encourages you to comment on the documentation supplied with our products This information helps us provide quality products to meet your needs Title NI VXI User Manual Edition Date July 1996 Part Number 321228A 01 Please comment on the completeness clarity and organization of the manual ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________
81. a from its Commander DIRviol Data In Ready violation A type of word serial protocol error that occurs when the Commander attempts to write data to the device when the device is not ready DOR Data Out Ready This is a bit in the Response register of a message based device that indicates that the device is ready to output data to its Commander DORviol Data Out Ready violation A type of word serial protocol error that occurs when the Commander attempts to read data from the device when the device is not ready DRAM Dynamic RAM Random Access Memory storage that the computer must refresh at frequent intervals DTB See Data Transfer Bus E ECL Emitter Coupled Logic embedded controller A computer plugged directly into the VXI backplane An example is the National Instruments VXIpc 850 END Signals the end of a data string Glossary NI VXI User Manual G 6 National Instruments Corporation EOS End Of String a character sent to designate the last byte of a data message ERR Protocol error Event signal A 16 bit value written to a message based device s Signal register in which the most significant bit bit 15 is a 1 designating an Event as opposed to a Response signal The VXI specification reserves half of the Event values for definition by the VXI Consortium The other half are user defined Extended Class device A class of VXIbus device defined for future expansion of the VXIbus specification
82. a part of the NI VXI bus interface software package Used to program VXI devices and develop and debug VXI application programs Called VICtext when used on text based platforms VME Versa Module Eurocard or IEEE 1014 VMEbus Class device Also called non VXIbus or foreign devices when found in VXIbus systems They lack the configuration registers required to make them VXIbus devices void In the C language a generic data type that can be cast to any specific data type VXIbus VMEbus Extensions for Instrumentation VXIedit VXI Resource Editor program a part of the NI VXI bus interface software package Used to configure the system edit the manufacturer name and ID numbers edit the model names of VXI and non VXI devices in the system as well as the system interrupt configuration information and display the system configuration information generated by the Resource Manager Called vxitedit when used on text based platforms VXItedit Text based version of VXIedit W Word Serial Protocol The simplest required communication protocol supported by message based devices in the VXIbus system It utilizes the A16 communication registers to perform 16 bit data transfers using a simple polling handshake method word A data quantity consisting of 16 bits write Copying data to a storage device WR Write Ready a bit in the Response register of a message based device used in Word Serial Protocol indicating the ability for a Ser
83. a the RouteVXIint function are enabled SetVXIintHandler levels func SetVXIintHandler replaces the current callback handler for the specified VXI VME interrupt levels with an alternate callback handler If VXI VME interrupts are enabled via EnableVXIint the VXI VME interrupt handler for a specific logical address is called The RouteVXIint function must first be called to route VXI VME interrupts to the callback handler as opposed to the signal processing routine A default handler DefaultVXIintHandler is automatically installed when the InitVXIlibrary function is called for every applicable VXI VME interrupt level You can use SetVXIintHandler to install a new callback handler VXIintAcknowledgeMode controller modes VXIintAcknowledgeMode specifies whether to handle the VXI VME interrupt acknowledge cycle for the specified controller embedded or extended for the specified levels as ROAK interrupts or as RORA interrupts If the VXI VME interrupt level is handled as a RORA interrupt the local interrupt generation is automatically inhibited during the interrupt acknowledgment After device specific interaction has caused the deassertion of the interrupt on the backplane your application must call EnableVXIint to re enable the appropriate VXI VME interrupt level Chapter 3 Software Overview National Instruments Corporation 3 51 NI VXI User Manual VXI Trigger Functions VXI triggers are a backplane feature that VXI added
84. ableACfail continued EnableSoftReset EnableSysfail EnableSysreset GetACfailHandler GetBusErrorHandler GetSoftResetHandler GetSysfailHandler GetSysresetHandler SetACfailHandler SetBusErrorHandler SetSoftResetHandler SetSysfailHandler SetSysresetHandler VXI VMEbus MapECLtrig Extender MapTTLtrig MapUtilBus MapVXIint Appendix A Function Classification Reference National Instruments Corporation A 7 NI VXI User Manual Table A 2 Function Listing by Name Function Group VXI VME C C BASIC AcknowledgeTrig Triggers AcknowledgeVXIint VXI VME Interrupt AssertSysreset System Interrupt Handler AssertVXIint VXI VME Interrupt CloseVXIlibrary System Configuration CreateDevInfo System Configuration DeAssertVXIint VXI VME Interrupt DefaultACfailHandler System Interrupt Handler DefaultBusErrorHandler System Interrupt Handler DefaultSignalHandler VXI Signal DefaultSoftResetHandler System Interrupt Handler DefaultSysfailHandler System Interrupt Handler DefaultSysresetHandler System Interrupt Handler DefaultTrigHandler Triggers DefaultTrigHandler2 Triggers DefaultVXIintHandler VXI VME Interrupt DefaultWSScmdHandler Servant Word Serial Protocol DefaultWSSEcmdHandler Servant Word Serial Protocol DefaultWSSLcmdHandler Servant Word Serial Protocol DefaultWSSrdHandler Servant Word Serial Protocol DefaultWSSwrtHandler Servant Word Ser
85. aches the specified count or an error occurs it calls the WSSwrt interrupt handler with the status of the call The default handler sets the global variables WSSwrtDone WSSwrtDoneStatus and WSSwrtDoneCount You can use the variable WSSwrtDone to poll until the operation is complete Afterwards you can inspect WSSwrtDoneStatus and WSSwrtDoneCount to see the outcome of the call If you want you can use the SetWSSwrtHandler function to install an alternate handler GenProtError proterr In response to a Word Serial Protocol Error the application should call GenProtError to generate the error Generating the error consists of preparing the response to a future Read Protocol Error query saving the value in a global variable and setting the ERR bit in the local Response register The RespProtError function actually generates the response when the Read Protocol Error query is received later GetWSScmdHandler GetWSScmdHandler returns the address of the current WSScmd interrupt handler function While Word Serial operations are enabled the WSScmd interrupt handler is called whenever a Word Serial command other than BREQ and BAV is received Chapter 3 Software Overview National Instruments Corporation 3 19 NI VXI User Manual GetWSSEcmdHandler GetWSSEcmdHandler returns the address of the current WSSEcmd interrupt handler function While Word Serial operations are enabled the WSSEcmd interrupt handler will be called every
86. ad pending and cmd is BAV store byte in buffer if done call WSSrdHandler with status set WR and exit else call WSScmdHandler Local VXI Communication Registers Write Data Low High Ext Read Data Low High Response WR RR ERR WSSsendResp WSSLsendResp WSSwrt WSSrd NI VXI Software User Application User ISRs Word Serial Processor RespProtError GenProtError uint16 cmd uint16 cmd uint32 cmd uint16 cmdExt uint32 cmd int16 status uint32 count int16 status uint32 count WSSnoResp WSSLnoResp Figure 3 2 NI VXI Servant Word Serial Model The following paragraphs describe the Servant Word Serial Longword Serial and Extended Longword Serial Protocol functions The descriptions are grouped by functionality and are presented at a functional level describing the operation of each of the functions Chapter 3 Software Overview National Instruments Corporation 3 17 NI VXI User Manual DefaultWSScmdHandler cmd DefaultWSScmdHandler is the default handler for the WSSwrt interrupt which InitVXIlibrary automatically installs when it initializes the NI VXI software The current WSScmdHandler is called whenever the local CPU Commander sends any Word Serial Protocol command or query other than BAV or BREQ While Word Serial operations are enabled the WSScmd interrupt handler is called every time a Word Serial command is received other than BAV if a WSS
87. address selected has no device residing at the address and a bus error occurs VXIout traps the bus error condition and indicates the error through the return status VXIoutReg la reg value VXIoutReg writes a single word to a particular VXI device s VXI registers within the logical address space the upper 16 KB of VXI A16 address space The function sets the VXI access privilege to Nonprivileged Data and the byte order to Motorola If the VXI address selected has no device residing at the address and a bus error occurs VXIinReg traps the bus error condition and indicates the error through the return status This function is mainly for convenience and is a layer on top of VXIoutLR and VXIout If the la specified is the local CPU logical address it calls the VXIoutLR function Otherwise it calculates the A16 address of the VXI device s register and calls VXIout Note VXIoutReg is designed to access a VXIbus device configuration register and therefore is not applicable to VME devices Chapter 3 Software Overview NI VXI User Manual 3 26 National Instruments Corporation Low Level VXI VMEbus Access Functions This section describes the use of the low level VXI VMEbus access functions You can use both low level and high level VXI VMEbus access functions to directly read or write to VXI VMEbus addresses Some of the situations that require direct reads and writes to the different VXI VMEbus address spaces include the following
88. after processing a Word Serial command it calls WSSsendResp for a Word Serial query which requires a response WSSrd buf count modevalue WSSrd is the buffer read function WSSrd receives a specified number of bytes from a VXI message based Commander device and places the bytes into a memory buffer using the VXIbus Byte Transfer Protocol The process involves setting the DIR and WR bits on the local CPU Response register and building a buffer out of data bytes received via a series of Byte Available BAV Word Serial commands When WSSrd reaches the specified count or an END bit or an error occurs it calls the WSSrd interrupt handler with the status of the call It clears the DIR bit before setting the WR on the last byte of transfer WSSsendResp response WSSsendResp responds to a Word Serial Protocol query from a VXI message based Commander device The WSScmd interrupt handler calls this function to respond to a Word Serial query If a previous response has not been read yet a WSSsendResp call generates a Multiple Query Error MQE Otherwise it writes a response value to the Data Low register and sets the RR bit is It also sets the WR bit so that it is ready to accept any further Word Serial commands WSSwrt buf count modevalue WSSwrt sends a specified number of bytes to a VXI message based Commander device using the VXIbus Byte Transfer Protocol The process involves setting the DOR and WR bits in the local Response re
89. ained The write to the Reset bit causes an interrupt on the local CPU which can be handled in any appropriate manner The CPU cannot restart operation until the Reset bit is cleared After the Reset bit is cleared the local CPU can go through a reinitialization process or reboot altogether If the local CPU is the Resource Manager and top level Commander the Reset bit should never be written Writing the Reset bit of any device should be reserved for the Commander of the device Note The Soft Reset interrupt does not apply to VME EnableSysfail controller EnableSysfail sensitizes the application to Sysfail interrupts from embedded controller or extended controller s Sysfail conditions dependent on the hardware platform and configuration The VXIbus Chapter 3 Software Overview NI VXI User Manual 3 64 National Instruments Corporation specification requires that all VXI Commanders monitor the PASSed or FAILed state of their VXI Servants When a VXIbus device is in the FAILed state the failed device clears its PASS bit in its Status register and asserts the SYSFAIL signal on the VXIbus backplane When a Sysfail condition is detected on the local CPU an interrupt is generated and the current Sysfail interrupt handler is called The failed Servant device must be forced offline or brought back online in an orderly fashion EnableSysreset controller EnableSysreset sensitizes the application to Sysreset interrupts from
90. alled configuration registers Figure 1 1 These registers are located in the upper 16 KB of the 64 KB A16 VME address space The logical address of a VXI device determines the location of the device s configuration registers in the 16 KB area reserved by VXI Chapter 1 Overview of NI VXI NI VXI User Manual 1 2 National Instruments Corporation Reserved Reserved Reserved Reserved Data Low Data High Response Data Extended Protocol Signal Offset Status Control Device Type ID Register VXI Configuration Space Offset 3F 20 IE 1C 1A 18 0E 0C 0A 08 06 04 02 00 Upper 16 KB of A16 space reserved for VXI configuration space 64 bytes per device 8 bit logical address specifies base address for each device 256 devices per VXI system Device Dependent Registers Reserved by VXIbus Specification A32 Pointer Low A32 Pointer High A24 Pointer Low A32 Pointer High 16 14 12 10 Shared Memory Protocol Registers Communication Registers Required for VXI Message Based Devices Configuration Registers Required for all VXI Devices Figure 1 1 VXI Configuration Registers Register Based Devices Through the use of the VXI configuration registers which are required for all VXI devices the system can identify each VXI device its type model and manufacturer address space and memory requirements VXIbus devices with only this minim
91. ams must call InitVXIlibrary to initialize the driver before using any other functions You must call CloseVXIlibrary before exiting from your program to free resources associated with NI VXI The first function creates the internal structure needed to make the NI VXI interface operational When InitVXIlibrary completes its initialization procedures other functions can access information obtained by RESMAN the VXIbus Resource Manager as well as use other NI VXI features such as interrupt handlers and windows for memory access The second function destroys this structure and frees the associated memory All programs using NI VXI must call InitVXIlibrary before any other NI VXI function In addition your program should include a call to CloseVXIlibrary before exiting Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 11 NI VXI User Manual An important note about these two functions is that the internal structure maintains a record of the number of calls to InitVXIlibrary and CloseVXIlibrary Although InitVXIlibrary needs to be called only once the structure of your program may cause the function to be called multiple times A successful call to InitVXIlibrary returns either a zero or a one A zero indicates that the structure has been created and a one indicates that the structure was created by an earlier call so no action was taken other than incrementing the count of the number of Ini
92. an handle the signals either at interrupt service routine time or by queueing on a global signal queue For each VXI logical address the RouteSignal function specifies which types of signals should be handled by the handlers and which should be queued on the global signal queue A separate handler can be installed for each VXI logical address present see the description of SetSignalHandler The InitVXIlibrary function automatically installs a default handler DefaultSignalHandler for every VXI logical address If signals are queued the application can use the SignalDeq or WaitForSignal function to selectively return a signal off a global signal queue by VXI logical address and or type of signal The default for RouteSignal is to have all signals routed to interrupt service routines SetSignalHandler la func SetSignalHandler replaces the current signal handler for the specified VXI logical address with an alternate handler If signal interrupts are enabled via EnableSignalInt the signal handler for a specific logical address is called if the RouteSignal function has been set up to route signals to the handler as opposed to the global signal queue The InitVXIlibrary function automatically installs a default handler DefaultSignalHandler for every VXI logical address The logical address la value of 2 is a special case and is provided to specify a handler to capture signals from devices not known to the device information table Thi
93. and the local CPU Shared RAM These functions are useful for shared memory type communication non Resource Manager operation and debugging purposes The following paragraphs describe the local resource access functions The descriptions are presented at a functional level describing the operation of each of the functions The functions are grouped by area of functionality GetMyLA GetMyLA retrieves the logical address of the local VXI VME device The local CPU VXI VME logical address is required for retrieving configuration information with one of the GetDevInfo functions The local CPU VXI VME logical address is also required for creating correct VXI signal values to send to other devices ReadMODID modid ReadMODID senses the MODID line drivers of the local CPU when configured as a VXI Slot 0 device The modid output parameter returns the polarity of each of the slot s MODID lines SetMODID enable modid SetMODID controls the MODID line drivers of the local CPU when configured as a VXI Slot 0 device The enable parameter enables the MODID drivers for all the slots The modid parameter specifies which slots should have their corresponding MODID lines asserted Note The MODID lines are unique to the VXIbus and has no meaning on a VMEbus Chapter 3 Software Overview National Instruments Corporation 3 35 NI VXI User Manual VXIinLR reg width value VXIinLR reads a single byte word or longword from the local C
94. andler 3 60 to 3 61 DefaultSignalHandler function 3 40 DefaultSoftResetHandler function 3 61 DefaultSysfailHandler function 3 61 to 3 63 DefaultTrigHandler function 3 55 DefaultTrigHandler2 function 3 55 DefaultVXIntHandler function 3 47 to 3 48 DefaultWSScmdHandler function 3 17 DefaultWSSEcmdHandler function 3 17 DefaultWSSLcmdHandler function 3 17 to 3 18 DefaultWSSrdHandler function 3 18 DefaultWSSwrtHandler function 3 18 devinfo h file 2 10 DisableSignalInt function description 3 40 signal queuing considerations 3 38 DisableSysreset function 3 63 DisableTrigSense function 3 55 DisableVXIint function 3 48 DisableVXItoSignalInt function description 3 48 signal queuing considerations 3 38 documentation conventions used in manual xiv organization of manual xiii xiv related documentation xv E e mail support B 2 electronic support services B 1 to B 2 embedded controller 2 5 EnableACfail function 3 63 EnableSignalInt function 3 40 EnableSoftReset function 3 63 EnableSysfail function 3 63 to 3 64 EnableSysreset function 3 64 EnableTrigSense function 3 55 EnableVXIint function 3 48 to 3 49 EnableVXItoSignalInt function 3 49 ERR bit 3 6 3 15 Event signals 3 37 Event status IDs 3 43 Extended Longword Serial Protocol 3 7 3 15 extender parameters 2 7 to 2 8 Index National Instruments Corporation I 3 NI VXI User Manual external controllers 2 6 to 2 7 definition 2 6 embeddded con
95. arriage return CR a line feed LF or a user specified termination character WSrdf la filename count modevalue retcount WSrdf is an extension of the WSrd function WSrdf reads a specified number of bytes from a Servant device into the specified file using the VXIbus Byte Transfer Protocol The process involves calling the function WSrd possibly many times to read in a block of data and writing the data to the specified file The read terminates when it receives a maximum number of bytes or if it encounters an END bit a carriage return CR a line feed LF or a user specified termination character WSresp la response WSresp retrieves a response to a previously sent Word Serial Protocol query from a VXI message based Servant Note This function is intended only for debugging purposes Chapter 3 Software Overview National Instruments Corporation 3 13 NI VXI User Manual Normally you would use the WScmd function to send Word Serial queries with the response automatically read specified with respflag In cases when you need to inspect the Word Serial transfer at a lower level however you can break up the query sending and query response retrieval by using the WScmd function to send the query as a command and using the WSresp function to retrieve the response During the interim period between sending the WScmd and WSresp functions you can check register values and other hardware conditions WSresp polls the
96. as well as the cause of the event See the VXI Interrupt Functions section in Chapter 3 Software Overview for more information Handling either signals or interrupts through the signal queue is very straightforward You can use the RouteVXIint and RouteSignal functions to specify that the events should be handled by the signal queue After you have enabled the event handler through either the EnableSignalInt or the EnableVXItoSignalInt call the event is placed on the queue when it occurs You can use the SignalDeq or WaitForSignal functions to retrieve the event from the queue Note RESMAN allocates interrupt lines to VXI devices that support the programmable interrupt command Devices should use only those interrupt lines allocated to them Again you can use GetDevInfo to determine what interrupt lines have been allocated to the controller Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 18 National Instruments Corporation Alternatively you can choose to handle either signals or interrupts with a callback handler You can use RouteSignal to specify that the events should be handled by the callback handlers rather than the signal queue After you have enabled the callback handler through either the EnableSignalInt or the EnableVXIint call the callback function will be invoked when the event occurs Installing and using callback handlers is very simple with NI VXI because all of the operatin
97. ation Low Level VXIbus Access Functions Low level VXI VMEbus access functions are the fastest access method for directly reading from or writing to any of the VXI VMEbus address spaces You can use these functions to obtain a pointer that is directly mapped to a particular VXI VMEbus address Then you use the pointer with the low level VXI VMEbus access functions to read from or write to the VXI VMEbus address space When using these functions in your application you need to consider certain programming constraints and error conditions such as bus errors BERR Local Resource Access Functions Local resource access functions let you access miscellaneous local resources such as the local CPU VXI register set Slot 0 MODID operations when the local device is configured for Slot 0 operation and the local CPU VXI Shared RAM These functions are useful for shared memory type communication for the non Resource Manager operation when the local CPU is not the Resource Manager and for debugging purposes VXI Signal Functions VXI signals are a method for VXI bus masters to interrupt another device You can route VXI signals to a handler or queue them on a global signal queue You can use these functions to specify the signal routing install handlers manipulate the global signal queue and wait for a particular signal value or set of values to be received Note Although signals are defined in the VXI specification VME
98. ation in the NI VXI interface and can affect execution At the startup of your application InitVXIlibrary completely initializes the RM table according to how the RM configured the VXI system No initial changes are necessary for VXI devices SetDevInfoLong la field longvalue SetDevInfoLong changes information about the specified device in the NI VXI RM table The field parameter specifies the attribute of the information to change SetDevInfoLong is a function layered on top of SetDevInfo for languages such as BASIC that cannot typecast the fieldvalues of SetDevInfo SetDevInfoLong returns only the fields of SetDevInfo that are 32 bit integers Possible fields include the VXI address base and size allocated to the device by the RM You should use this function only in very special situations because it updates information in the NI VXI interface and can affect execution At the startup of your application InitVXIlibrary completely initializes the RM table to how the RM configured the VXI system No initial changes are necessary for VXI devices Chapter 3 Software Overview National Instruments Corporation 3 5 NI VXI User Manual SetDevInfoShort la field shortvalue SetDevInfoShort changes information about the specified device in the NI VXI RM table The field parameter specifies the attribute of the information to change SetDevInfoShort is a function layered on top of SetDevInfo for languages such as BASIC that cannot typ
99. ble command Used to transfer 8 bits of data from a Commander to its Servant under the Word Serial Protocol BERR Bus error signal This signal is asserted by either a slave device or the bus time out BTO unit when an incorrect transfer is made on the Data Transfer Bus DTB The BERR signal is also used in VXI for certain protocol implementations such as writes to a full Signal register and synchronization under the Fast Handshake Word Serial Protocol binary A numbering system with a base of 2 bit Binary digit The smallest possible unit of data a two state yes no 0 1 alternative The building block of binary coding and numbering systems Several bits make up a byte bit vector A string of related bits in which each bit has a specific meaning BREQ Word Serial Byte Request query Used to transfer 8 bits of data from a Servant to its Commander under the Word Serial Protocol BTO See bus timeout unit buffer Temporary memory storage location for holding data before it can be transmitted elsewhere bus master A device that is capable of requesting the Data Transfer Bus DTB for the purpose of accessing a slave device bus timeout unit A VMEbus functional module that times the duration of each data transfer on the Data Transfer Bus DTB and terminates the DTB cycle if the duration is excessive Without the termination capability of this module a bus master could attempt to access a nonexistent slave resulting in an i
100. cast the fieldvalues of GetDevInfo GetDevInfoLong returns only the fields of GetDevInfo that are 32 bit integers Possible fields include the VXI address base and size allocated to the device by the RM GetDevInfoShort la field shortvalue GetDevInfoShort returns information about the specified device from the NI VXI RM table The field parameter specifies the attribute of the information to retrieve GetDevInfoShort is a function layered on top of GetDevInfo for languages such as BASIC that cannot typecast the fieldvalues of GetDevInfo GetDevInfoShort returns only the fields of GetDevInfo that are 16 bit integers Possible fields include the Commander s logical address mainframe number slot manufacturer ID number manufacturer name model code device class VXI address space allocated VXI interrupt lines handlers allocated protocols supported and so on GetDevInfoStr la field stringvalue GetDevInfoStr returns information about the specified device from the NI VXI RM table The field parameter specifies the attribute of the information to retrieve GetDevInfoStr is a function layered on top of GetDevInfo for languages such as BASIC that cannot typecast the fieldvalues of GetDevInfo GetDevInfoStr returns only the fields of GetDevInfo that are character strings Possible fields include the device name manufacturer name and model name Chapter 3 Software Overview NI VXI User Manual 3 4 National Instruments Corpora
101. ce that the default controller is determined by the following factors If the program is running on an embedded controller the default controller is the embedded controller If the program is running on an external controller you will be able to configure whether the default controller is the external controller or the remote controller with the lowest numbered logical address With this behavior if you write a program on an embedded controller referring to the controller as logical address 1 you will be able to swap the embedded controller configuration with an external controller configuration without changing your source code Notice that 1 is never a valid value for the extender parameter In addition the logical addresses of embedded and external controllers also are never valid values for the extender parameter The extender parameter refers only to devices that can map interrupt lines trigger lines or other signals into or out of a frame Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 9 NI VXI User Manual Using NI VXI This section presents a general overview of the more commonly used class of functions available in NI VXI Additional information summarizes how you can use the functions to perform certain tasks and further describes the general structure of NI VXI programming Header Files Although nivxi h is the only header file you need to include in your program for
102. ceive and process any one of these commands Programming Considerations Most of the Servant Word Serial functions require an interrupt handler The word serial commands must be parsed and responded to within the appropriate interrupt handler Word Serial commands Byte Available BAV and Byte Request BREQ are handled as a special case for reads and writes For reads and writes a user supplied handler is notified only that the transfer is complete and not for each byte processed Asserting and unasserting of all Response register bits Chapter 3 Software Overview NI VXI User Manual 3 16 National Instruments Corporation DIR DOR WR RR and ERR are done automatically within the functions as required Figure 3 2 provides a graphical overview of the Servant Word Serial functions ERROR Hardware WSScmdHandler NI VXI base Interrupt Service Routine ISR WSSenable WSSdisable SetWSScmdHandler GetWSScmdHandler DefaultWSScmdHandler Read Command WSSLcmdHandler WSSrdHandler WSSEcmdHandler WSSwrtHandler SetWSSwrtHandler GetWSSwrtHandler DefaultWSSwrtHandler SetWSSrdHandler GetWSSrdHandler DefaultWSSrdHandler SetWSSLcmdHandler GetWSSLcmdHandler DefaultWSSLcmdHandler SetWSSLcmdHandler GetWSSLcmdHandler DefaultWSSLcmdHandler WSS WSSL WSSE if write pending and cmd is BREQ respond with next byte if done call WSSwrtHandler with status set WR and exit else if re
103. controller DeAssertVXIint can be used to unassert a VXI VME interrupt that was asserted using the AssertVXIint function AcknowledgeVXIint can be used to acknowledge VXI VME interrupts that the local CPU is not enabled to automatically handle via EnableVXIint or EnableVXItoSignalInt Both Chapter 3 Software Overview National Instruments Corporation 3 45 NI VXI User Manual DeAssertVXIint and AcknowledgeVXIint are intended only for debugging purposes Programming Considerations Figure 3 4 is a graphical overview of the NI VXI interrupt and signal model RouteVXIint VXI VME Interrupts 1 7 Hardware NI VXI Software User Application VXIintHandlers SignalHandlers NI VXI base Interrupt Service Routines ISR Local VXI Signals EnableSignalInt DisableSignalInt RouteSignal EnableVXIint DisableVXIint EnableVXItoSignalInt DisableVXItoSignalInt SetVXIintHandler GetVXIintHandler DefaultVXIintHandler SignalEnq User ISRs 1 per VXI VME interrupt level 1 per logical address SetSignalHandler GetSignalHandler DefaultSignalHandler Signal Processor Signal Queue WaitForSignal If signal not on queue enable monitor block till received else SignalDeq return signal mask SignalDeq uint16 signal SignalEnq SignalDeq SignalJam uint16 statusId WaitForSignal uint16 level uint32 statusId uint16 signal uint16 signal Get Si
104. customers may still use the signal register available on any VXI VME MXI hardware This register provides a simple notification mechanism that can be used by any bus master VXI VME Interrupt Functions By default interrupts are processed as VXI signals either with a handler or by queuing on the global signal queue The VXI VME interrupt functions can specify the processing method and install interrupt service routines In addition the VXI VME interrupt functions can assert specified VXI VME interrupt lines with a specified status ID value System Interrupt Handler Functions The system interrupt handler functions let you install handlers for the various system interrupt conditions These conditions include Sysfail ACfail bus error and soft reset interrupts VXI VMEbus Extender Functions The VXI VMEbus extender functions can dynamically configure multiple mainframe mappings Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 3 NI VXI User Manual of the VXI VME interrupt lines VXI TTL triggers VXI ECL triggers and utility bus signals The National Instruments Resource Manager configures the mainframe extenders with settings based on user modifiable configuration files VXI Only Function Groups The following NI VXI function groups do not apply to VME Commander Word Serial Protocol Functions Word Serial is a form of communication between VXI message based devices T
105. d The default handler puts the status and read count in a global variable and flags the operation complete SetWSSwrtHandler func SetWSSwrtHandler replaces the current WSSwrt interrupt handler with an alternate handler When WSSwrt reaches the specified count or an error occurs it calls the WSSwrt interrupt handler with the status of the call The DOR bit will be cleared before WR is set on the last byte of transfer InitVXIlibrary automatically installs a default handler DefaultWSSwrtHandler when it initializes the NI VXI software The default handler puts the status and read count in a global variable and flags the operation complete Chapter 3 Software Overview National Instruments Corporation 3 21 NI VXI User Manual WSSabort abortop WSSabort aborts the Servant Word Serial operation s in progress It returns an error code of ForcedAbort to the WSSrd or WSSwrt interrupt handlers in response to the corresponding pending functions This may be necessary if the application needs to abort for some application specific reason or if the Commander of this device sends a Word Serial Clear End Normal Operation or Abort command WSSdisable WSSdisable disables all Servant Word Serial functions from being used More precisely this function desensitizes the local CPU to interrupts generated when writing a Word Serial command to the Data Low register or reading a response from the Data Low register WSSenable WSSenabl
106. e BAV Word Serial commands to the Servant with the additional constraint that the Data In Ready DIR bit as well as the WR bit be asserted before sending the Byte Available The lower 8 bits bits 0 to 7 of the 16 bit command contain a single byte of data bit 8 is the END bit Therefore one Byte Available is sent for each data byte in the buffer written A buffer read involves sending a series of Byte Request BREQ Word Serial queries to the Servant with the additional constraint that the Data Out Ready DOR bit as well as the WR bit must be asserted before sending the Byte Request The lower 8 bits bits 0 to 7 of the 16 bit response contain a single byte of data bit 8 is the END bit Therefore one Byte Request is sent for each data byte in the buffer read In addition to the WR RR DIR and DOR bits that get polled during various Word Serial transfers the functions also check the ERR bit The ERR bit indicates when a Word Serial Protocol error occurs The Word Serial Protocol errors are Unsupported Command Multiple Query Error MQE DIR Violation DOR Violation RR Violation or WR Violation After the Servant asserts the ERR bit the application can determine the actual error that occurred by sending a Read Protocol Error query to the Servant The NI VXI Word Serial functions query the Servant automatically and return the appropriate error codes to the caller at which time the Servant deasserts the ERR bit Chapter 3 S
107. e application to specified interrupt levels being processed as VXI signals After calling InitVXIlibrary the application can sensitize itself to interrupt levels for which it is configured to handle RouteVXIint specifies whether interrupts are to be handled as VXI VME interrupts or as VXI signals the default is VXI signals An EnableVXItoSignalInt call enables interrupt levels that are routed to VXI signals Use DisableVXItoSignalInt to disable these VXI interrupts Use EnableVXIint to enable interrupts not routed to VXI signals A 1 negative one or local logical address in the controller parameter specifies the local embedded controller or the first extended controller in an external controller situation If a RouteVXIint call has specified to route a particular VXI VME interrupt level to the VXI signal processing routine and the global signal queue becomes full DisableVXItoSignalInt is automatically called to inhibit these VXI interrupts from being received from the appropriate levels EnableVXItoSignalInt is automatically called to enable VXI VME interrupt reception when SignalDeq is called GetVXIintHandler level GetVXIintHandler returns the address of the current VXI VME interrupt handler routine for the specified interrupt level If interrupts are enabled via EnableVXIint the callback handler for a specific logical address is called You must first call RouteVXIint to route VXI VME interrupts to the callback handler as opposed
108. e condition occurs for the system to remain operational The detection of the power failure asserts the VXI VMEbus backplane signal ACFAIL An ACfail condition detected on the local CPU generates an interrupt that calls the current ACfail interrupt handler Your application can take any appropriate action within the allotted time period before complete power failure DisableSoftReset DisableSoftReset desensitizes the application to Soft Reset conditions on the local CPU When the Reset bit in the VXI Control register of the local CPU is written the VXI interface if an embedded CPU and the VXI register sets are reset VXI logical address and address base are retained The write to the Reset bit causes an interrupt on the local CPU which can be handled in any appropriate manner The CPU cannot restart operation until the Reset bit is cleared After the Reset bit is cleared the local CPU can go through a reinitialization process or reboot altogether If the local CPU is the Resource Manager and top level Commander the Reset bit should never be written Writing the Reset bit of any device should be reserved for the Commander of the device Note The Soft Reset interrupt does not apply to VME DisableSysfail controller DisableSysfail desensitizes the application to Sysfail interrupts from embedded controller or extended controller s Sysfail conditions dependent on the hardware platform The VXIbus specification requires that al
109. e enables all Servant Word Serial functions More precisely this function sensitizes the local CPU to interrupts generated when writing a Word Serial command to the Data Low register or reading a response from the Data Low register By default the Servant Word Serial functions are disabled At any time after InitVXIlibrary initializes the NI VXI software you can call WSSenable to set up processing of Servant Word Serial commands and queries WSSLnoResp WSSLnoResp sets the WR bit so that it is ready to accept any further Longword Serial commands The WSSLcmd interrupt handler should call WSSLnoResp after processing a Longword Serial command it calls WSSLsendResp for Longword Serial queries WSSLsendResp response WSSLsendResp responds to a Longword Serial Protocol query from a VXI message based Commander device The WSSLcmd interrupt handler calls this function to respond to a Longword Serial query If a previous response has not been read yet a WSSLsendResp call generates a Multiple Query Error MQE Otherwise it writes a response value to the Data High and Data Low registers and sets the RR bit It also sets the WR bit so that it is ready to accept any further Word Serial commands Chapter 3 Software Overview NI VXI User Manual 3 22 National Instruments Corporation WSSnoResp WSSnoResp sets the WR bit so that it is ready to accept any further Word Serial commands The WSScmd interrupt handler should call WSSnoResp
110. e lower 8 bits form the VXI logical address of the interrupting device and the upper 8 bits specify the reason for interrupting STST START STOP trigger protocol a one line multiple device protocol that can be sourced only by the VXI Slot 0 device and sensed by any other device on the VXI backplane supervisory access One of the defined types of VMEbus data transfers indicated by certain address modifier codes synchronous A communications system that follows the command response cycle communications model In this model a device issues a command to another device the second device executes the command and then returns a response Synchronous commands are executed in the order they are received SYNC Protocol The most basic trigger protocol simply a pulse of a minimum duration on any one of the trigger lines SYSFAIL A VMEbus signal that is used by a device to indicate an internal failure A failed device asserts this line In VXI a device that fails also clears its PASSed bit in its Status register SYSRESET A VMEbus signal that is used by a device to indicate a system reset or power up condition system clock driver A VMEbus functional module that provides a 16 MHz timing signal on the utility bus Glossary NI VXI User Manual G 14 National Instruments Corporation System Controller A functional module that has arbiter daisy chain driver and MXIbus cycle timeout responsibility Always the first device in the
111. e trigger line and a STOP condition is generated on the unassertion edge of the trigger line ON OFF ON OFF protocol is identical to the START STOP protocol The VXIbus specification however defines START STOP such that only Slot 0 may assert START STOP Therefore ON OFF protocols are outside the VXIbus specifications but provide similar functionality You can use these protocols in any way that your application requires You can use them for device synchronization for stepping through tests or for a command path The NI VXI trigger functions have been designed to accommodate all trigger lines and the protocols for all appropriate TTL and ECL VXI trigger lines SYNC ASYNC SEMI SYNC START STOP and ON OFF The VXI trigger functions have been grouped into the following four categories Source trigger functions Acceptor trigger functions Map trigger functions Trigger configuration functions The actual capabilities of specific systems are based on the triggering capabilities of the hardware devices involved both the sourcing and accepting devices All of the NI VXI functions have appropriate error response for unsupported capabilities Capabilities of the National Instruments Triggering Hardware The NI VXI trigger functions are a general purpose interface designed to accommodate most uses of VXI triggers The actual capabilities of a particular platform will always be a subset of these capabiliti
112. ecast the fieldvalues of SetDevInfo SetDevInfoShort changes only the fields of SetDevInfo that are 16 bit integers Possible fields include the Commander s logical address mainframe number slot manufacturer ID number model code device class VXI address space allocated VXI interrupt lines handlers allocated protocols supported and so on You should use this function only in very special situations because it updates information in the NI VXI interface and can affect execution At the startup of your application InitVXIlibrary completely initializes the RM table to how the RM configured the VXI system No initial changes are necessary for VXI devices SetDevInfoStr la field stringvalue SetDevInfoStr changes information about the specified device in the NI VXI RM table The field parameter specifies the attribute of the information to change SetDevInfoStr is a function layered on top of SetDevInfo for languages such as BASIC that cannot typecast the fieldvalues of SetDevInfo SetDevInfoStr returns only the fields of SetDevInfo that are character strings Possible fields include the device name manufacturer name and model name You should use this function only in very special situations because it updates information in the NI VXI interface and can affect execution At the startup of your application InitVXIlibrary completely initializes the RM table to how the RM configured the VXI system No initial changes are necessary for
113. end read write or trigger calls in progress Chapter 3 Software Overview National Instruments Corporation 3 9 NI VXI User Manual Figure 3 1 gives a precise description of this two level mutual exclusion algorithm Notice that this mutual exclusion is on a per logical address basis Any number of logical addresses can have Word Serial transfers in progress without conflict If the application is to be compatible with IEEE 488 2 the application must perform trigger and write calls in sequential order WSwrt WSwrtf WStrg WSrd WSrdf Wrt and Trg Exclusion Write and trigger ordering for IEEE 488 2 compatible operation must be done by the application No attempt is made to order or perform mutual exclusion between write and trigger calls In addition no mutual exclusion is done between multiple writes or multiple triggers No more than one write or trigger call may be pending at any one time per logical address Local CPU VXI A16 Window VXIbus Remote Word Serial Hardware WScmd WSclr WSLcmd WSEcmd Rd Wrt Trg Exclusion Command Priority Override All Word Serial command functions have priority over the read and write functions If a command call is underway all read and write calls will be suspended until the command transfer is complete If a read or write call is already underway when a command call is made the command call will cause the read or write call to suspend before the next individual read or write
114. epat manid modelcode devclass slot mainframe cmdrla la FindDevLA scans the RM table information for a device with the specified attributes and returns its VXI logical address You can use any combination of attributes to specify a device A 1 negative one or specifies to ignore the corresponding field in the attribute comparison After finding the VXI logical address you can use one of the GetDevInfo functions to get any information about the specified device Chapter 3 Software Overview National Instruments Corporation 3 3 NI VXI User Manual GetDevInfo la field fieldvalue GetDevInfo returns information about the specified device from the NI VXI RM table The field parameter specifies the attribute of the information to retrieve Possible fields include the device name Commander s logical address mainframe number slot manufacturer ID number model code model name device class VXI address space base size allocated VXI interrupt lines handlers allocated protocols supported and so on A field value of zero 0 specifies to return a structure containing all possible information about the specified device GetDevInfoLong la field longvalue GetDevInfoLong returns information about the specified device from the NI VXI RM table The field parameter specifies the attribute of the information to retrieve GetDevInfoLong is a function layered on top of GetDevInfo for languages such as BASIC that cannot type
115. er when it initializes the NI VXI software Your application must then call EnableACfail to enable ACfail interrupts SetBusErrorHandler func SetBusErrorHandler replaces the current bus error interrupt handler with an alternate handler During an access to the VXI VMEbus the BERR signal bus error is asserted to end the bus cycle if the address or mode of access is determined to be invalid The bus error exception condition generates an exception on the local CPU which can be trapped by the bus error handler Your application should include a retry mechanism if it is possible for a particular access to generate bus Chapter 3 Software Overview NI VXI User Manual 3 66 National Instruments Corporation errors at times and valid results at other times The InitVXIlibrary function automatically installs a default handler DefaultBusErrorHandler when it initializes the NI VXI software Because bus errors can occur at any time a corresponding enable and disable function is not possible SetSoftResetHandler func SetSoftResetHandler replaces the current Soft Reset interrupt handler with an alternate handler A default handler DefaultSoftResetHandler is automatically installed when InitVXIlibrary initializes the NI VXI software EnableSoftReset must be called to enable writes to the Reset bit to generate interrupts to the local CPU after the InitVXIlibrary call Note The Soft Reset interrupt does not apply to VME SetSysfai
116. ervant hierarchies 1 4 Commander Word Serial communication Extended Longword Serial Protocol 3 7 Longword Serial Protocol 3 7 overview 2 13 3 5 to 3 7 polling operations 3 6 special cases 3 7 types of transfers 3 5 to 3 6 Word Serial Protocol 3 6 Commander Word Serial Protocol functions alphabetical list table A 2 cooperative multitasking support 3 7 to 3 8 interrupt service routine support 3 7 to 3 8 multitasking support preemptive operating system 3 8 to 3 10 overview 2 3 programming considerations 3 7 single tasking operating system support 3 7 to 3 8 WSabort 3 8 3 10 WSclr 3 10 Index NI VXI User Manual I 2 National Instruments Corporation WScmd 3 10 WSEcmd 3 11 WSgetTmo 3 11 WSLcmd 3 11 WSLresp 3 11 to 3 12 WSrd 3 12 WSrdf 3 12 WSresp 3 12 to 3 13 WSsetTmo 3 13 WStrg 3 13 WSwrt 3 13 WSwrtf 3 14 configuration functions See system configuration functions trigger configuration functions controller parameters 2 7 to 2 8 controllers 2 5 to 2 7 definition 2 5 embedded controller 2 5 external controller 2 6 to 2 7 remote controller 2 5 to 2 6 cooperative multitasking support Commander Word Serial Protocol functions 3 7 to 3 8 CreateDevInfo function 3 2 customer communication xv B 1 to B 2 D Data in Ready DIR bit 3 6 3 15 Data Out Ready DOR bit 3 6 3 15 datasize h file 2 9 DeAssertVXIint function 3 47 DefaultACfailHandler function 3 60 DefaultBusErrorH
117. ervice routine to invoke In VXI systems however the VXI interrupt acknowledge cycle returns at a minimum a 16 bit status ID value This 16 bit status ID value is data not a vector base location The definition of the 16 bit value is specified by the VXIbus specification and is the same as for the VXI signal The lower 8 bits of the status ID value form the VXI logical address of the interrupting device while the upper 8 bits specify the reason for interrupting VXI status ID values from message based devices can be one of two types Response status IDs and Event status IDs bit 15 distinguishes between the two Response status IDs are used to report changes in Word Serial communication status between a Servant and its Commander Event status IDs are used to inform another device of other asynchronous changes The four Event status IDs currently defined by the VXIbus specification other than Shared Memory Events are No Cause Given Request for Service True REQT Request for Service False REQF and Unrecognized Command REQT and REQF are used to manipulate the SRQ condition RSV bit assertion in the IEEE 488 488 2 status byte while Unrecognized Command is used to report unsupported Word Serial commands only in VXIbus specification Revision 1 2 If the VXI interrupt status ID value is from a register based device the upper 8 bits are device dependent Consult your device manual for definitions of these values Because the VXI inte
118. es In Chapter 3 Software Overview National Instruments Corporation 3 53 NI VXI User Manual general however National Instruments hardware has two current configurations that provide triggering functionality Trigger control used on a VXI MXI 1 frame extender when used as an extending controller under direct control of a root level MXI 1 controller interface such as an AT MXI 1 These configurations do not have the National Instruments Trigger Interface Chip TIC on them Note VXI MXI 1 and VXI MXI 2 controllers that are configured for extender only that is not extending controllers as well as external MXI 1 controllers do not have trigger functionality See the section Multiple Mainframe Support in Chapter 2 Introduction to the NI VXI Functions for more information An embedded controller external MXI 2 controllers or VXI MXI 2 remote controllers These configurations do have the National Instruments Trigger Interface Chip TIC on them External Controller VXI MXI 1 Trigger Capabilities All National Instruments external controllers such as the AT MXI 1 that are connected to VXI MXI 1 extending controllers have the same basic trigger capabilities Source a single TTL or ECL 0 and 1 only trigger using any protocol on any one of the backplane TTL trigger lines Accept a single backplane TTL or ECL 0 and 1 only trigger using any protocol as long as it does not source SEMI SYNC and AS
119. f programs 2 10 to 2 11 header files 2 9 to 2 10 interrupts and signals 2 17 to 2 19 master memory access 2 14 to 2 16 slave memory access 2 16 to 2 17 system configuration tools 2 11 to 2 12 triggers 2 19 Word Serial communication 2 13 NI VXI functions See also specific groups of functions alphabetical list A 9 to A 14 calling syntax 2 3 classification reference A 1 to A 7 multiple mainframe support 2 5 to 2 8 controllers 2 5 to 2 7 extender and controller parameters 2 7 to 2 8 using NI VXI 2 9 to 2 19 beginning and end of programs 2 10 to 2 11 header files 2 9 to 2 10 interrupts and signals 2 17 to 2 19 master memory access 2 14 to 2 16 slave memory access 2 16 to 2 17 system configuration tools 2 11 to 2 12 triggers 2 19 Word Serial communication 2 13 using with LabWindows CVI 2 4 to 2 5 C C example 2 4 input versus output parameters 2 4 to 2 5 return values and system errors 2 4 to 2 5 type definitions 2 4 VXI only function groups 2 3 VXI VME function groups 2 1 to 2 3 No Cause Given event 3 37 No Cause Given status ID 3 37 O ON OFF trigger protocol 3 52 Owner Privilege 3 28 R Read Protocol Error query 3 6 3 15 Read Ready RR bit 3 6 3 14 ReadMODID function 3 34 register based devices 1 2 Release On Acknowledge ROAK interrupter 3 46 Release On Register Access RORA interrupter 3 46 remote controller 2 5 to 2 6 Index NI VXI User Manual I 6 National Instru
120. formance communication link that interconnects devices using round flexible cables ms Milliseconds Glossary NI VXI User Manual G 10 National Instruments Corporation N NI VXI The National Instruments bus interface software for VME VXIbus systems nonprivileged access One of the defined types of VMEbus data transfers indicated by certain address modifier codes Each of the defined VMEbus address spaces has a defined nonprivileged access mode NULL A special value to denote that the contents usually of a pointer are invalid or zero O octal Numbering system with base 8 using numerals 0 to 7 P parse The act of interpreting a string of data elements as a command to perform a device specific action peek To read the contents pointer A data structure that contains an address or other indication of storage location poke To write a value ppm Parts per million privileged access See Supervisory Access propagation Passing of signal through a computer system protocol Set of rules or conventions governing the exchange of information between computer systems Q query Like command causes a device to take some action but requires a response containing data or other information A command does not require a response Glossary National Instruments Corporation G 11 NI VXI User Manual queue A group of items waiting to be acted upon by the computer The arrangement of the items de
121. g system interaction is handled for you The following section of code gives an example of using an callback handler C C Example define VXI_INT_LEVEL 1 this sample only interested in level 1 NIVXI_HVXIINT is a type defined for VXI VME interrupt callback handlers NIVXI_HVXIINT OldVXIintHandler pointer to save the old handler NIVXI_HVXIINT UserVXIintHandler function declr for new handler main INT16 ret controller Always begin by initializing the NI VXI library ret InitVXIlibrary controller 1 Get address of the old handler OldVXIintHandler GetVXIintHandler VXI_INT_LEVEL Set callback handler to new user defined procedure ret DisableVXIint controller 1 lt lt VXI_INT_LEVEL 1 ret SetVXIintHandler 1 lt lt VXI_INT_LEVEL 1 UserVXIintHandler ret EnableVXIint controller 1 lt lt VXI_INT_LEVEL 1 user code Restore callback handler to what it was before we changed it ret DisableVXIint controller 1 lt lt VXI_INT_LEVEL 1 SetVXIintHandler 1 lt lt VXI_INT_LEVEL 1 OldVXIintHandler ret EnableVXIint controller 1 lt lt VXI_INT_LEVEL 1 Always close the NI VXI library before exiting CloseVXIlibrary The NIVXI_HQUAL and NIVXI_HSPEC should bracket every interrupt handler as shown below NIVXI_HQUAL void NIVXI_HSPEC UserVXIintHandler INT16 controller UINT16 level UINT32 statusID
122. gical address A separate handler can be installed for each VXI logical address present see the description of SetSignalHandler The InitVXIlibrary function automatically installs a default handler DefaultSignalHandler for every VXI logical address If signals are queued the application can use the SignalDeq function to selectively retrieve a signal off a global signal queue by VXI logical address and or type of signal In another method for handling signals and VXI VME interrupts routed to signals other than the two previous methods you can use the function WaitForSignal This function can suspend a process function until a particular signal or one of a set of signals arrives A multitasking operating system lets you have any number of WaitForSignal calls pending A non multitasking operating system permits only one pending WaitForSignal call Notice that even on a multitasking operating system there is only one signal queue for the entire system Therefore if two applications both wait on the same logical address it will be a race condition as to which process will receive the signal Chapter 3 Software Overview NI VXI User Manual 3 38 National Instruments Corporation Programming Considerations The global signal queue used to hold signal values is of a finite length If the application is not handling signals fast enough it is theoretically possible to fill the global signal queue If the global signal queue becomes full
123. gister and responding to a series of Byte Request BREQ Word Serial commands When the data output completes or an error occurs WSSwrt calls its interrupt handler with the status of the call Before responding to the last byte of the write it clears DOR to prevent another BREQ from being sent before the application is able to handle the BREQ properly Chapter 3 Software Overview National Instruments Corporation 3 23 NI VXI User Manual High Level VXI VMEbus Access Functions You can use both low level and high level VXI VMEbus access functions to read or write to VXI VMEbus addresses These are required in many situations including the following Register based device instrument drivers Non VXI VME device instrument drivers Accessing device dependent registers on any type of VXI VME device Implementing shared memory protocols Low level and high level access to the VXI VMEbus as the NI VXI interface defines them are very similar Both sets of functions can perform direct reads of and writes to any VXI VMEbus address space with any privilege state or byte order However the two interfaces have different emphases with respect to user protection error checking and access speed For example your application must check error conditions such as Bus Error BERR separately when using low level accesses High level VXI VMEbus access functions need not take into account any of the considerations that are re
124. gnal Get Status Id VXIintAcknowledgeMode Figure 3 4 NI VXI Interrupt and Signal Model Chapter 3 Software Overview NI VXI User Manual 3 46 National Instruments Corporation ROAK Versus RORA VXI VME Interrupters There are two types of VXI VME interrupters The Release On Acknowledge ROAK interrupter is the more common A ROAK interrupter automatically unasserts the VXI VME interrupt line it is asserting when an interrupt acknowledge cycle on the backplane occurs on the corresponding level The VXIbus specification requires that all message based devices be ROAK interrupters It is recommended that all other types of VXI devices also be ROAK interrupters The Release On Register Access RORA interrupt is the second type of VXI VME interrupter The RORA interrupter continues to assert the VXI VME interrupt line after the interrupt acknowledge cycle is complete The RORA interrupter will unassert the interrupt only when some device specific interaction is performed There is no standard method to cause a RORA interrupter to unassert its interrupt line Because a RORA interrupt remains asserted on the backplane the local CPU interrupt generation must be inhibited until the device dependent acknowledgment is complete The function VXIintAcknowledgeMode specifies whether a VXI VME interrupt level for a particular controller embedded or extended is to be handled as a RORA or ROAK interrupt If the VXI VME interrupt is specified to
125. h its Commander The four basic types of Servant Word Serial functions are as follows Receiving commands Receiving and responding to queries Responding to requests to send buffers Receiving buffers The Word Serial Protocol is a 16 bit transfer protocol between a Commander and its Servants The Commander polls specific bits in the Servant s VXI Response register to determine when it can write a command or read a response from the Data Low register It also determines when a Word Serial protocol error occurs Before a Commander can send a Word Serial command to a Servant it must first poll the Write Ready WR bit until it is asserted set to 1 The Commander can then write the command to the Data Low register If the Commander is sending a query it first sends the query in the same manner as sending a command but then continues by polling the Read Ready RR bit until it is asserted It then reads the response from the Data Low register Chapter 3 Software Overview National Instruments Corporation 3 15 NI VXI User Manual A buffer write is a series of Byte Available Word Serial commands sent to the Servant with the additional constraint that the Data In Ready DIR bit as well as the WR bit must be asserted before sending the Byte Available command The lower 8 bits bits 0 to 7 of the 16 bit command contain a single byte of data bit 8 is the END bit Therefore one Byte Available is sent for each data
126. hat only BERRs occurring via Chapter 3 Software Overview National Instruments Corporation 3 61 NI VXI User Manual low level VXI VMEbus access functions will be reported to this handler See also the descriptions of SetBusErrorHandler and GetBusErrorHandler DefaultSoftResetHandler DefaultSoftResetHandler is the sample handler for the Soft Reset interrupt and is installed as a default handler when InitVXIlibrary initializes the NI VXI software It increments the global variable SoftResetRecv When the Reset bit in the VXI Control register of the local CPU is written the VXI interface if an embedded CPU and the VXI register sets are reset VXI logical address and address base are retained The write to the Reset bit causes an interrupt on the local CPU which can be handled in any appropriate manner The CPU cannot restart operation until the Reset bit is cleared After the Reset bit is cleared the local CPU can go through a reinitialization process or reboot altogether If the local CPU is the Resource Manager and top level Commander the Reset bit should never be written Writing the Reset bit of any device should be reserved for the Commander of the device EnableSoftReset must be called to enable writes to the Reset bit to generate interrupts to the local CPU after the InitVXIlibrary call Note The Soft Reset interrupt does not apply to VME DefaultSysfailHandler controller DefaultSysfailHandler is the sample hand
127. he Commander Word Serial functions give you the necessary capabilities to communicate with a message based Servant device using the Word Serial Longword Serial or Extended Longword Serial protocols These capabilities include the sending of commands and queries and the reading and writing of buffers Servant Word Serial Protocol Functions Servant Word Serial functions allow you to communicate with the message based Commander of the local CPU the device on which the NI VXI interface resides using the Word Serial Longword Serial or Extended Longword Serial protocols These capabilities include command query handling and buffer reads writes VXI Trigger Functions The VXI trigger functions let you source and accept any of the VXIbus trigger protocols The actual capabilities available depend on the specific hardware platform The VXI trigger functions can install handlers for various trigger interrupt conditions Calling Syntax The interface is the same regardless of the development environment or the operating system used Great care has been taken to accommodate all types of operating systems with the same functional interface C C source level compatible whether it is non multitasking for example MS DOS cooperative multitasking such as Microsoft Windows 3 x or Macintosh OS multitasking for example UNIX Wndows 95 or Windows NT or real time such as LynxOS or VxWorks The NI VXI interface includes most of the
128. ial Protocol Appendix A Function Classification Reference NI VXI User Manual A 8 National Instruments Corporation Table A 2 Function Listing by Name Function Group VXI VME C C BASIC DisableACfail System Interrupt Handler DisableSignalInt VXI Signal DisableSoftReset System Interrupt Handler DisableSysfail System Interrupt Handler DisableSysreset System Interrupt Handler DisableTrigSense Triggers DisableVXIint VXI VME Interrupt DisableVXItoSignalInt VXI VME Interrupt EnableACfail System Interrupt Handler EnableSignalInt VXI Signal EnableSoftReset System Interrupt Handler EnableSysfail System Interrupt Handler EnableSysreset System Interrupt Handler EnableTrigSense Triggers EnableVXIint VXI VME Interrupt EnableVXItoSignalInt VXI VME Interrupt FindDevLA System Configuration GenProtError Servant Word Serial Protocol GetACfailHandler System Interrupt Handler GetBusErrorHandler System Interrupt Handler GetByteOrder Low Level VXI VMEbus Access Appendix A Function Classification Reference National Instruments Corporation A 9 NI VXI User Manual Table A 2 Function Listing by Name Function Group VXI VME C C BASIC GetContext Low Level VXI VMEbus Access GetDevInfo System Configuration GetDevInfoLong System Configuration GetDevInfoShort System Configuration GetDevInfoStr System Configuration GetMyLa Local Resource Access
129. ich is installed when the function InitVXIlibrary is called If VXI VME interrupts are enabled via EnableVXIint the VXI VME interrupt handler for a specific logical address is called You must first call RouteVXIint to route VXI VME interrupts to the callback handler as opposed to the signal processing routine Chapter 3 Software Overview NI VXI User Manual 3 48 National Instruments Corporation DefaultVXIintHandler sets the global variables VXIintController VXIintLevel and VXIintStatusId You can leave this default handler installed or install a completely new handler using SetVXIintHandler DisableVXIint controller levels DisableVXIint desensitizes the application to specified VXI interrupt levels being processed as VXI VME interrupts not as VXI signals EnableVXIint enables VXI VME interrupts to be handled as VXI VME interrupts not as VXI signals A 1 negative one or local logical address in the controller parameter specifies the local frame for an embedded CPU or the first extended controller in an external CPU situation DisableVXItoSignalInt controller levels DisableVXItoSignalInt desensitizes the application to specified VXI VME interrupt levels being processed as VXI VME signals An EnableVXItoSignalInt call enables VXI VME interrupt levels that are routed to VXI signals Use DisableVXItoSignalInt to disable these interrupts Use EnableVXIint to enable interrupts not routed to signals A 1 negative o
130. igned integer may also be called a short integer or word INT32 A 32 bit signed integer may also be called a long or longword INT8 An 8 bit signed integer may also be called a char interrupt A means for a device to notify another device that an event occurred interrupt handler A functional module that detects interrupt requests generated by interrupters and performs appropriate actions interrupter A device capable of asserting interrupts and responding to an interrupt acknowledge cycle INTX Interrupt and Timing Extension a daughter card option for MXI mainframe extenders that extends interrupt lines and reset signals on VME boards On VXI boards it also extends trigger lines and the VXIbus CLK10 signal K KB 1 024 or 2 10 kilobyte A thousand bytes L LF Linefeed the ASCII character 0Ah logical address An 8 bit number that uniquely identifies the location of each VXIbus device s configuration registers in a system The A16 register address of a device is C000h Logical Address 40h longword Data type of 32 bit integers Longword Serial A form of Word Serial communication in which Commanders and Protocol Servants communicate with 32 bit data transfers instead of 16 bit data transfers as in the normal Word Serial Protocol low level Programming at the system level with machine dependent commands Glossary National Instruments Corporation G 9 NI VXI User Manual M MB 1 048 576 or
131. ion register and therefore is not applicable to VME devices VXImove srcparms srcaddr destparms destaddr length width VXImove moves a block of bytes words or longwords from a particular address in one of the available address spaces local A16 A24 A32 to any other address in any one of the address spaces The parameters srcparms and destparms specify the address space the privilege access and the byte order used to perform the access for the source address and the destination address respectively The srcaddr and destaddr parameters specify the offset within the particular Chapter 3 Software Overview National Instruments Corporation 3 25 NI VXI User Manual address space for the source and destination respectively The width parameter selects either byte word or longword transfers If one of the addresses selected has no device residing at the address and a bus error occurs VXImove traps the bus error condition and indicates the error through the return status VXIout accessparms address width value VXIout writes a single byte word or longword to a particular VXI VME address in one of the VXI VME address spaces The parameter accessparms specifies the VXI address space the VXI privilege access and the byte order to use with the access The address parameter specifies the offset within the particular VXI VME address space The width parameter selects either byte word or longword transfers If the VXI VME
132. is a user defined type UserLAEntry which is defined in the devinfo h header file For VME devices this information cannot be determined by the VXIbus Resource manager However you can enter this information into the Non VXI Device Editor in VXIedit or VXItedit This will allow you to use these functions to retrieve information about the devices at run time Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 13 NI VXI User Manual Word Serial Communication When communicating with a message based devices MBD in VXI the protocol for string passing is known as Word Serial The term is derived from the fact that all commands are 16 bits in length word length and that strings are sent serially or one byte at a time VXI also accommodates Long Word Serial 32 bit commands and Extended Long Word Serial 48 bit commands However the VXIbus specification revision 1 4 states that only Word Serial commands have been defined Word Serial Protocol is based on a Commander writing 16 bit commands to a Servant register See the Commander Word Serial Protocol Functions in Chapter 3 Software Overview for more information on the protocol The VXIbus specification has defined several commands such as Byte Available Byte Request and Clear The bit patterns for Word Serial commands have been laid out in the VXIbus specification and your application can send these commands to a Servant via the WScmd f
133. ix H handshaking A type of protocol that makes it possible for two devices to synchronize operations hardware context The hardware setting for address space access privilege and byte ordering hex Hexadecimal the numbering system with base 16 using the digits 0 to 9 and letters A to F high level Programming with instructions in a notation more familiar to the user than machine code Each high level statement corresponds to several low level machine code instructions and is machine independent meaning that it is portable across many platforms Hz Hertz a measure of cycles per second I I O Input output the techniques media or devices used to achieve communication between entities IACK Interrupt Acknowledge IEEE Institute of Electrical and Electronics Engineers IEEE 1014 The VME specification Its full title is ANSI IEEE 1014 1987 IEEE Standard for a Versatile Backplane Bus VMEbus IEEE 1155 The VXI specification Its full title is ANSI IEEE 1155 1992 VMEbus Extensions for Instrumentation VXIbus IEEE 488 Standard 488 1978 which defines the GPIB Its full title is IEEE Standard Digital Interface for Programmable Instrumentation Also referred to as IEEE 488 1 since the adoption of IEEE 488 2 Glossary NI VXI User Manual G 8 National Instruments Corporation IEEE 488 2 A supplemental standard for GPIB Its full title is Codes Formats Protocols and Common Commands INT16 A 16 bit s
134. l VXI Commanders monitor the PASSed or FAILed state of their VXI Servants When a VXIbus device is in the FAILed Chapter 3 Software Overview National Instruments Corporation 3 63 NI VXI User Manual state the failed device clears its PASS bit in its Status register and asserts the SYSFAIL signal on the VXIbus backplane DisableSysreset controller DisableSysreset desensitizes the application to Sysreset interrupts from embedded or extended controller s dependent on the hardware platform EnableACfail controller EnableACfail sensitizes the application to ACfail interrupts from embedded controller or extended controller s ACfail conditions dependent on the hardware platform The VXI VMEbus specification allows for a minimum amount of time after a power failure condition occurs for the system to remain operational The detection of the power failure asserts the VXI VMEbus backplane signal ACFAIL An ACfail condition detected on the local CPU generates an interrupt that calls the current ACfail interrupt handler Your application can take any appropriate action within the allotted time period before complete power failure EnableSoftReset EnableSoftReset sensitizes the application to Soft Reset conditions on the local CPU When the Reset bit in the VXI Control register of the local CPU is written the VXI interface if an embedded CPU and the VXI register sets are reset VXI logical address and address base are ret
135. l of the specified type before the process function is suspended If an appropriate signal can be dequeued the signal is Chapter 3 Software Overview NI VXI User Manual 3 40 National Instruments Corporation returned immediately to the caller and the process function is not suspended The following paragraphs describe the VXI signal functions and default handler The descriptions are presented at a functional level describing the operation of each of the functions The functions are grouped by area of functionality DefaultSignalHandler signal DefaultSignalHandler is the sample handler for VXI signals that is installed when the InitVXIlibrary function is called for every applicable VXI logical address The default handler performs no action on the signals except when Unrecognized Command Events are received For these events it calls the function WSabort with an abortop of UnSupCom to abort the current Word Serial transfer in progress DisableSignalInt DisableSignalInt desensitizes the application to local signal interrupts While signal interrupts are disabled a write to the local CPU VXI Signal register does not cause an interrupt on the local CPU instead the local CPU hardware signal FIFO begins to fill up If the hardware FIFO becomes full bus errors will occur on subsequent writes to the Signal register This function is automatically called when the global signal queue becomes full and is automatically re enabled
136. lHandler func SetSysfailHandler replaces the current Sysfail interrupt handler with an alternate handler A Sysfail condition detected on the local CPU generates an interrupt that calls the current Sysfail interrupt handler A default handler DefaultSysfailHandler is automatically installed when InitVXIlibrary initializes the NI VXI software EnableSysfail must be called to enable Sysfail interrupts after the InitVXIlibrary call SetSysresetHandler func SetSysresetHandler replaces the current SYSRESET interrupt handler with an alternate handler The InitVXIlibrary function automatically installs a default handler DefaultSysresetHandler when it initializes the NI VXI software Your application must then call EnableSysreset to enable writes to the Reset bit to generate interrupts to the local CPU Chapter 3 Software Overview National Instruments Corporation 3 67 NI VXI User Manual VXI VMEbus Extender Functions The NI VXI software interface fully supports the standard VXIbus extension method presented in the VXIbus Mainframe Extender Specification When the National Instruments Resource Manager RM completes its configuration all default transparent extensions are complete The transparent extensions include extensions of VXI VME interrupt TTL trigger ECL trigger Sysfail ACfail and Sysreset signals The VXI VMEbus extender functions are used to dynamically change the default RM settings if the application has such a re
137. led whenever the local CPU Commander sends any Longword Serial Protocol command or query While Word Serial operations are enabled the WSSLcmdHandler is called whenever a Longword Serial command is received The WSSLcmdHandler must parse the commands and take the appropriate action Because the VXI specification does not define any Longword Serial commands Chapter 3 Software Overview NI VXI User Manual 3 18 National Instruments Corporation DefaultWSSLcmdHandler calls GenProtError with a protocol error code of UnSupCom for every Longword Serial command received DefaultWSSrdHandler status count DefaultWSSrdHandler is the default handler for the WSSrd interrupt which InitVXIlibrary automatically installs when it initializes the NI VXI software When WSSrd reaches the specified count or an END bit or an error occurs it calls the WSSrd interrupt handler with the status of the call The default handler sets the global variables WSSrdDone WSSrdDoneStatus and WSSrdDoneCount You can use the variable WSSrdDone to poll until the operation is complete Afterwards you can inspect WSSrdDoneStatus and WSSrdDoneCount to see the outcome of the call If you want you can use the SetWSSrdHandler function to install an alternate handler DefaultWSSwrtHandler status count DefaultWSSwrtHandler is the default handler for the WSSwrt interrupt which InitVXIlibrary automatically installs when it initializes the NI VXI software When WSSwrt re
138. ler for the Sysfail interrupt and is installed as a default handler when InitVXIlibrary initializes the NI VXI software The VXIbus specification requires that all VXI Commanders monitor the PASSed or FAILed state of their VXI Servants When a VXIbus device is in the FAILed state the failed device clears its PASS bit in its Status register and asserts the SYSFAIL signal on the VXIbus backplane A Sysfail condition detected on the local CPU generates an interrupt that calls the current Sysfail interrupt handler The failed Servant device must be forced offline or brought back online in an orderly fashion DefaultSysfailHandler scans the local CPU Servants and if a Servant is detected to have failed the Servant s Sysfail Inhibit bit in its Control register is set In addition the global variable SysfailRecv is incremented Chapter 3 Software Overview NI VXI User Manual 3 62 National Instruments Corporation DefaultSysresetHandler controller DefaultSysresetHandler is the sample handler for the Sysreset interrupt and is installed as a default handler when InitVXIlibrary initializes the NI VXI software It increments the global variable SysresetRecv DisableACfail controller DisableACfail desensitizes the application to ACfail interrupts from embedded controller or extended controller s ACfail conditions dependent on the hardware platform The VXI VMEbus specification allows for a minimum amount of time after a power failur
139. ler2 3 55 DisableTrigSense 3 55 EnableTrigSense 3 55 GetTrigHandler 3 56 overview 3 54 SetTrigHandler 3 56 WaitForTrig 3 56 alphabetical list table A 5 capabilities of NI triggering hardware 3 52 to 3 54 embedded external MXI 2 and remote controller trigger 3 54 external controller VXI MXI 1 trigger 3 53 Index National Instruments Corporation I 9 NI VXI User Manual map trigger functions MapTrigToTrig 3 56 to 3 57 overview 3 56 UnMapTrigToTrig 3 57 overview 2 3 3 51 to 3 52 source trigger functions overview 3 57 ScrTrig 3 57 trigger configuration functions overview 3 58 TrigAssertConfig 3 58 TrigCntrConfig 3 58 TrigExtConfig 3 58 to 3 59 TrigTickConfig 3 59 VXI VME function groups 2 1 to 2 3 VXI VMEbus extender functions alphabetical list table A 7 MapECLtrig 3 67 MapTTLtrig 3 67 to 3 68 MapUtilBus 3 68 MapVXIint 3 68 overview 2 2 to 2 3 3 67 VXIbus overview VXI configuration registers figure 1 2 VXI devices 1 1 to 1 2 VXIin function 3 24 VXIinLR function 3 35 VXIinReg function 3 24 VXIintAcknowledgeMode function description 3 50 ROAK versus RORA interrupters 3 46 VXImemAlloc function 3 35 VXImemCopy function 3 35 VXImemFree function 3 35 VXImove function 3 24 to 3 25 VXIout function 3 25 VXIoutLR function 3 36 VXIoutReg function 3 25 VXIpeek function de referencing pointers 3 28 description 3 33 VXIpoke function de referencing pointers 3 28 descripti
140. lloc Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 17 NI VXI User Manual At this point the remote master can perform I O on the shared allocated space In addition the program can use the local address to perform I O on the same space such as reading back a block of data bufaddr malloc 4096 ret VXImemCopy useraddr bufaddr 4096 0 Return memory to local system ret VXImemFree useraddr ret CloseVXIlibrary Interrupts and Signals In NI VXI you can set up your controller to function as both an interrupt handler and an interrupter You can also have your controller respond to writes to its signal register Signaling another device requires the high level or low level VXI VMEbus access functions as discussed earlier In addition NI VXI lets you configure both interrupts and signals to be handled either through callback handlers or through the signal queue See the VXI Signal Functions section in Chapter 3 Software Overview for more details about the signal queue but for now you can look upon it as a FIFO first in first out queue that you can access via the signal queue management functions such as SignalDeq Both the signal queue and the callback handler will provide the status ID obtained from the interrupt acknowledge or from the signal register You can use this value to determine which device generated the interrupt signal
141. lphabetically You can refer to this table if you don t remember the group association of a particular function Both tables use checkmarks to denote whether a VXI function also applies to VME and also whether it is associated with C C and or BASIC About This Manual NI VXI User Manual xiv National Instruments Corporation Appendix B Customer Communication contains forms you can use to request help from National Instruments or to comment on our manuals The Glossary contains an alphabetical list and description of terms used in this manual including abbreviations acronyms and metric prefixes The Index contains an alphabetical list of key terms and topics used in this manual including the page where each one can be found Conventions Used in This Manual The following conventions are used in this manual bold Bold text denotes parameters menus menu items dialog box buttons or options or error messages bold italic Bold italic text denotes a note caution or warning bold Bold text in this font denotes the messages and responses that the monospace computer automatically prints to the screen This font also emphasizes lines of example code that are different from the other examples italic Italic text denotes emphasis a cross reference or an introduction to a key concept monospace Text in this font denotes the names of all VXI function calls source code sections of code function syntax
142. lues on the front of the global signal queue the signal is guaranteed to be the first of its type to be dequeued Note This function is intended only for debugging purposes WaitForSignal la signalmask timeout retsignal retsignalmask WaitForSignal waits for the specified maximum amount of time for a particular signal or class of signals to be received Signalmask defines the type s of signals that the application program waits for The timeout value specifies the maximum amount of time in milliseconds to wait until the signal occurs The signal that unblocks the WaitForSignal call returns in the output parameter retsignal You should use the WaitForSignal function only when signals are queued A multitasking operating system lets you have any number of WaitForSignal calls pending A non multitasking operating system permits only one pending WaitForSignal call Chapter 3 Software Overview National Instruments Corporation 3 43 NI VXI User Manual VXI Interrupt Functions VXI VME interrupts are a basic form of asynchronous communication used by devices with interrupter support In VME a device asserts a VME interrupt line and the VME interrupt handler device acknowledges the interrupt During the VME interrupt acknowledge cycle an 8 bit status ID value is returned Most 680x0 based VME CPUs use this 8 bit value as a local interrupt vector value routed directly to the 680x0 processor This value specifies which interrupt s
143. ly The sourcing device sources a trigger pulse 30 ns TTL 8 ns ECL minimum on the even trigger line TTL0 TTL2 TTL4 TTL6 ECL0 ECL2 or ECL4 and waits for the acknowledge pulse on the next highest odd trigger line TTL1 TTL3 TTL5 TTL7 ECL1 ECL3 or ECL5 The acceptor waits for the source pulse on the even trigger line Sometime after the source pulse is sensed no maximum time is specified the acceptor sends an acknowledge pulse back on the next highest odd trigger line to complete the handshake SEMI SYNC SEMI SYNC is a one line open collector multiple device handshake protocol The sourcing device sources a trigger pulse 50 ns TTL 20 ns ECL minimum on any one of the trigger lines The accepting device s must begin to assert the same trigger line upon reception within 40 ns TTL 15 ns ECL Chapter 3 Software Overview NI VXI User Manual 3 52 National Instruments Corporation maximum time from source assertion edge The accepting device s can later unassert the trigger line no maximum time is specified to complete the handshake START STOP START STOP is a one line multiple device protocol START STOP can be sourced only by the VXI Slot 0 device and sensed by any other devices on the VXI backplane The START STOP protocol is synchronized with the backplane clock CLK10 for TTL CLK100 and SYNC100 for ECL onto any one of the trigger lines A START condition is generated on the assertion edge on th
144. ly if the caller is the last Access Only accessor After a call is made to UnMapVXIAddress the pointer obtained from MapVXIAddress is no longer valid You should no longer use the pointer because a subsequent call may have changed the settings for the particular window or the window may no longer be accessible at all VXIpeek addressptr width value VXIpeek reads a single byte word or longword from a particular address obtained by MapVXIAddress On most platforms using C language interfaces VXIpeek is a macro It is recommended however that you use VXIpeek instead of a direct dereference of the pointer as it supports portability between different platforms and programming languages VXIpoke addressptr width value VXIpoke writes a single byte word or longword to a particular address obtained by MapVXIAddress On most platforms using C language interfaces VXIpoke is a macro It is recommended however that you use VXIpoke instead of a direct dereference of the pointer as it supports portability between different platforms and programming languages Chapter 3 Software Overview NI VXI User Manual 3 34 National Instruments Corporation Local Resource Access Functions Local resources are hardware and or software capabilities that are reserved for the local CPU the CPU on which the NI VXI interface resides You can use these functions to gain access to miscellaneous local resources such as the local CPU register set
145. ments Corporation Request for Service False REQF event 3 37 Request for Service False REQF status ID 3 37 Request for Service True REQT event 3 37 Request for Service True REQT status ID 3 37 Response signals 3 37 Response status IDs 3 43 RespProtError function 3 19 return values and system errors 2 5 ROAK Release On Acknowledge interrupter 3 46 RORA Release On Register Access interrupter 3 46 round robin effect of Commander Word Serial function calls 3 9 RouteSignal function description 3 41 VXI signal handling 3 37 3 44 RouteVXIint function description 3 49 to 3 50 VXI signal handling 3 43 3 44 S ScrTrig function 3 57 SEMI SYNC trigger protocol 3 51 to 3 52 Servant Word Serial communication Extended Longword Serial Protocol 3 15 Longword Serial Protocol 3 15 polling operations 3 14 to 3 15 types of functions 3 14 Word Serial Protocol 3 14 Servant Word Serial Protocol functions alphabetical list table A 2 to A 3 DefaultWSScmdHandler 3 17 DefaultWSSEcmdHandler 3 17 DefaultWSSLcmdHandler 3 17 to 3 18 DefaultWSSrdHandler 3 18 DefaultWSSwrtHandler 3 18 GenProtError 3 18 GetWSScmdHandler 3 18 GetWSSEcmdHandler 3 19 GetWSSLcmdHandler 3 19 GetWSSrdHandler 3 19 GetWSSwrtHandler 3 19 overview 2 3 3 14 to 3 15 programming considerations 3 15 to 3 16 RespProtError 3 19 SetWSScmdHandler 3 19 to 3 20 SetWSSEcmdHandler 3 20 SetWSSLcmdHandler 3 20 SetWSSrdHandler 3 20 SetW
146. ments Corporation Trigger Configuration Functions You can use the NI VXI trigger configuration functions to configure not only the general settings of the trigger inputs and outputs but also the TIC counter and tick timers TrigAssertConfig controller trigline mode TrigAssertConfig configures the local triggering generation method for the TTL ECL triggers You can decide on an individual basis whether to synchronize the triggers to CLK10 You can globally select the synchronization to be the rising or falling edge of CLK10 In addition you can specify the trigger line to partake in automatic external SEMI SYNC acknowledgment In this mode when a trigger is sensed on the line the line is asserted until an external GPIO trigger line which is mapped to the corresponding trigger line is pulsed You can also use AcknowledgeTrig to manually acknowledge a pending SEMI SYNC trigger configured in this fashion TrigCntrConfig controller mode source count TrigCntrConfig configures the TIC chip s 16 bit counter You can use this function to initialize reload or disable the current counter settings If the counter is initialized you must call either SrcTrig or EnableTrigSense to actually start the counter You can use any trigger line CLK10 or EXTCLK as the source of the counter The count range is 1 to 65535 You can use the counter to source multiple sync or multiple semi sync triggers to one or more trigger lines You can also u
147. mming Considerations 3 27 Multiple Pointer Access for a Window 3 28 Owner Privilege 3 28 Access Only Privilege 3 29 GetByteOrder 3 30 GetContext 3 30 GetPrivilege 3 30 GetVXIbusStatus 3 30 GetVXIbusStatusInd 3 31 GetWindowRange 3 31 MapVXIAddress 3 31 MapVXIAddressSize 3 32 SetByteOrder 3 32 SetContext 3 32 Set
148. n be both a Commander and a Servant in a multiple level hierarchy A Commander has exclusive control of its immediate Servants one or more communication and configuration registers Any VXI module has one and only one Commander Commanders use the Word Serial Protocol to communicate with Servants through the Servants communication registers Servants communicate with their Commander responding to the Word Serial commands and queries from their Commander Servants can also communicate asynchronous status and events to their Commander through hardware interrupts or by writing specific messages directly to their Commander s Signal register Interrupts and Asynchronous Events Servants can communicate asynchronous status and events to their Commander through hardware interrupts or by writing specific messages signals directly to their Commander s hardware Signal Chapter 1 Overview of NI VXI National Instruments Corporation 1 5 NI VXI User Manual register Devices that do not have bus master capability always transmit such information via interrupts whereas devices that do have bus master capability can either use interrupts or send signals Some devices can receive only signals some only interrupts while some others can receive both signals and interrupts The VXIbus specification defines Word Serial commands so that a Commander can understand the capabilities of its Servants and configure them to generate interrupts o
149. n the operating system When the original process is resumed the polling will continue The polling will continue Chapter 3 Software Overview NI VXI User Manual 3 10 National Instruments Corporation until the transfer is complete or a timeout occurs This support also keeps a word serial device which is not responding from hanging on the local CPU The following paragraphs describe the Commander Word Serial Longword Serial and Extended Longword Serial Protocol functions The descriptions are grouped by functionality and are presented at a functional level describing the operation of each of the functions WSabort la abortop WSabort aborts the Commander Word Serial operation s in progress with a particular device This function does not perform any Word Serial transfers Instead it aborts any Word Serial operation already in progress The abortop parameter specifies the type of abort to perform The ForcedAbort operation aborts read write and trigger operations with the specified device The UnSupCom operation performs an Unsupported Command abort of the current Word Serial Longword Serial or Extended Longword Serial command in progress The UnSupCom operation is called when an Unrecognized Command Event is received by DefaultSignalHandler WSclr la WSclr sends the Word Serial Clear command to a message based Servant The Clear command clears any pending protocol error on the receiving device The ERR bit is ig
150. ndefinitely long wait for a slave response byte A grouping of adjacent binary digits operated on by the computer as a single unit A byte consists of 8 bits byte order How bytes are arranged within a word or how words are arranged within a longword Motorola ordering stores the most significant byte MSB or word first followed by the least significant byte LSB or word Intel ordering stores the LSB or word first followed by the MSB or word Glossary NI VXI User Manual G 4 National Instruments Corporation C clearing Replacing the information in a register storage location or storage unit with zeros or blanks CLK10 A 10 MHz 100 ppm individually buffered to each module slot differential ECL system clock that is sourced from Slot 0 and distributed to Slots 1 through 12 on P2 It is distributed to each slot as a single source single destination signal with a matched delay of under 8 ns command A directive to a device In VXI three types of commands are as follows In Word Serial Protocol a 16 bit imperative to a servant from its Commander written to the Data Low register In Shared Memory Protocol a 16 bit imperative from a client to a server or vice versa written to the Signal register In Instrument devices an ASCII coded multi byte directive Commander A message based device which is also a bus master and can control one or more Servants communications In message based
151. ne or local logical address in the controller parameter specifies the local frame for an embedded CPU or the first extended controller in an external CPU situation If a RouteVXIint call has specified to route a particular VXI VME interrupt level to the VXI signal processing routine and the global signal queue becomes full DisableVXItoSignalInt is automatically called to inhibit these VXI VME interrupts from being received from the appropriate levels EnableVXItoSignalInt is automatically called to enable interrupt reception when SignalDeq is called EnableVXIint controller levels EnableVXIint sensitizes the application to specified VXI VME interrupt levels being processed as VXI VME interrupts not as VXI signals After calling InitVXIlibrary the application can sensitize itself to interrupt levels for which it is configured to handle RouteVXIint specifies whether interrupts are to be handled as VXI VME interrupts or as VXI signals the default is VXI signals You must then call EnableVXIint to enable interrupts to be handled as VXI VME interrupts not as VXI signals A 1 negative one or local logical address in the controller parameter specifies the local Chapter 3 Software Overview National Instruments Corporation 3 49 NI VXI User Manual frame for an embedded CPU or the first extended controller in an external CPU situation EnableVXItoSignalInt controller levels EnableVXItoSignalInt is used to sensitize th
152. ng the appropriate fields in the VXIedit or VXItedit NI VXI resource editor utility to instruct the controller to respond to bus accesses as a slave What address space is used is dependent on the settings in VXIedit or VXItedit However the actual VXI VMEbus memory addresses are assigned by RESMAN and should be read by the program through the GetDevInfo function Keep in mind that when the controller shares its resources it may not allocate them from the local system first For example if you instruct the system to share 1 MB of RAM the controller will map VXI VME addresses as defined by RESMAN to 1 MB of local memory However the controller may not have prevented the local system from also using this space For example on a IBM compatible PC the first 1 MB of address space contains not only user RAM but also the interrupt vector table video memory BIOS and so on Therefore it is important that you first use VXImemAlloc to reserve a portion of the shared memory and then communicate this address to the remote master that will be accessing the slave memory For example assume that the following code will run on a controller that has shared 1 MB of local RAM C C Example main INT16 ret UINT32 useraddr vxiaddr void bufaddr Initialize and allocate 4 KB of memory ret InitVXIlibrary ret VXImemAlloc 4096 amp useraddr amp vxiaddr Put code here to communicate vxiaddr returned by VXImemA
153. nificant byte word first The application can have either Owner Access Privilege or Access Only Privilege to the applicable window for this function to execute successfully GetContext window context GetContext retrieves all of the hardware interface settings context for a particular VXI VME window The application can have either Owner Access Privilege or Access Only Privilege to the applicable window for this function to execute successfully Any application can use GetContext along with SetContext to save and restore the VXI VME interface hardware state context for a particular window GetPrivilege window priv GetPrivilege retrieves the current windowing hardware VXI VMEbus access privileges for the specified window The possible privileges include Nonprivileged Data Supervisory Data Nonprivileged Program Supervisory Program Nonprivileged Block and Supervisory Block access The application can have either Owner Access Privilege or Access Only Privilege to the applicable window for this function to execute successfully GetVXIbusStatus controller status GetVXIbusStatus retrieves information about the current state of the VXI VMEbus The information that is returned includes the state of the Sysfail ACfail VXI VME interrupt TTL trigger and ECL trigger lines as well as the number of VXI signals on the global signal queue This information returns in a C structure containing all of the known information An individ
154. nored during the transfer The WR bit is polled until asserted after the Clear command is sent to verify that the command executed properly WScmd la cmd respflag response WScmd sends a Word Serial command or query to a message based Servant It polls the WR bit before sending the command and polls the RR bit before reading the response if applicable from the Data Low register WScmd polls the WR bit after either sending the command for a command or reading the response for a query to guarantee that no protocol errors occurred during the transfer Under the VXIbus specification the ERR bit can be asserted at any time prior to reasserting the WR bit Do not use this function to send the Word Serial commands Byte Available BAV Byte Request BREQ Trigger or Clear All of these Word Serial commands require different Response register polling techniques Chapter 3 Software Overview National Instruments Corporation 3 11 NI VXI User Manual WSEcmd la cmdExt cmd respflag response WSEcmd sends an Extended Word Serial command or query to a message based Servant It polls the WR bit before sending the 48 bit command WSEcmd sends the command by writing the Data Extended register first with the upper 16 bits of the command cmdExt followed by the Data High register with the middle 16 bits of the command upper 16 bits of cmd and concluding with the Data Low register with the lower 16 bits of the command lower 16 bits
155. nt Single Tasking Operating System Support The Word Serial Protocol functions have no asynchronous or multiple call support for a non multitasking operating system Because the Word Serial Protocol functions are polled I O functions that do not return to the caller until the entire operation is complete only one call can be pending for the application level code No Word Serial Protocol functions other than WSabort can be called at interrupt service routine time If a Word Serial operation is underway and an interrupt service routine invokes another Word Serial operation the polling mechanism may become inconsistent with the state of the Servant s communication registers This could result in invalid data being transferred protocol errors occurring or a timeout The WSabort function is used to asynchronously abort Word Serial operations in progress and can be used at interrupt service routine time Cooperative Multitasking Support NI VXI supports multiple processes under cooperative multitasking operating systems The behavior is the same as in single tasking operating systems described above Multitasking Support Preemptive Operating System The Word Serial Protocol functions have extensive mutual exclusion support when running on a preemptive multitasking operating system A two level mutual exclusion algorithm is used to allow read write and trigger calls to be made at the same time Command transfers will automatically susp
156. nvironment This chapter concludes with an overview on using the NI VXI application programming interface The NI VXI functions are a set of C C and BASIC language functions you can use to perform operations with a VXI VME system The NI VXI C C language interface is consistent across hardware platforms and operating systems Function Groups The NI VXI functions are divided into several groups All of them apply to VXI but some groups are not applicable to VME VXI VME Function Groups The following NI VXI function groups apply to both VXI and VME System Configuration Functions The system configuration functions provide functionality to initialize the NI VXI software In addition the system configuration functions can retrieve or modify information about devices in your VXI VME system High Level VXIbus Access Functions Similar to the low level VXI VMEbus access functions the high level VXI VMEbus access functions give you direct access to the VXI VMEbus address spaces You can use these functions to read write and move blocks of data between any of the VXI VMEbus address spaces You can specify the main VXI VMEbus privilege mode or byte order The functions trap and report bus errors When the execution speed is not a critical issue the high level VXI VMEbus access functions provide an easy to use interface Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 2 National Instruments Corpor
157. oftware Overview National Instruments Corporation 3 7 NI VXI User Manual In addition to the four basic types of Word Serial transfers there are two special cases the Word Serial Clear and Trigger commands The Word Serial Clear command must ignore the ERR bit One of the functions of the Clear command is to clear a pending protocol error condition If the ERR bit was polled during the transfer the Clear would not succeed The Word Serial Trigger command requires polling the DIR bit as well as the WR bit similar to the buffer write before writing the Trigger to the Data Low register The VXIbus specification requires polling the DIR bit for the Word Serial Trigger to keep the write and trigger model consistent with IEEE 488 2 The Longword Serial and Extended Longword Serial Protocols are similar to the Word Serial Protocol but involve 32 bit and 48 bit command transfers respectively instead of the 16 bit transfers of the Word Serial Protocol The VXIbus specification however provides no common command usages for these protocols The commands are either VXI Reserved or User Defined The NI VXI interface gives you the ability to send any one of these commands Programming Considerations The Commander Word Serial functions provide a flexible easy to use interface Depending upon the hardware and software platforms involved in your system however certain issues need to be taken into account In particular the behavior of these
158. ograms Chapter 2 Introduction to the NI VXI Functions NI VXI User Manual 2 12 National Instruments Corporation For example all VXI devices have at least one logical address by which they can be accessed However it is simple to change the logical address of most devices Therefore any program that uses a constant as a logical address of a particular device can fail if that device is reassigned to a different logical address Programmers can use the NI VXI function FindDevLA to input information about the device such as the manufacturer ID and model code and receive the device s current logical address Consider the case of wanting to locate a device with manufacturer s code ABCh and model number 123h You could use the following code to determine the logical address C C Example main INT16 ret la ret InitVXIlibrary 1 and empty quotes are used for don t cares ret FindDevLA 0xABC 0x123 1 1 1 1 amp la if ret lt 0 printf No such device found n else printf The logical address is d n la ret CloseVXIlibrary In a similar fashion the function GetDevInfo can return a wide assortment of information on a device such as the manufacturer name and number the base and size of A24 32 memory and the protocols that the device supports This information can be returned in either a piecemeal fashion or in one large data structure Notice that this data structure
159. on 3 33 W WaitForSignal function description 3 42 programming considerations 3 39 to 3 40 VXI signal handling 3 37 3 44 WaitForTrig function 3 56 window base register 3 27 windows definition 3 27 Word Serial Clear command 3 7 Word Serial Protocol See also Commander Word Serial communication Commander Word Serial Protocol functions 3 6 overview 1 3 to 1 4 Servant Word Serial Protocol functions 3 14 Word Serial Protocol errors 3 6 3 15 Word Serial Trigger command 3 7 Write Ready WR bit 3 6 3 14 WSabort function description 3 10 interrupt service 3 8 WSclr 3 10 WScmd function 3 10 WSEcmd 3 11 WSgetTmo function 3 11 WSLcmd 3 11 WSLresp function 3 11 to 3 12 WSrd function 3 12 WSrdf function 3 12 WSresp function 3 12 to 3 13 WSSabort function 3 21 WSSdisable function 3 21 WSSenable function 3 21 WSsetTmo function 3 13 Index NI VXI User Manual I 10 National Instruments Corporation WSSLnoResp function 3 21 3 22 WSSLsendResp function 3 21 WSSrd function 3 22 WSSsendResp function 3 22 WSSwrt function 3 22 WStrg function 3 13 WSwrt function 3 13 WSwrtf 3 14
160. on a call to SignalDeq DisableSignalInt along with EnableSignalInt can be used to temporarily suspend the generation of signal interrupts EnableSignalInt EnableSignalInt sensitizes the application to local signal interrupts When signal interrupts are enabled any write to the local CPU VXI Signal register causes an interrupt on the local CPU The internal signal router then routes the signal value to the handler or to the global signal queue as specified by the RouteSignal function EnableSignalInt must be called after InitVXIlibrary to begin the reception of signals Calls to RouteSignal and or SetSignalHandler must be made before the signal interrupt is enabled to guarantee proper signal routing of the first signals Chapter 3 Software Overview National Instruments Corporation 3 41 NI VXI User Manual GetSignalHandler la GetSignalHandler returns the address of the current signal handler for the specified VXI logical address If signal interrupts are enabled via EnableSignalInt the signal handler for a specific logical address is called if the RouteSignal function has been set up to route signals to the handler as opposed to the global signal queue The InitVXIlibrary function automatically installs a default handler DefaultSignalHandler for every VXI logical address RouteSignal la modemask RouteSignal specifies how to route VXI signals for the application Two methods are available to handle VXI signals You c
161. ons to destination trigger locations by using the MapTrigToTrig and UnMapTrigToTrig functions MapTrigToTrig controller srcTrig destTrig mode MapTrigToTrig configures triggering hardware to route specified source trigger locations to destination trigger locations with some possible signal conditioning The possible values for source or destination locations are the TTL trigger lines ECL trigger lines Star X lines Star Y lines or miscellaneous external sources Miscellaneous external sources include front panel trigger ins front panel trigger outs local clocks and crosspoint switch locations The mode parameter specifies how the line is to be routed to the destination You can manipulate the line in various ways including inverting it synchronizing it with the CLK10 or stretching it to a minimum time In this way MapTrigToTrig can be used as a simple map from an external source to a trigger line or as a complex Chapter 3 Software Overview National Instruments Corporation 3 57 NI VXI User Manual crosspoint switch configurator depending on the hardware capabilities of the applicable device UnMapTrigToTrig controller srcTrig destTrig UnMapTrigToTrig unconfigures triggering hardware that was configured by the MapTrigToTrig function to route specified source trigger locations to destination trigger locations Source Trigger Functions The NI VXI source trigger functions act as a standard interface for asserting
162. or from the local user s address space into the local shared memory region On some interfaces your application cannot directly access local shared memory VXImemCopy gives you fast access to this local shared memory VXImemFree useraddr VXImemFree reallocates physical RAM from the operating system s dynamic memory pool allocated using VXImemAlloc VXImemAlloc returns not only the user address that the application uses but also the VXI address that a remote device would use to access this RAM When the application is through using the memory it should make a call to VXImemFree with the user address to return the memory to the operating system s dynamic memory pool Chapter 3 Software Overview NI VXI User Manual 3 36 National Instruments Corporation VXIoutLR reg width value VXIoutLR writes a single byte word or longword to the local CPU VXI VME registers On many CPUs the local CPU VXI VME registers cannot be accessed from the local CPU in the A16 address space window due to hardware limitations Another area in the local CPU address space is reserved for accessing the local CPU VXI registers VXIoutLR is designed to write to these local VXI VME registers The VXI VME access privilege is not applicable but can be assumed to be Nonprivileged Data The byte order is Motorola Unless otherwise specified writes should always be performed as words This function can be used to write application specific registers A24
163. part without the prior written consent of National Instruments Corporation Trademarks LabVIEW NI 488 2 NI VISA NI VXI and VXIpc are trademarks of National Instruments Corporation Product and company names listed are trademarks or trade names of their respective companies WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS National Instruments products are not designed with components and testing intended to ensure a level of reliability suitable for use in treatment and diagnosis of humans Applications of National Instruments products involving medical or clinical treatment can create a potential for accidental injury caused by product failure or by errors on the part of the user or application designer Any use or application of National Instruments products for or involving medical or clinical treatment must be performed by properly trained and qualified medical personnel and all traditional medical safeguards equipment and procedures that are appropriate in the particular situation to prevent serious injury or death should always continue to be used when National Instruments products are being used National Instruments products are NOT intended to be a substitute for any form of established process procedure or equipment used to monitor or safeguard human health and safety in medical or clinical treatment National Instruments Corporation v NI VXI User Manual Table of Contents About
164. pointer register A32 pointer register and so on for the local CPU VXI Signal Functions With these functions VXI VME bus master devices can interrupt another device VXI signal functions can specify the signal routing manipulate the global signal queue and wait for a particular signal value or set of values to be received VXI signals are a basic form of asynchronous communication used by VXI VME bus master devices A VXI signal is a 16 bit value written to the Signal register of a VXI message based device Normally the write to the Signal register generates a local CPU interrupt and the local CPU then acquires the signal value in some device specific manner All National Instruments hardware platforms have a hardware FIFO to accumulate signal values while waiting for the local CPU to retrieve them The format of the 16 bit signal value is defined by the VXIbus specification and is the same as the format used for the VXI interrupt status ID word that is returned during a VXI interrupt acknowledge cycle All VXI signals and status ID values contain the VXI logical address of the sending device in the lower 8 bits of the VXI signal or status ID value The upper 8 bits of the 16 bit value depends on the VXI device type Note For VME bus master devices the VXI signal register can be considered a general purpose notification register Although the VXIbus specification defines the use for this register you can program the application on
165. quired by the low level VXIbus access functions The high level VXI VMEbus access functions have all necessary information for accessing a particular VXI VMEbus address wholly contained within the function parameters The parameters prescribe the address space privilege state byte order and offset within the address space High level VXI VMEbus access functions automatically trap bus errors and return an appropriate error status Using the high level VXI VMEbus access functions involves more overhead but if overall throughput of a particular access for example configuration or small number of accesses is not the primary concern the high level VXI VMEbus access functions act as an easy to use interface for VXI VMEbus accesses Programming Considerations All accesses to the VXI VMEbus address spaces performed by use of the high level VXI VMEbus access functions are fully protected The hardware interface settings context for the applicable window are saved on entry to the function and restored upon exit No other functions in the NI VXI interface including the low level VXI VMEbus access functions will conflict with the high level Chapter 3 Software Overview NI VXI User Manual 3 24 National Instruments Corporation VXI VMEbus access functions You can use both high level and low level VXI VMEbus access functions at the same time The following paragraphs describe the high level VXI VMEbus access functions VXIin accessparm
166. quirement Usually the application never needs to change the default settings Consult your utilities manual on how to use the NI VXI resource editor utility either VXIedit or VXItedit to change the default extender settings Note The MXIbus which is used as the transparent mainframe extender bus extends both VXI and VME chassis and even allows a system consisting of both VXI and VME chassis The following paragraphs describe the VXI VMEbus extender functions The descriptions are presented at a functional level describing the operation of each of the functions MapECLtrig MapECLtrig configures mainframe extender triggering hardware to map the specified ECL triggers for the specified mainframe in the specified direction into or out of the mainframe If the specified frame extender can extend VXI ECL triggers between the mainframes you can use MapECLtrig to configure the mainframe to mainframe mapping The NI VXI Resource Manager automatically configures a default mapping based on the user modifiable configuration files The MapECLtrig function can dynamically reconfigure the ECL trigger mapping Only special circumstances should require any changes to the default configuration MapTTLtrig MapTTLtrig configures mainframe extender triggering hardware to map the specified TTL triggers for the specified mainframe in the specified direction into or out of the mainframe If the specified frame extender can extend VXI TTL triggers bet
167. r RM table information into data structures at startup so that you can find device names or logical addresses by specifying certain attributes of the device for identification purposes Initializing and closing the NI VXI software interface and getting information about devices in the system are among the most important aspects of the NI VXI software All applications need to use the system configuration functions at one level or another When the NI VXI RM runs it logs the system configuration information in the RM table file resman tbl The InitVXIlibrary function reads the information from resman tbl into data structures accessible from the GetDevInfo and SetDevInfo functions From this point on you can retrieve any device related information from the entry in the table In most cases you do not need to modify resource manager information However you can use SetDevInfo functions to modify the information in the table In this manner both the application and the driver functions have direct access to all the necessary VXI VME system information Your application must call the CloseVXIlibrary function upon exit to free all data structures and disable interrupts The following paragraphs describe the system configuration functions The descriptions are presented at a functional level describing the operation of each function Chapter 3 Software Overview NI VXI User Manual 3 2 National Instruments Corporation CloseVXIlibrary
168. r signals in a particular way For example a Commander can instruct its Servants to use a particular interrupt line to send signals rather than generate interrupts or configure the reporting of only certain status or error conditions Although the Word Serial Protocol is reserved for Commander Servant communications you can establish peer to peer communication between two VXI VME devices through a specified shared memory protocol or simply by writing specific messages directly to the device s Signal register in addition to the VXI VME interrupt lines MXIbus Overview The MXIbus is a high performance communication link that interconnects devices with a cabled communication link for very high speed communication between physically separate devices The emergence of the VXIbus inspired MXI National Instruments a member of the VXIbus Consortium and the VITA organization recognized that VXI requires a new generation of connectivity for the instrumentation systems Additionally National Instruments realized that the same technology could be used also for the VMEbus which is the foundation technology under VXI National Instruments developed the MXIbus specification over a period of two years and announced it in April 1989 as an open industry standard MXI 2 Overview MXI 2 is the second generation of the National Instruments MXIbus product line The MXIbus is a general purpose 32 bit multimaster system bus on a cable MXI 2 expands the
169. rd call is pending or BREQ if a WSSwrt call is pending DefaultWSScmdHandler parses the commands and takes appropriate action If it is a query it returns a response using the WSSsendResp function If it is a command it calls the WSSnoResp function to acknowledge it If either a BREQ or BAV command is received via this handler it calls GenProtError with the corresponding protocol error code DOR violation or DIR violation For unsupported commands the protocol error code sent to GenProtError is UnSupCom DefaultWSSEcmdHandler cmdExt cmd DefaultWSSEcmdHandler is the default handler for the WSSwrt interrupt which InitVXIlibrary automatically installs when it initializes the NI VXI software The current WSSEcmdHandler is called whenever the local CPU Commander sends any Extended Longword Serial Protocol command or query While Word Serial operations are enabled the WSSEcmdHandler is called whenever a Longword Serial command is received WSSEcmdHandler must parse the commands and take the appropriate action Because the VXI specification does not define any Extended Longword Serial commands DefaultWSSEcmdHandler calls GenProtError with a protocol error code of UnSupCom for every Extended Longword Serial command received DefaultWSSLcmdHandler cmd DefaultWSSLcmdHandler is the default handler for the WSSwrt interrupt which InitVXIlibrary automatically installs when it initializes the NI VXI software The current WSSLcmdHandler is cal
170. rrupt status ID has the same format as the VXI signal your application can handle VXI interrupts as VXI signals However because VME interrupters may be present in a VXI system the VXI VME interrupt handler functions are included with the NI VXI software The RouteVXIint function specifies whether the status ID value should be handled as a signal or handled by a VXI VME interrupt handler Two methods are available to handle VXI signals Signals can be handled either by calling a signal handler or by queueing on a global signal queue The RouteSignal function Chapter 3 Software Overview NI VXI User Manual 3 44 National Instruments Corporation specifies which types of signals are handled by signal handlers and which are queued onto the global signal queue for each VXI logical address A separate handler can be installed for each VXI logical address present refer to the description for SetSignalHandler A default handler DefaultSignalHandler is automatically installed when InitVXIlibrary is called from the application for every VXI logical address If signals are queued the application can use the SignalDeq function to selectively return a signal off a global signal queue by VXI logical address and or type of signal Another method for handling signals and VXI VME interrupts routed to signals can be used instead of the two previous methods and involves using the WaitForSignal function WaitForSignal can be used to suspend a proces
171. s address width value VXIin reads a single byte word or longword from a particular VXI VME address in one of the VXI address spaces The parameter accessparms specifies the VXI VME address space the VXI privilege access and the byte order to use with the access The address parameter specifies the offset within the particular VXI VME address space The width parameter selects either byte word or longword transfers The value read from the VXI VMEbus returns in the output parameter value If the VXI VME address selected has no device residing at the address and a bus error occurs VXIin traps the bus error condition and indicates the error through the return status VXIinReg la reg value VXIinReg reads a single 16 bit value from a particular VXI device s VXI registers within the logical address space the upper 16 KB of VXI A16 address space The function sets the VXI access privilege to Nonprivileged Data and the byte order to Motorola If the VXI address selected has no device residing at the address and a bus error occurs VXIinReg traps the bus error condition and indicates the error through the return status This function is mainly for convenience and is a layer on top of VXIinLR and VXIin If the la specified is the local CPU logical address it calls the VXIinLR function Otherwise it calculates the A16 address of the VXI device s register and calls VXIin Note VXIinReg is designed to access a VXIbus device configurat
172. s function until a particular signal or one of a set of signals arrives In a multitasking operating system any number of WaitForSignal calls can be pending In a nonmultitasking operating system only one WaitForSignal call can be pending If the RouteVXIint has specified that a status ID value should be handled by the VXI VME interrupt handler and not by the signal handler the specified callback handler is invoked The VXI VME interrupt handler for a particular level is called with the VXI interrupt level and the status ID without any interpretation of the status ID value The callback handler can do whatever is necessary with the status ID value The SetVXIintHandler function can be called to change the current callback handler for a particular level A default handler DefaultVXIintHandler is automatically installed with a call to InitVXIlibrary at the start of the application EnableVXIint and DisableVXIint are used to sensitize and desensitize the application to VXI VME interrupts routed to the VXI VME interrupt handlers EnableVXItoSignalInt and DisableVXItoSignalInt are used to sensitize and desensitize the application to VXI VME interrupts routed to be processed as VXI signals When you are testing VXI VME interrupt handlers or creating a message based interrupter you must assert a VXI VMEbus interrupt line and present a valid status ID value The AssertVXIint function asserts an interrupt on the local CPU or on the specified extended
173. s should occur only when the local CPU is not the Resource Manager or VME devices not listed in the Non VXI Device Editor in VXIedit Support is not provided to handle these signals via the global signal queue or the WaitForSignal function Chapter 3 Software Overview NI VXI User Manual 3 42 National Instruments Corporation SignalDeq la signalmask signal SignalDeq retrieves signals from the global signal queue Two methods are available to handle VXI signals You can handle the signals either by handlers or by queueing on a global signal queue The RouteSignal function specifies which types of signals should be handled by which of the two methods for each VXI logical address You can use SignalDeq to selectively dequeue a signal off of the global signal queue The signal specified by signalmask for the specified logical address la is dequeued and returned in the output parameter signal SignalEnq signal SignalEnq places signals at the end of the global signal queue You can use SignalEnq within a signal handler to queue a signal or to simulate the reception of a signal by placing a value on the global signal queue that was not actually received as a signal SignalJam signal SignalJam places signals at the front of the global signal queue SignalJam can be used to simulate the reception of a signal by placing a value on the global signal queue that was not actually received as a signal Because SignalJam places signal va
174. se it to accept multiple sync or multiple semi sync triggers from one trigger line The counter has two outputs TCNTR and GCNTR The TCNTR signal pulses for 100 ns every time a source pulse occurs You can use MapTrigToTrig to map the TCNTR signal to one or more trigger lines The GCNTR signal stays unasserted until the counter goes from 1 to 0 It then becomes asserted until the counter is disabled You can use the MapTrigToTrig function to directly map the GCNTR signal to one or more GPIO lines TrigExtConfig controller extline mode TrigExtConfig configures the way the external trigger sources General Purpose Inputs and Outputs or GPIOs are configured The TIC chip has 10 GPIO lines Typically GPIO 0 is connected to the front panel In connector GPIO 1 is connected to the front panel Out connector GPIO 2 is connected to a direct ECL bypass from the front Chapter 3 Software Overview National Instruments Corporation 3 59 NI VXI User Manual panel GPIO 3 is fed back in as the EXTCLK signal used for signal conditioning modes with MapTrigToTrig The six remaining GPIOs are dependent upon the hardware platform Regardless of the sources connected to the GPIOs TrigExtConfig configures several aspects of the connection You can disconnect and feed back the connection for use as a crosspoint switch You can also choose whether to invert the external input In addition you can configure the GPIO to be asserted high or low continuously
175. signal sent to the Commander The rsv bit should be automatically deasserted when the Word Serial Read Status Byte query is sent S s Seconds SEMI SYNC Protocol A one line open collector multiple device handshake trigger protocol Servant A device controlled by a Commander setting To place a binary cell into the 1 non zero state Shared Memory Protocol A communications protocol for message based devices that uses a block of memory that is accessible to both a client and a server The memory block acts as the medium for the protocol transmission short integer Data type of 16 bits same as word Glossary National Instruments Corporation G 13 NI VXI User Manual signal Any communication between message based devices consisting of a write to a Signal register Sending a signal requires that the sending device have VMEbus master capability signed integer n bit pattern interpreted such that the range is from 2 n 1 to 2 n 1 1 slave A functional part of a MXI VME VXIbus device that detects data transfer cycles initiated by a VMEbus master and responds to the transfers when the address specifies one of the device s registers SMP See Shared Memory Protocol SRQ Service Request status ID A value returned during an IACK cycle In VME usually an 8 bit value which is either a status data value or a vector ID value used by the processor to determine the source In VXI a 16 bit value used as a data th
176. software are warranted not to fail to execute programming instructions due to defects in materials and workmanship for a period of 90 days from date of shipment as evidenced by receipts or other documentation National Instruments will at its option repair or replace software media that do not execute programming instructions if National Instruments receives notice of such defects during the warranty period National Instruments does not warrant that the operation of the software shall be uninterrupted or error free A Return Material Authorization RMA number must be obtained from the factory and clearly marked on the outside of the package before any equipment will be accepted for warranty work National Instruments will pay the shipping costs of returning to the owner parts which are covered by warranty National Instruments believes that the information in this manual is accurate The document has been carefully reviewed for technical accuracy In the event that technical or typographical errors exist National Instruments reserves the right to make changes to subsequent editions of this document without prior notice to holders of this edition The reader should consult National Instruments if errors are suspected In no event shall National Instruments be liable for any damages arising out of or related to this document or the information contained in it EXCEPT AS SPECIFIED HEREIN NATIONAL INSTRUMENTS MAKES NO WARRANTIES EXPRESS OR IMPLIED AND SPE
177. source code as an example and is automatically installed when InitVXIlibrary is called The Chapter 3 Software Overview NI VXI User Manual 3 20 National Instruments Corporation default handler provides examples of how to parse commands respond to queries and generate protocol errors SetWSSEcmdHandler func SetWSSEcmdHandler replaces the current WSSEcmd interrupt handler with an alternate handler While Word Serial operations are enabled the WSSEcmd interrupt handler is called whenever an Extended Longword Serial command is received A default handler DefaultWSSEcmdHandler is supplied in source code as an example and is automatically installed when InitVXIlibrary is called SetWSSLcmdHandler func SetWSSLcmdHandler replaces the current WSSLcmd interrupt handler with an alternate handler While Word Serial operations are enabled the WSSLcmd interrupt handler is called whenever a Longword Serial command is received A default handler DefaultWSSLcmdHandler is supplied in source code as an example and is automatically installed when InitVXIlibrary initializes the NI VXI software SetWSSrdHandler func SetWSSrdHandler replaces the current WSSrd interrupt handler with an alternate handler When WSSrd reaches the specified count or an END bit or an error occurs it calls the WSSrd interrupt handler with the status of the call A default handler DefaultWSSrdHandler is automatically installed when InitVXIlibrary is calle
178. space Valid numbers for n are 16 24 and 32 address window A range of address space that can be accessed from the application program ANSI American National Standards Institute ASCII American Standard Code for Information Interchange A 7 bit standard code adopted to facilitate the interchange of data among various types of data processing and data communications equipment ASIC Application Specific Integrated Circuit a custom chip asserted A signal in its active true state asynchronous Not synchronized not controlled by periodic time signals and therefore unpredictable with regard to the timing of execution of commands ASYNC Protocol A two device two line handshake trigger protocol using two consecutive even odd trigger lines a source acceptor line and an acknowledge line B backplane An assembly typically a PCB with 96 pin connectors and signal paths that bus the connector pins A C size VXIbus system will have two sets of bused connectors called the J1 and J2 backplanes A D size VXIbus system will have three sets of bused connectors called the J1 J2 and J3 backplane base address A specified address that is combined with a relative address or offset to determine the absolute address of a data location All VXI address windows have an associated base address for their assigned VXI address spaces Glossary National Instruments Corporation G 3 NI VXI User Manual BAV Word Serial Byte Availa
179. tVXIlibrary calls When CloseVXIlibrary returns a successful code it also returns either a zero or a one A zero indicates that the structure has been successfully destroyed and a one indicates that there are still outstanding calls to InitVXIlibrary that must be closed before the structure is destroyed The outcome of all of this is that when exiting a program you should call CloseVXIlibrary the same number of times that you have called InitVXIlibrary Caution In environments where all applications share NI VXI and hence the internal structure such as Microsoft Windows it can be dangerous for any one application to call CloseVXIlibrary until it returns zero because this can close out the structure from under another application It is vital to keep track of the number of times you have called InitVXIlibrary System Configuration Tools The System Configuration Functions section of Chapter 3 Software Overview describes functions that a program can use to access information about the system This is obtained either through configuration information or from information obtained by RESMAN Armed with these functions a program can be more flexible to changes within the system Note The examples in this manual do not check for either warnings or errors in most of the functions return codes This step is omitted only to simplify the example programs We strongly recommend that you include error checking in your own pr
180. termines their processing priority Queues are usually accessed in a FIFO fashion R read To get information from any input device or file storage media register A high speed device used in a CPU for temporary storage of small amounts of data or intermediate results during processing register based device A Servant only device that supports only the four basic VXIbus configuration registers Register based devices are typically controlled by message based devices via device dependent register reads and writes remote controller A device in the VXI system that has the capability to control the VXIbus but has no intelligent CPU installed An example is the VXI MXI 2 REQF Request False a VXI Event condition transferred using either VXI signals or VXI interrupts indicating that a Servant no longer has a need for service REQT Request True a VXI Event condition transferred using either VXI signals or VXI interrupts indicating that a Servant has a need for service resman The name of the National Instruments Resource Manager application in the NI VXI bus interface software See Resource Manager Resource Manager A message based Commander located at Logical Address 0 which provides configuration management services such as address map configuration Commander and Servant mappings and self test and diagnostic management Response signal Used to report changes in Word Serial communication status between a Servant and its
181. the controller to respond to write to this register in any manner you require Chapter 3 Software Overview National Instruments Corporation 3 37 NI VXI User Manual VXI signals from message based devices can be one of two types Response signals and Event signals bit 15 distinguishes between the two Response signals are used to report changes in Word Serial communication status between a Servant and its Commander Event signals are used to inform another device of other asynchronous changes The four Event signals currently defined by the VXIbus specification other than Shared Memory Events are No Cause Given Request for Service True REQT Request for Service False REQF and Unrecognized Command REQT and REQF are used to manipulate the SRQ condition RSV bit assertion in the IEEE 488 488 2 status byte while Unrecognized Command is used to report unsupported Word Serial commands only in VXIbus specification Revision 1 2 If the sender of a signal or VXI interrupt status ID value is a register based device the upper 8 bits are device dependent Consult your device manual for definitions of these values Two methods are available to handle VXI signals under the NI VXI software interface Signals can be handled either by calling a handler or by queuing on a global signal queue The RouteSignal function specifies which types of signals are handled by the handlers and which are queued onto the global signal queue for each VXI lo
182. tion InitVXIlibrary InitVXIlibrary is the NI VXI initialization routine An application must call InitVXIlibrary at application startup InitVXIlibrary performs all necessary installation and initialization procedures to make the NI VXI interface functional This includes copying all of the RM device information into the data structures in the NI VXI library This function configures all hardware interrupt sources but leaves them disabled and installs the corresponding default handlers It also creates and initializes any other data structures required internally by the NI VXI interface When your application completes or is aborted it must call CloseVXIlibrary to free data structures and disable all of the interrupt sources SetDevInfo la field fieldvalue SetDevInfo changes information about the specified device in the NI VXI RM table The field parameter specifies the attribute of the information to change Possible fields include the device name Commander s logical address mainframe number slot manufacturer ID number manufacturer name model code model name device class VXI address space base size allocated VXI interrupt lines handlers allocated protocols supported and so on A field value of zero 0 specifies to change the specified entry with the supplied structure containing all possible information about the specified device You should use this function only in very special situations because it updates inform
183. tion forms for you to complete These forms are in Appendix B Customer Communication at the end of this manual National Instruments Corporation 1 1 NI VXI User Manual Overview of NI VXI Chapter 1 This chapter introduces you to the concepts of VXI VME eXtensions for Instrumentation VME MXI Multisystem eXtension Interface and their relationship to the NI VXI application programmer s interface API Comprehensive functions for programming the VXIbus VMEbus are included with the NI VXI software They are available for a variety of controller platforms and operating systems Among the compatible platforms are the National Instruments line of embedded controllers and external computers that have a MXIbus interface Note The following chapter discusses features unique to VXI as well as common VXI VME features VME users can skip to the section entitled Interrupts and Asynchronous Events VXIbus Overview Concepts of the VXIbus specification include the VXI device message based devices the World Serial Protocol the Commander Servant hierarchy and hardware interrupts and asynchronous events VXI Devices A VXI device has a unique logical address which serves as a means of referencing the device in the VXI system This logical address is analogous to a GPIB device address VXI uses an 8 bit logical address allowing for up to 256 VXI devices in a VXI system Each VXI device must have a specific set of registers c
184. to the signal processing routine A default handler DefaultVXIintHandler is automatically installed for every applicable VXI interrupt level when the InitVXIlibrary function is called RouteVXIint controller Sroute RouteVXIint specifies whether status ID values returned from a VXI VME interrupt acknowledge cycle are routed to a VXI VME interrupt handler or to the VXI signal processing routine The function RouteVXIint specifies whether the status ID value should be handled as a signal or handled locally by a VXI VME interrupt handler Two methods are available to handle VXI signals Signals can be handled either by signal handlers as signals or by queueing on a global signal Chapter 3 Software Overview NI VXI User Manual 3 50 National Instruments Corporation queue The RouteSignal function specifies which types of signals should be handled by signal handlers and which should be queued on the global signal queue for each VXI logical address If the VXI VME interrupt status IDs are specified to be handled by a VXI VME interrupt handler the level and status ID value is sent to the appropriate callback handler when an interrupt occurs An individual handler can be installed for each of the seven VXI VME interrupt levels EnableVXIint and EnableVXItoSignalInt must be used to sensitize the local CPU to interrupts generated by VXI VME interrupts Only the levels routed to the appropriate handlers VXI VME interrupts or VXI signals vi
185. tocol WSwrt WSwrti WSwrtl Commander Word Serial Protocol WSwrtf Commander Word Serial Protocol National Instruments Corporation B 1 NI VXI User Manual Customer Communication B Appendix For your convenience this appendix contains forms to help you gather the information necessary to help us solve technical problems you might have as well as a form you can use to comment on the product documentation Filling out a copy of the Technical Support Form before contacting National Instruments helps us help you better and faster National Instruments provides comprehensive technical assistance around the world In the U S and Canada applications engineers are available Monday through Friday from 8 00 a m to 6 00 p m central time In other countries contact the nearest branch office You may fax questions to us at any time Electronic Services Bulletin Board Support National Instruments has BBS and FTP sites dedicated for 24 hour support with a collection of files and documents to answer most common customer questions From these sites you can also download the latest instrument drivers updates and example programs For recorded instructions on how to use the bulletin board and FTP services and for BBS automated information call 512 795 6990 You can access these services at United States 512 794 5422 or 800 327 3077 Up to 14 400 baud 8 data bits 1 stop bit no parity United Kingdom 01635 551422 Up to
186. troller connected to other frames figure 2 6 embeddded controller connected using MXI 2 figure 2 7 F fax and telephone support B 2 FaxBack support B 2 FindDevLA function 3 2 FTP support B 1 functions See NI VXI functions specific groups of functions G GenProtError function 3 18 GetACfailHandler function 3 64 GetBusErrorHandler function 3 64 GetByteOrder function 3 30 GetContext function 3 30 GetDevInfo function 3 3 GetDevInfoLong function 3 3 GetDevInfoShort function 3 3 GetDevInfoStr function 3 3 GetMyLA function 3 34 GetPrivilege function 3 30 GetSignalHandler function 3 41 GetSoftResetHandler function 3 65 GetSysfailHandler function 3 65 GetSysresetHandler function 3 65 GetTrigHandler function 3 56 GetVXIbusStatus function 3 30 GetVXIbusStatusInd function 3 31 GetVXIintHandler function 3 49 GetWindowRange function 3 31 GetWSScmdHandler function 3 18 GetWSSEcmdHandler function 3 19 GetWSSLcmdHandler function 3 19 GetWSSrdHandler function 3 19 GetWSSwrtHandler function 3 19 global signal queue 3 38 H hardware context high level VXI VMEbus access functions 3 23 low level VXI VMEbus access functions 3 27 header files 2 9 to 2 10 busacc h file 2 10 datasize h file 2 9 devinfo h file 2 10 high level VXI VMEbus access functions alphabetical list table A 3 overview 2 1 3 23 programming considerations 3 23 to 3 24 VXIin 3 24 VXIinReg 3 24 VXImove 3 24 to 3 25 VXIout
187. types of access privileges to a window are available to aid in solving this problem Owner Privilege and Access Only Privilege These two privileges define which caller of the MapVXIAddress function can change the settings of the corresponding window Owner Privilege A caller can obtain Owner Privilege to a window by requesting owner privilege in the MapVXIAddress call via the accessparms parameter This call will not succeed if another process already has either Owner Privilege or Access Only Privilege to that window If the call succeeds the function returns a valid pointer and a non negative return value The 32 bit windowId output parameter returned from the MapVXIAddress call associates the C pointer returned from the function with a particular window and also signifies Owner Privilege to that window Owner Privilege access is complete and exclusive The caller can use SetPrivilege SetByteOrder and SetContext with this windowId to dynamically change the access privileges Notice that if the call to MapVXIAddress succeeds for either Owner Privilege or Access Only Privilege the pointer remains valid in both cases until an explicit UnMapVXIAddress call is made for the corresponding window The pointer is guaranteed to be a valid pointer in either multitasking systems or nonmultitasking systems The advantage with Owner Privilege is that it gives complete and exclusive access for that window to the caller so you can dynamically change the
188. ual hardware platform might not support all of the different hardware signals polled In this case a value of 1 is returned for the corresponding field in the structure Interrupt service routines can automatically handle all of the conditions retrieved from this function if enabled to do so You can use this function for simple polled operations Chapter 3 Software Overview National Instruments Corporation 3 31 NI VXI User Manual GetVXIbusStatusInd controller field status GetVXIbusStatusInd retrieves information about the current state of the VXI VMEbus The information that can be returned includes the state of the Sysfail ACfail VXI interrupt TTL trigger or ECL trigger lines as well as the number of VXI signals on the global signal queue The specified information returns in a single integer value The field parameter specifies the particular VXI VMEbus information to be returned An individual hardware platform might not support the specified hardware signals polled In this case a value of 1 is returned in status Interrupt service routines can automatically handle all of the conditions retrieved from this function if enabled to do so You can use this function for simple polled operations GetWindowRange window windowbase windowend GetWindowRange retrieves the range of addresses that a particular VXI VMEbus window can currently access within a particular VXI VMEbus address space The windowbase and windowend o
189. ugh the use of callback routines The NI VXI software handles all system interrupt handlers in the same manner Each type of interrupt has its own specified default handler which is installed when InitVXIlibrary initializes the NI VXI software If your application program requires a different interrupt handling algorithm it can call the appropriate SetHandler function to install a new callback handler All system interrupt handlers are initially disabled except for Bus Error The corresponding enable function for each handler must be called in order to invoke the default or user installed handler Chapter 3 Software Overview NI VXI User Manual 3 60 National Instruments Corporation The following paragraphs describe the system interrupt handler functions and default handlers The descriptions are presented at a functional level describing the operation of each of the functions The functions are grouped by area of functionality AssertSysreset controller mode AssertSysreset asserts the SYSRESET signal on the specified controller You can use this function to reset the local CPU individual mainframes all mainframes or the entire system If you reset the system but not the local CPU you will need to re execute all device configuration programs Note Due to the operation of some operating systems not all platforms support resetting the local CPU DefaultACfailHandler controller DefaultACfailHandler is the sample handler
190. ular window As a result the application can set the hardware context associated with a particular pointer into VXI VME address spaces obtained from MapVXIAddress After making a MapVXIAddress call for Owner Access to a particular window and possibly calls to SetPrivilege and SetByteOrder you can call GetContext to save this context for later restoration by SetContext Chapter 3 Software Overview National Instruments Corporation 3 33 NI VXI User Manual SetPrivilege window priv SetPrivilege sets the VXI VMEbus windowing hardware to access the specified window with the specified VXI VMEbus access privilege The possible privileges include Nonprivileged Data Supervisory Data Nonprivileged Program Supervisory Program Nonprivileged Block and Supervisory Block access The application must have Owner Access Privilege to the applicable window for this function to execute successfully Notice that some platforms may not support all of the privilege states This is reflected in the return code of the call to SetPrivilege Nonprivileged Data transfers must be supported within the VXI VME environment and are supported on all hardware platforms UnMapVXIAddress window UnMapVXIAddress reallocates the window mapped using the MapVXIAddress function If the caller is an Owner Privilege accessor only one is permitted the window is free to be remapped If the caller is an Access Only Privilege accessor the window can be remapped on
191. um level of capability are called register based devices With this common set of configuration registers the centralized Resource Manager RM a software module can perform automatic system configuration when the system is initialized Chapter 1 Overview of NI VXI National Instruments Corporation 1 3 NI VXI User Manual Message Based Devices In addition to register based devices the VXIbus specification also defines message based devices which are required to have communication registers in addition to configuration registers All message based VXIbus devices regardless of the manufacturer can communicate at a minimum level using the VXI specified Word Serial Protocol In addition you can establish higher performance communication channels such as shared memory channels to take advantage of the VXIbus bandwidth capabilities Device Specific Protocols Device Specific Protocols Shared Memory Protocol 488 VXIbus Protocol Device Specific Protocols 488 2 Syntax Word Serial Protocol Communication Registers Configuration Registers Device Specific Protocols Figure 1 2 VXI Software Protocols Word Serial Protocol The VXIbus Word Serial Protocol is a standardized message passing protocol This protocol is functionally very similar to the IEEE 488 protocol which transfers data messages to and from devices one byte or word at a time Thus VXI message based devices communicate in Chapter
192. unction However because string communication is the most common use for Word Serial Protocol the functions WSwrt and WSrd use the Word Serial commands Byte Available for sending a byte to a servant and Byte Request for retrieving a byte from a Servant repetitively to send or receive strings as defined by the Word Serial Protocol In addition other common commands such as Clear have been encapsulated in their own functions such as WSclr Chapter 3 Software Overview describes all NI VXI functions pertaining to message based communication for the Commander However there are times when you want the controller to operate as a Word Serial Servant NI VXI allows for the controller to accept Word Serial commands from a Commander This chapter also describes a different set of functions that a Servant uses for message based communication with its Commander For example WSSrd Word Serial Servant Read sets up the controller to accept the Byte Request commands from a controller and respond with the string specified in the function In a similar fashion the WSSwrt function programs the controller to accept Byte Available commands National Instruments strongly recommends that if you want to program the controller as a Servant you should aim to become familiar with the Word Serial Protocol in detail and implement as much of the protocol as possible to simplify the debugging and operation of the program Chapter 2 Introduction to the
193. upport 3 8 Cooperative Multitasking Support 3 8 Multitasking Support 3 8 WSabort 3 10 WSclr 3 10 WScmd 3 10 WSEcmd 3 11 WSgetTmo 3 11 Table of Contents National Instruments Corporation vii NI VXI User Manual WSLcmd 3 11 WSLresp 3 11 WSrd 3 12 WSrdf 3 12 WSresp
194. utput parameters are based on VXI VME addresses not local CPU addresses The window parameter value should be the value returned from a MapVXIAddress call The VXI VME address space being accessed is inherent in the window parameter MapVXIAddress accessparms address timo window ret MapVXIAddress sets up a window into one of the VXI VME address spaces and returns a pointer to a local address that will access the specified VXI VME address The accessparms parameter specifies Owner Privilege Access Only Privilege the VXI VME address space the VXI VME access privilege and the byte ordering The value of the timo parameter gives the time in milliseconds that the process will wait checking for window availability The function returns immediately if the window is already available or if the timo value is 0 The timo field is ignored in a uniprocess nonmultitasking system The return value in window gives a unique window identifier that various calls such as GetWindowRange or GetContext use to get window settings When a request for Owner Privilege is granted you can also use this window identifier with calls such as SetContext or SetPrivilege to change the hardware context for that window Chapter 3 Software Overview NI VXI User Manual 3 32 National Instruments Corporation MapVXIAddressSize size MapVXIAddressSize sets the size for mapping user windows The subsequent calls to MapVXIAddress will attempt to map a window of
195. vant to receive a single command query written to its Data Low register Glossary NI VXI User Manual G 16 National Instruments Corporation WRviol Write Ready protocol violation a type of Word Serial Protocol error If a Commander attempts to write a command or query to a Servant that is not Write Ready already has a command or query pending a Write Ready protocol violation may be generated WSP See Word Serial Protocol National Instruments Corporation I 1 NI VXI User Manual Index A acceptor trigger functions AcknowledgeTrig 3 55 DefaultTrigHandler 3 55 DefaultTrigHandler2 3 55 DisableTrigSense 3 55 EnableTrigSense 3 55 GetTrigHandler 3 56 overview 3 54 SetTrigHandler 3 56 WaitForTrig 3 56 access functions See high level VXI VMEbus access functions local resource access functions low level VXI VMEbus access functions Access Only Privilege 3 28 to 3 29 AcknowledgeTrig function 3 55 AcknowledgeVXIint function 3 46 to 3 47 AssertSysreset function 3 60 AssertVXIint function 3 47 ASYNC trigger protocol 3 51 asynchronous events 1 4 to 1 5 B bulletin board support B 1 busacc h file 2 10 Byte Available BAV Word Serial commands 3 6 3 15 Byte Request BREQ Word Serial queries 3 6 3 15 C callback handlers handling signals or interrupts 2 18 system dependent behavior note 2 19 CloseVXIlibrary function description 3 2 requirements for NI VXI programs 2 10 to 2 11 Commander S
196. w number signifies that the access privileges to the window are Access Only Privilege With Access Only Privilege you cannot use the SetPrivilege SetByteOrder and SetContext calls in your application to dynamically change the hardware context No Access Only accessor can change the state of the window The initial Access Only call sets the hardware context for the window which cannot be changed until all Access Only accessors have called UnMapVXIAddress to free the window The functions GetPrivilege GetByteOrder and GetContext will succeed regardless of whether the caller has Owner Privilege or Access Only Privilege The following paragraphs describe the low level VXIbus access functions The descriptions are presented at a functional level describing the operation of each of the functions The functions are grouped by area of functionality Note On MITE based platforms MapVXIAddress cannot be called while the CPU is in interrupt context For this reason it is recommended that you not use the SaveContext and RestoreContext functions Due to the multiple window support of the MITE you should not need these functions Chapter 3 Software Overview NI VXI User Manual 3 30 National Instruments Corporation GetByteOrder window ordermode GetByteOrder retrieves the byte word order of data transferred into or out of the specified window The two possible settings are Motorola most significant byte word first or Intel least sig
197. ween the mainframes Chapter 3 Software Overview NI VXI User Manual 3 68 National Instruments Corporation you can use MapTTLtrig to configure the mainframe to mainframe mapping The NI VXI Resource Manager automatically configures a default mapping based on the user modifiable configuration files The MapTTLtrig function can dynamically reconfigure the TTL trigger mapping Only special circumstances should require any changes to the default configuration MapUtilBus extender modes MapUtilBus configures mainframe extender utility bus hardware to map Sysfail ACfail and or Sysreset for the specified mainframe into and or out of the mainframe If the specified frame extender can extend the VXI VME utility signals between mainframes you can use MapUtilBus to configure the mainframe to mainframe mapping The NI VXI Resource Manager automatically configures a default mapping based on user modifiable configuration files The MapUtilBus function can dynamically reconfigure the utility bus mapping Only special circumstances should require any changes to the default configuration MapVXIint extender levels directions MapVXIint changes the VXI VME interrupt extension configuration in multiple mainframe configurations If the specified frame extender can extend the VXI VME interrupts between mainframes you can use MapVXIint to configure the mainframe to mainframe mapping The NI VXI Resource Manager automatically configures a default
198. xt Low Level VXI VMEbus Access SetDevInfo System Configuration SetDevInfoLong System Configuration SetDevInfoShort System Configuration SetDevInfoStr System Configuration SetMODID Local Resource Access SetPrivilege Low Level VXI VMEbus Access Appendix A Function Classification Reference National Instruments Corporation A 11 NI VXI User Manual Table A 2 Function Listing by Name Function Group VXI VME C C BASIC SetSignalHandler VXI Signal SetSoftResetHandler System Interrupt Handler SetSysfailHandler System Interrupt Handler SetSysresetHandler System Interrupt Handler SetTrigHandler Triggers SetVXIintHandler VXI VME Interrupt SetWSScmdHandler Servant Word Serial Protocol SetWSSEcmdHandler Servant Word Serial Protocol SetWSSLcmdHandler Servant Word Serial Protocol SetWSSrdHandler Servant Word Serial Protocol SetWSSwrtHandler Servant Word Serial Protocol SignalDeq VXI Signal SignalEnq VXI Signal SignalJam VXI Signal SrcTrig Triggers TrigAssertConfig Triggers TrigCntrConfig Triggers TrigExtConfig Triggers TrigTickConfig Triggers UnMapTrigToTrig Triggers UnMapVXIAddress Low Level VXI VMEbus Access VXIin High Level VXI VMEbus Access VXIinLR Local Resource Appendix A Function Classification Reference NI VXI User Manual A 12 National Instruments Corporation Table A 2 Function Listing by Name Function Group VXI V
199. you plan to use any of the advanced features of the TIC please contact National Instruments for the technical note Triggering with NI VXI Acceptor Trigger Functions The NI VXI acceptor trigger functions act as a standard interface for sensing accepting TTL and ECL triggers as well as for sending acknowledgments back to the sourcing device These functions can sense any of the VXI defined trigger protocols on the local embedded controller or external extended controller s Use the EnableTrigSense function to prepare for the sensing of any of the trigger protocols If the protocol requires an acknowledgment you should call the AcknowledgeTrig function when appropriate You can use SetTrigHandler to install a callback handler for the specified trigger line A default handler DefaultTrigHandler is installed for each one of the trigger lines when InitVXIlibrary is called and will call AcknowledgeTrig for you You can use the SetTrigHandler function at any time to replace the default handlers In addition you can use the WaitForTrig function to accommodate applications that do not want to install callback handlers Chapter 3 Software Overview National Instruments Corporation 3 55 NI VXI User Manual AcknowledgeTrig controller line AcknowledgeTrig performs the required trigger acknowledgments for the ASYNC or SEMI SYNC VXI defined protocol as configured via the EnableTrigSense function DefaultTrigHandler controller line t
200. ype DefaultTrigHandler is the sample handler for the receiving acknowledges and sensing triggers and is automatically installed after a call to InitVXIlibrary After a call to EnableTrigSense for a particular VXI trigger line protocol the trigger handler for a specific trigger line is called when the sourced trigger is sensed from the sourcing device If the configured VXI trigger protocol requires an acknowledgment either ASYNC or SEMI SYNC you must call the AcknowledgeTrig function to perform the acknowledgment DefaultTrigHandler calls the AcknowledgeTrig function if the type parameter specifies that an acknowledge interrupt occurred Otherwise DefaultTrigHandler performs no operations DefaultTrigHandler2 controller line type DefaultTrigHandler2 is a sample handler for receiving trigger interrupt sources similar to DefaultTrigHandler DefaultTrigHandler2 performs no operations Any required acknowledgments must be performed by the application DisableTrigSense controller line DisableTrigSense unconfigures and desensitizes the triggering hardware that was enabled by the EnableTrigSense function to generate interrupts when any VXI defined trigger protocol is sensed on the specified trigger line EnableTrigSense controller line prot EnableTrigSense configures and sensitizes the triggering hardware to generate interrupts when the specified VXI defined trigger protocol is sensed on the specified trigger line When Enable
201. ypedef unsigned char UINT8 8 bit unsigned integer typedef short INT16 16 bit signed integer typedef unsigned short UINT16 16 bit unsigned integer typedef long INT32 32 bit signed integer typedef unsigned long UINT32 32 bit unsigned integer Input Versus Output Parameters Because all C C function calls pass function parameters by value not by reference you must specify the address of the parameter when the parameter is an output parameter The C C amp operator accomplishes this task For example ret VXIinReg la reg amp value Chapter 2 Introduction to the NI VXI Functions National Instruments Corporation 2 5 NI VXI User Manual Because value is an output parameter amp value is used when calling the function instead of value The input parameters are la and reg Return Values and System Errors All NI VXI functions return a status indicating success or failure The return code of 0x8000 is reserved as a return status value for any function to signify that a system error occurred during the function call except for the commander word serial operations This error is specific to the operating system on which the NI VXI interface is running Multiple Mainframe Support The NI VXI functions described in this manual support multiple mainframes both in external CPU configurations and embedded CPU configurations The Startup Resource Manager supports one or more

Download Pdf Manuals

Related Search

Related Contents

Livre " Réhabiliter les maisons ordinaires de l`époque industrielle "  Lisséa - Applimo  TRSE 6000 - Burg Wächter  http://casio.jp/projector/yc_400/ http://casio.jp/projector/    QuickPro® PUMP HEAD REPLACEMENT  RV-RVR _A12-0311 rev2.pmd - Categories On Jamieson  InfraSpec NR800 Fourier Transform Near-Infrared    

Copyright © All rights reserved. Failed to retrieve file