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MPASM USER'S GUIDE

1. Table E 1 MPASM Directive Language Summary Continued Directive Description Syntax SET Define an Assembler Variable label set lt expr gt SPACE Insert Blank Listing Lines space lt expr gt SUBTITLE Specify Program Subtitle subtitl lt sub_text gt TITLE Specify Program Title title lt title_text gt UNDEFINE Delete a Substitution Label undefine lt label gt VARIABLE Declare Symbol Variable variable label expr label lt expr gt CONDITIONAL ASSEMBLY ELSE Begin Alternative Assembly Block to IF else ENDIF End Conditional Assembly Block endif ENDW End a While Loop endw IF Begin Conditionally Assembled Code if lt expr gt Block IFDEF Execute If Symbol is Defined ifdef label IFNDEF Execute If Symbol is Not Defined ifndef label WHILE Perform Loop While Condition is True while lt expr gt DATA CBLOCK Define a Block of Constants cblock lt expr gt _ CONFIG Set configuration fuses _ _ config expr DATA Create Numeric and Text Data data lt expr gt lt expr gt lt expr gt data lt text_string gt lt text_string gt DB Declare Data of One Byte db lt expr gt lt expr gt lt expr gt DE Declare EEPROM Data de lt expr gt lt expr gt lt expr gt DT Define Table dt lt expr gt lt expr gt lt expr gt DW Declare Data of One Word dw lt expr gt lt expr gt lt expr gt ENDC End an Automatic Const
2. Example 2 4 Sample MPASM Listing File LST MPASM 01 99 21 Intermediate MANUAL ASM 5 30 1997 15 31 05 PAGE 1 LOC OBJECT CODE LINE SOURCE TEXT VALUE 00001 00002 Sample MPASM Source Code For illustration only 00003 00004 list p 16c54 0000000B 00005 Dest equ H OB 00006 01FF 00007 org H O1FF 01FF 0A00 00008 goto Start 00009 0000 00010 org H 0000 00011 0000 OCOA 00012 Start moviw H OA 0001 002B 00013 movwf Dest 0002 0A00 00014 goto Start 00015 00016 end MPASM 01 99 21 Intermediate MANUAL ASM 5 30 1997 15 31 05 PAGE 2 SYMBOL TABLE LABEL VALUE Dest 0000000B Start 00000000 1l6C54 00000001 MEMORY USAGE MAP X Used Unused 0000 MX XH Sse 5222 Se se 2 9 Se Se a o SS Se See So aes Sse ease OIGO e gt 23522222252 2522332325592 SSS Seen Se esa Sea AS SR X All other memory blocks unused Program Memory Words Used 4 Program Memory Words Free 508 Errors 0 Warnings 0 reported 0 suppressed Messages 0 reported 0 suppressed O 1997 Microchip Technology Inc DS33014F page 21 mi gt S MPASM USER S GUIDE with MPLINK and MPLIB The listing file format produced by MPASM is straight forward The product name and version the assembly date and time and the page number appear at the top of every page The first column of numbers four characters wide contains the base address in memory where the code will be placed The second column i
3. Executable code and data must be defined in an appropriate section When generating an object file all executable code and data declarations must be placed within appropriate sections Page or Bank bits cannot be evaluated for the operand The operand of a PAGESEL BANKSEL or BANKISEL directive must be of the form relocatable address label or constant Each object file section must be contiguous Object file sections except UDATA OVR sections cannot be stopped and restarted within a single source file To resolve this problem either name each section with its own name or move the code and data declarations such that each section is contiguous This error will also be generated if two sections of different types are given the same name All overlayed sections of the same name must have the same starting address If multiple UDATA OVR sections with the same name are declared they must all have the same starting address Operand must be an address label When generating object files only address labels in code or data sections may be declared global Variables declared by the SET or EQU directives may not be exported UNKNOWN ERROR An error has occurred which MPASM cannot understand It is not any of the errors described in this appendix Contact your Microchip Field Application Engineer FAE if you cannot debug this error Symbol not previously defined Symbol being undefined was not previously defined Argume
4. 1997 Microchip Technology Inc DS33014F page 23 MPASM USER S GUIDE with MPLINK and MPLIB Table 3 1 Directive Summary Directive Description Syntax BADRAM Specify invalid RAM locations badram lt expr gt BANKISEL Genrate RAM bank selecting code for bankisel label indirect addressing BANKSEL Generate RAM bank selecting code banksel label CBLOCK Define a Block of Constants cblock lt expr gt CODE Begins executable code section lt name gt code lt address gt _ CONFIG Specify configuration bits __config lt expr gt CONSTANT Declare Symbol Constant constant lt label gt lt expr gt lt label gt lt expr gt DATA Create Numeric and Text Data lt label gt data lt expr gt lt expr gt lt expr gt lt label gt data lt text_string gt lt text_string gt DB Declare Data of One Byte lt label gt db lt expr gt lt expr gt lt expr gt lt label gt db text string text string DE Define EEPROM Data lt label gt de lt expr gt lt expr gt lt expr gt lt label gt de text string text string DEFINE Define a Text Substitution Label define lt name gt lt value gt define lt name gt arg arg lt value gt DT Define Table lt label gt dt lt expr gt lt expr gt lt expr gt lt labe
5. Chapter 3 are packed two to a word with the first character in the most significant byte of the word If an odd number of characters are given in a string the final byte is zero When generating an object file this directive can also be used to declare initialized data values Refer to the IDATA directive for more information Example pa mi gt S data reloc_label 10 constants data 1 2 ext label constants externals data testing 1 2 3 text string data N single character data start_of_program relocatable label See Also DW DB DE DT IDATA DB Declare Data of One Byte Syntax lt label gt db lt expr gt lt expr gt lt expr gt Description Reserve program memory words with packed 8 bit values Multiple expressions continue to fill bytes consecutively until the end of expressions Should there be an odd number of expressions the last byte will be zero When generating an object file this directive can also be used to declare initialized data values Refer to the IDATA directive for more information Example db ELA OROT ely Ox f OSs OxOf t Xn See Also DATA DW DT DE IDATA DE Declare EEPROM Data Byte Syntax lt label gt de lt expr gt lt expr gt lt expr gt Description Reserve memory words with 8 bit data Each lt expr gt must evaluate to an 8 bit value The upper bits of the program word are zeroes Each character in a string
6. A library is a collection of relocatable object modules It is created by assembling multiple source files to object files and then using the librarian to combine the object files into one library file A library can be linked with object modules and other libraries to create executable code Libraries are created and manipulated with Microchip s librarian MPLIB DS33014F page 8 O 1997 Microchip Technology Inc Chapter 1 v D Link E Linking is the process of combining object files and libraries to create l executable code Linking is performed by Microchip s linker MPLINK Listing File y A listing file is an ASCII text file that shows the machine code generated for o each assembly instruction MPASM directive or macro encountered in a lt source file Macro Amacro consists of a sequence of assembler commands Passing arguments to a macro allows for flexible functionality Macros are a form of short hand notation that will be expanded by MPASM Mnemonics These are instructions that are translated directly into machine code These are used to perform arithmetic and logical operations on data residing in program or data memory of a microcontroller They also have the ability to move data in and out of registers and memory as well as change the flow of program execution Also referred to as Opcodes Object File An object file can be created to provide the user with a relocatable module that can be lin
7. Begin an Object File Uninitialized Data Section Syntax lt label gt udata lt RAM address gt Description For use when generating an object file Declares the beginning of a section of uninitialized data If lt 1abe1 gt is not specified the section is named udata The starting address is initialized to the specified address or zero if no address is specified No code can be generated in this segment The RES directive should be used to reserve space for data For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example udata Varl res 1 Double res 2 See Also TEXT IDATA UDATA OVR UDATA SHR EXTERN GLOBAL UDATA OVR Begin an Object File Overlayed Uninitialized Data Section Syntax lt label gt udata_ovr lt RAM address gt DS33014F page 52 1997 Microchip Technology Inc Chapter 3 Description For use when generating an object file Declares the beginning of a section of overlayed uninitialized data If lt 1abe1 gt is not specified the section is named udata ovr The starting address is initialized to the specified address or zero if no address is specified The space declared by this section is overlayed by all other udata ovr sections of the same name It is an ideal way of declaring temporary variables since it allows multiple variables to be declared at the same memory location No code can be generated in this segment The RES directive should be use
8. r add replace member if MEMBER s exist in the LIBRARY then they are replaced otherwise MEMBER is appended to the end of the LIBRARY x extract member if MEMBER s exist in the LIBRARY then they are extracted If no MEMBER is specified all members will be extracted q quiet mode no output is displayed U D oO U us O 1997 Microchip Technology Inc DS33014F page 99 MPASM USER S GUIDE with MPLINK and MPLIB Usage Examples Tips Suppose a library named dsp lib is to be created from three object modules named fft o fir o and iir o The following command line would produce the desired results mplib c dsp lib fft o fir o iir o To display the names of the object modules contained in a library file names dsp lib the following command line would be appropriate mplib t dsp lib MPLIB creates library files that may contain only a single external definition for any symbol Therefore if two object modules define the same external symbol MPLIB will generate an error if both object modules are added to the same library file To minimize the code and data space which results from linking with a library file the library s member object modules should be as small as possible Creating object modules that contain only a single function can significantly reduce code space Error Reporting MPLIB detects the following sources of error and reports them Parse Errors invalid swi
9. PIC16CXX Instruction Set The PIC16CXX Microchip s mid range 8 bit microcontroller family uses a 14 bit wide instruction set The PIC16CXX instruction set consists of 36 instructions each a single 14 bit wide word Most instructions operate on a file register f and the working register W accumulator The result can be directed either to the file register or the W register or to both in the case of some instructions A few instructions operate solely on a file register BSF for example The instruction set is grouped into the following catagories Table E 8 PIC16CXX Literal and Control Operations Hex Mnemonic Description Function 3Ekk ADDLW k Add literal to W k W oW 39kk ANDLW k AND literal and W k AND W gt W 2kkk CALL k Call subroutine PC 1 gt TOS k gt PC 0064 CLRWDT T Clear watchdog timer 0 gt WDT and Prescaler if assigned 2kkk GOTO k Goto address k is nine bits k PC 9 bits 38kk IORLW k Incl OR literal and W k OR W gt W 30kk MOVLW k Move Literal to W kW 0062 OPTION Load OPTION register W OPTION Register 0009 RETFIE Return from Interrupt TOS gt PC 1 GIE 34kk RETLW k Return with literal in W k gt W TOS gt PC 0008 RETURN Return from subroutine TOS gt PC 0063 SLEEP Go into Standby Mode 0 gt WDT stop oscillator 3Ckk SUBLW k Subtract W from literal k WO
10. Unknown section type for secName in file File An input object or library module is not of the proper file type or it may be corrupted Section types for secName do not match across input files A section with the name secName may occur in more than one input file All input files which have this section must also have the same section type Section secName is absolute but occurs in more than one input file An absolute section with the name secName may only occur in a single input file Relocatable sections with the same name may occur in multiple input files Either remove the multiple absolute sections in the source files or use relocatable sections instead Section share types for secName do not match across input files A section with the name secName occurs in more than one input file however in some it is marked as a shared section and in some it is not Change the section s share type in the source files and rebuild the object modules Section secName contains code and can not have a RAM memory attribute specified in the linker command file Use only the ROM attribute when defining the section in the linker command file Section secName contains uninitialized data and can not have a ROM memory attribute specified in the linker command file Use only the RAM attribute when defining the section in the linker command file Section secName contains initialized data and can not have a ROM memory attribute
11. c mplab lib c program filesimplink O 1997 Microchip Technology Inc DS33014F page 119 MPASM USER S GUIDE with MPLINK and MPLIB unknown switch cmdline token An unrecognized command line switch was supplied Refer to the Usage documentation for the list of supported Switches Linker Errors Memory memName overlaps memory memName All CODEPAGE blocks must specify unique memory ranges which do not overlap Similarly DATABANK and SHAREBANK blocks may not overlap Duplicate definition of memory memName All CODEPAGE and DATABANK directives must have unique NAME attributes Multiple map files declared File1 File2 The m lt mapfile gt switch was specified more than once Multiple output files declared File1 File2 The o lt outfile gt switch was specified more than once Mutliple inclusion of object file File1 File2 An object file has been included multiple times either on the command line or with a FILES directive in a linker command file Remove the multiple references Overlapping definitions of SHAREBANK memName A SHAREBANK directive specifies a range of addresses that overlap a previous definition Overlaps are not permitted Inconsistent length definitions of SHAREBANK memName All SHAREBANK definitions which have the same NAME attribute must be of equal length Multiple STACK definitions A STACK directive occurs more than once in the linker command file or
12. lt 1abe1 gt Only one 1abel should be specified No operations can be performed on 1abel label musthave been previously defined DS33014F page 26 O 1997 Microchip Technology Inc Chapter 3 UU Q The linker will generate the appropriate bank selecting code For 14 bit core devices the appropriate bit set clear instruction on the IRP bit in the STATUS register will be generated For the 16 bit core devices MOVLB or MOVLR will be generated If the user can completely specify the indirect address without U these instructions no code will be generated gt For more information refer to Chapter 4 Using MPASM to Create o Relocatable Objects Example moviw Varl movwf FSR bankisel Varl movwf INDF See Also PAGESEL BANKSEL BANKSEL Generate Bank Selecting Code Syntax banksel label Description For use when generating an object file This directive is an instruction to the linker to generate bank selecting code to set the bank to the bank containing the designated 1abel Only one 1abel should be specified No operations can be performed on 1abel label must have been previously defined The linker will generate the appropriate bank selecting code For 12 bit core devices the appropriate bit set clear instructions on the FSR will be generated For 14 bit devices bit set clear instructions on the STATUS register will be generated For the 16 bit core devi
13. size and address Shared Section A section which resides in a shared non banked region of data RAM Stack An area in data memory where function arguments return values local variables and return addresses are stored Symbol A symbol is a general purpose mechanism for describing the various pieces which comprise a program These pieces include function names variable names section names file names struct enum union tag names etc Unassigned Section A section which has not been assigned to a specific target memory block in the linker command file The linker must find a target memory block in which to allocate an unassigned section Uninitialized Data Data which is defined without an initial value In C int myVar defines a variable which will reside in an uninitialized data section DS33014F page 96 O 1997 Microchip Technology Inc AN MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Part 3 MPLIB Chapter 1 Librarian Fundamentals ooooooooocmmommom 99 U o oO U us O 1997 Microchip Technology Inc DS33014F page 97 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 98 O 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 1 Librarian Fundamentals A librarian manages the creation and modification of library files A library file is simply a collection of object modules that are stored in a single f
14. through MPLAB the options screen is not available Refer to the Make Setup option in the MPLAB User s Guide for selecting assembly options in MPLAB Select a source file by typing in the name or using the Browse button Set the various options as described below Then click Assemble to assemble the source file Option Usage Radix Override any source file radix settings Warning Level Override any source file message level settings Hex Output Override any source file hex file format settings Generated Files Enable disable various output files Case Sensitivity Enable disable case sensitivity Macro Expansion Override any source file macro expansion settings Processor Override any source file processor settings Tab Size Set the list file tab size Extra Options Any additional command line options See Chapter 2 Command Line Interface Save Settings on Exit Save these settings in MPLAB INI Source Code Formats The source code file may be created using any ASCII text file editor It should conform to the following basic guidelines Each line of the source file may contain up to four types of information labels mnemonics operands comments The order and position of these are important Labels must start in column one Mnemonics may start in column two or beyond Operands follow the mnemonic Comments may fo
15. 112 113 114 115 116 117 118 119 120 Unmatched An open parenthesis did not have a matching close parenthesis For example DATA 1 2 Unmatched An close parenthesis did not have a matching open parenthesis For example DATA 1 2 Missing symbol An EQU or SET statement did not have a symbol to assign the value to Missing operator An arithmetic operator was missing from an expression For example DATA 1 2 Symbol not previously defined A symbol was referenced that has not yet been defined Only addresses may be used as forward references Constants and variables must be declared before they are used Divide by zero Division by zero encountered during an expression evaluation Duplicate label A label was declared as a constant e g with the EQU or CBLOCK directive in more than one location Address label duplicated or different in second pass The same label was used in two locations Alternately the label was used only once but evaluated to a different location on the second pass This often happens when users try to write page bit setting macros that generate different numbers of instructions based on the destination Address wrapped around 0 The location counter can only advance to FFFF After that it wraps back to 0 Overwriting previous address contents Code was previously generated for this address Code too fragmented The code is broken into too many pi
16. C FF FS lt L D cr es M m E SO RS gt N A n F st us UE ERE o DEL DS33014F page 140 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Appendix F Example Initialization Code Initialization Code If the IDATA directive is used when generating an object module the user must provide code to perform the data initialization The following two examples may be used and modified as needed Initialization Code for the PIC16CXX KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KK KKK KKK KKK KKK KKK kckckck kockck ck ckock kckckck KK KKK ANS PIC16Cxx MPASM Initialized Data Startup File Version 0 01 ae pure c Copyright 1997 Microchip Technology aid KKK KKK KKK KKK KKK KKK KKK KK KK KKK KKK KKK KKK KK KKK KKK KK KKK KK KKK KKK KKK KKK KK KKK A a Environment variables E VARIABLE TABLE OFFSET 0 Offset for reading from table of entries A O Equates A Register addresses INDF equ 0x00 PCL equ 0x02 STATUS equ 0x03 FSR equ 0x04 PCLATH equ 0x0A Bits within registers Z equ 0x02 C equ 0x00 IRP equ 0x07 STRESS SERES TI External variables and labels gt EXTERN _cinit Start of const data table AS E SN REA IE XE lA VS T COPY ROM WORD TO RAM Reads a 16 bit word stored in program memory as a pair of retlw kk instructions and store
17. CBLOCK in the source file has no starting value specified this message will be generated 314 UNKNOWN MESSAGE A message has occurred which MPASM cannot understand It is not any of the messages described in this appendix Contact your Microchip Field Application Engineer FAE if you cannot debug this message 1997 Microchip Technology Inc DS33014F page 117 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 118 1997 Microchip Technology Inc MICROCHIP MPASM USER S GUIDE with MPLINK and MPLIB Appendix D MPLINK Errors Warnings Parse Errors Invalid attributes for memory in cmdfile line A CODEPAGE DATABANK or SHAREBANK directive does not specify a NAME START or END attribute or another attribute is specified which is not valid Invalid attributes for STACK in cmdfile line A STACK directive does not specify a SIZE attribute or another attribute is specified which is not valid Invalid attributes for SECTION in cmdfile line A SECTION directive must have a NAME and either a RAM or ROM attribute Could not open cmdfile A linker command file could not be opened Check that the file exists is in the current search path and is readable Multiple inclusion of linker command file cmdfile A linker command file can only be included once Remove multiple INCLUDE directives to the referenced linker command file Illegal lt libpath gt for LIBPATH in cmdfile
18. File 2 0 e eee eee eee eee eens 89 Chapter 5 Linker Processing eee eee ee eee eee eens 91 Chapter 6 Terminology ccc eee eee eee eee n BB 95 y y N m A 1997 Microchip Technology Inc DS33014F page 77 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 78 O 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 1 Introduction MPLINK Preview What is MPLINK MPLINK is a linker for the Microchip C compiler MPLAB C and the Microchip relocatable assembler MPASM MPLINK is introduced with MPLAB C v1 75 xx pre release and beta test versions of v2 00 and MPASM v2 00 and can only be used with these or later versions How MPLINK Helps You MPLINK allows you to produce modular re usable code with MPLAB C and MPASM Control over the linking process is accomplished through a linker script file and with command line options MPLINK ensures that all symbolic references are resolved and that code and data fit into the available PICmicro device What you need to know to use MPLINK MPLINK is one tool in the MPASM and MPLAB C tool set You should be familiar with MPASM and with MPLAB C if you are using the compiler You should understand the basic architecture of the PICmicros especially the ROM and RAM memory maps You should also familiarize yourself with MPLIB the librarian Product Description MPLI
19. Interest Groups or SIGs as they are commonly referred to provide you with the opportunity to discuss issues and topics of interest with others that share your interest or questions SIGs may provide you with information not available by any other method because of the broad background of the PICmicro MCU user community There are SIGs for most Microchip systems and device families These groups are monitored by the Microchip staff Files Microchip regularly uses the Microchip BBS to distribute technical information application notes source code errata sheets bug reports and interim patches for Microchip systems software products Users can contribute files for distribution on the BBS For each SIG a moderator monitors scans and approves or disapproves files submitted to the SIG No executable files are accepted from the user community in general to limit the spread of computer viruses Mail The BBS can be used to distribute mail to other users of the service This is one way to get answers to your questions and problems from the Microchip staff as well as keeping in touch with fellow Microchip users worldwide Consider mailing the moderator of your SIG or the SYSOP if you have ideas or questions about Microchip products or the operation of the BBS Software Releases Software products released by Microchip are referred to by version numbers Version numbers use the form XX YY ZZ Where xx is the major release number y y i
20. Question mark character 3F Y Single quote apostrophe 27 V Double quote character 22 1000 Octal number zero Octal digit Octal digit xHH Hexadecimal number 1997 Microchip Technology Inc DS33014F page 73 MPASM USER S GUIDE with MPLINK and MPLIB Numeric Constants and Radix MPASM supports the following radix forms hexadecimal decimal octal binary and ASCII The default radix is hexadecimal the default radix determines what value will be assigned to constants in the object file when they are not explicitly specified by a base descriptor Constants can be optionally preceded by a plus or minus sign If unsigned the value is assumed to be positive Note Intermediate values in constant expressions are treated as 32 bit unsigned integers Whenever an attempt is made to place a constant in a field for which it is too large a truncation warning will be issued The following table presents the various radix specifications Table 6 2 Radix Specifications Type Syntax Example Decimal D digits D 100 Hexadecimal H hex digits H 9 Octal O octal digits o TTT Binary B binary digits B 00111001 ASCII character od A lt character gt A C DS33014F page 74 O 1997 Microchip Technology Inc Chapter 6 Table 6 3 Arithmatic Operators and Precedence gt
21. Queue QUEUE SIZE QueueHeadm QueueTail Doublel1 2 Double2 2 endc A eee DS33014F page 28 O 1997 Microchip Technology Inc Chapter 3 U See Also ENDC CODE Begin an Object File Code Section gt Syntax o lt label gt code lt ROM address gt z Description For use when generating an object file Declares the beginning of a section of program code If 1abe1 is not specified the section is named code The starting address is initialized to the specified address or zero if no address is specified For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example RESET code H O1FF goto START See Also IDATA UDATA UDATA OVR UDATA SHR EXTERN GLOBAL _ CONFIG Set Processor Configuration Bits Syntax _ config lt expr gt Description Sets the processor s configuration bits to the value described by lt expr gt Refer to the PICmicro Microcontroller Data Book for a description of the configuration bits for each processor Before this directive is used the processor must be declared through the command line the LIST directive or the PROCESSOR directive If this directive is used with the PIC17CXX family the hex file output format must be set to INHX32 through the command line or the LIST directive Example list p 17c42 f INHX32 _ _config H FFFF Default configuration bits 1997 Microchip Technology Inc DS33014F page 29
22. WWW for the current production release Systems Information and Upgrade Hot Line The Systems Information and Upgrade Line provides system users a listing of the latest versions of all of Microchip s development systems software products Plus this line provides information on how customers can receive any currently available upgrade kits The Hot Line Numbers are 1 800 755 2345 for U S and most of Canada and 1 602 786 7302 for the rest of the world These phone numbers are also listed on the Important Information sheet that is shipped with all development systems The hot line message is updated whenever a new software version is added to the Microchip BBS or when a new upgrade kit becomes available mca RR RED RENE RR HUI a na DS33014F page 108 O 1997 Microchip Technology Inc MICROCHIP MPASM USER S GUIDE with MPLINK and MPLIB Appendix C MPASM Errors Warnings Messages The following messages are produced by MPASM These messages always appear in the listing file directly above each line in which the error occurred The messages are stored in the error file ERR if no MPASM options are specified If the e option is used turns error file off then the messages will appear on the screen If the q quiet mode option is used with the e then the messages will not display on the screen or in an error file The messages will still appear in the listing file Errors 101 102 103 104 105 1
23. _ _MAXRAM defines the absolute maximum valid RAM address and initializes the map of valid RAM addresses to all addresses valid at and below lt expr gt lt expr gt must be greater than or equal to the maximum page O RAM address and less than 1000H This directive is designed for use with the _ _BADRAM directive Once the __ MAXRAM directive is used strict RAM address checking is enabled using the RAM map specified by _ BADRAM __ MAXRAM can be used more than once in a source file Each use redefines the maximum valid RAM address and resets the RAM map to all locations Example list p 16c622 _ _maxram H OBF a _badram H 07 H 09 H OD H IE _badram H 87 H 89 H 8D H 8F H OE movwf H 07 Generates invalid RAM warning movwf H 87 Generates invalid RAM warning and truncation message See Also BADRAM DS33014F page 46 O 1997 Microchip Technology Inc Chapter 3 f MESSG Create User Defined Message Syntax messg message text ds gt Description o z Causes an informational message to be printed in the listing file The message text can be up to 80 characters Issuing a MESSG directive does not set any error return codes Example mssg macro macro messg mssg macro 001 invoked without argument endm See Also ERROR NOEXPAND Turn off Macro Expansion Syntax noexpand Description Turns off macro expansion in the listing file See Also EXPAND
24. and SHAREBANK directives define data memory the CODEPAGE directive is used to define program memory The SHAREBANK directive identifies a region in RAM which is mapped across multiple banks Note a SHAREBANK directive should be given for each bank that shares a region and each of these directives should have the same NAME Not all PICmicros have shared RAM Check the data book and processor specific assembly files The PROTECTED attribute marks a memory block and prevents the linker from placing unassigned relocatable sections into the memory block The PROTECTED marking does not prevent the linker from placing absolute sections or assigned relocatable sections into the marked memory block Example To specify a logical block of program memory named constants that begins at address 0x100 and ends at address Ox1FF the following line should be added to the linker command file CODEPAGE NAME constants START 0x100 END 0x1FF Another Example The following example specifies a physical block of data memory named sfr which is shared across four banks The SHAREBANK s begin at offset 0x0 in each bank and end at offset OxF in each bank Each bank is 0x100 bytes long The PROTECTED attribute prevents the linker from placing any unassigned relocatable sections into the memory block SHAREBANK NAME sfr START 0x000 END 0x00F PROTECTED SHAREBANK NAME sfr START 0x100 END 0x10F PROTECTED SHAREBANK NAME sfr START 0x200 END 0x20F PRO
25. assembler instruction Example fill 0x1009 5 fill with a constant full GOTO RESET VECTOR NEXT BLOCK See Also DW ORG DATA GLOBAL Export a Label Syntax global label lt label gt Description For use when generating an object file Declares symbol names that are defined in the current module and should be available to other modules The GLOBAL statement must be after the lt 1abe1 gt is defined At least one label must be specified on the line For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example udata Varl res 1 Var2 res 1 global Varl Var2 code AddThree global AddThree addlw 3 return 1997 Microchip Technology Inc DS33014F page 39 MPASM USER S GUIDE with MPLINK and MPLIB See Also TEXT IDATA UDATA UDATA OVR UDATA SHR EXTERN IDATA Begin an Object File Initialized Data Section Syntax lt label gt idata lt RAM address gt Description For use when generating an object file Declares the beginning of a section of initialized data If lt 1abe1 gt is not specified the section is named idata The starting address is initialized to the specified address or zero if no address is specified No code can be generated in this segment The linker will generate a look up table entry for each byte specified in an idata section The user must then link or include the appropriate initialization code See Appendix E for examples of init
26. digit hexadecimal byte count representing the number of data bytes that will appear on the line AAAA is a four digit hexadecimal address representing the starting address of the data record TT isatwo digit record type record type that will always be 00 except for the end of file record which will be 01 HH is a two digit hexadecimal data byte presented in low byte high byte combinations CC is a two digit hexadecimal checksum that is the two s complement of the sum of all preceding bytes in the record Pec qct RR RR RR RR Ee O 1997 Microchip Technology Inc DS33014F page 101 MPASM USER S GUIDE with MPLINK and MPLIB Example lt file_name gt HEX 1000000000000000000000000000000000000000F0 0400100000000000EC 100032000000280040006800A800E800C80028016D 100042006801A9018901EA01280208026A02BF02C5 10005200E002E80228036803BF03E803C8030804B8 1000620008040804030443050306E807E807FF0839 06007200FF08FF08190A57 00000001FF 8 Bit Split Format HXL HXH The split 8 bit file format produces two output files HXL and HXH The format is the same as the normal 8 bit format except that the low bytes of the data word are stored in the HXL file and the high bytes of the data word are stored in the HXH file and the addresses are divided by two This is used to program 16 bit words into pairs of 8 bit EPROMs one file for Low Byte one file for High Byte Example file name HXL 0A000000000000000000000
27. eee 36 ERROR Issue an Error Message 00 e eee eere 36 ERRORLEVEL Set Message Level o0cooccococccco o 37 EXITM Exit from a Macro 1 RI 37 EXPAND Expand Macro Listing llee e 38 EXTERN Declare an Externally Defined Label o 38 FILL Specify Memory Fill Value llle 39 GLOBAL Exporta Label seseeeee ene 39 IDATA Begin an Object File Initialized Data Section 40 IDLOCS Set Processor ID Locations ooooooccoccococoo 41 IF Begin Conditionally Assembled Code Block 41 IFDEF Execute If Symbol has Been Defined oo oo 42 IFNDEF Execute If Symbol has not Been Defined 42 INCLUDE Include Additional Source File esses 43 LIST Listing Options 25 cepe eR IS Eee a Boe ER 44 LOCAL Declare Local Macro Variable oooooooooomooom 44 MACRO Declare Macro Definition llle 45 DS33014F page iv 1997 Microchip Technology Inc Table of Contents Chapter 4 Chapter 5 MAXRAM Define Maximum RAM Location o ooocooooooo 46 MESSG Create User Defined Message 0 eee eee eee 47 NOEXPAND Turn off Macro Expansion 0 000 eee eee eee 47 NOLIST Turn off Listing Output 0 0 0 ee eee 47 ORG Set Program Origin auauua anaana nananana anaa 48 PAGE Insert Listi
28. generates the output COFF file and map file The linker then translates the output COFF to a COD listing hex programming file The COD file format is the currently supported debugging file format for MPLAB Linker Components MPLINK is actually comprised of four separate programs The first program mplink exe is a shell program which invokes the other three programs The user only interacts with the mplink exe shell program DS33014F page 80 O 1997 Microchip Technology Inc Chapter 1 Introduction The shell program first invokes mplink exe which is the actual linker and passes it the command line options The linker generates an output COFF file and map file If the linker completes successfully the shell program then invokes mp2cod exe to translate the output COFF file into a COD file and a listing file If this step completes successfully the shell program then invokes mp2hex exe to translate the COFF file into a HEX programming file Tools and Supported Platforms MPLINK is distributed in two executable formats a Win32 console application suitable for Windows95 and WindowsNT platforms and a DOS extended DPMI application suitable for Windows 3 x and DOS platforms Executables which are DOS extended applications have names which end with d to distinguish them from the Win32 versions DOS extended versions require the DOS extender program DOS4GW EXE which is also distributed with MPLINK As mentioned in the
29. high portion into BSR goto Start copying data Well it s a banked GPR needing MOVLR type of bank switching init sec gpr First mask off high nibble of BSR moviw Ox0F andwf BSR 1 BANKSEL init_entry_to_addr 1 swapf init entry to addr 1 WREG Bank addr in hi nibble of WREG iorwf BSR 1 goto Start copying data Loop for of bytes to be copied p Since on 17Cxx we store two bytes per word we must be careful if the number of bytes to be copied is odd We cannot copy word by word or we may end up overwriting a byte in RAM that doesn t belong to the initialized data section We therefore must decrement and check the size for every low and high byte read from program memory Start copying data tablrd 0 1 WREG peer Test movfp init_entry_size WREG iorwf init entry size 1 0 btfsc ALUSTA Z goto dec num init SUR EUER Copy low byte kkkx tlrd 0 WREG movfp WREG INDFO Low byte stored in RAM location 7 Decrement decf init_entry_size 1 btfss ALUSTA C decf init_entry_size 1 1 O 1997 Microchip Technology Inc DS33014F page 151 MPASM USER S GUIDE with MPLINK and MPLIB P Test again movfp init entry size WREG iorwf init entry size 1 0 btfsc ALUSTA Z goto dec num init ERES Copy high byte FEET tlrd 1 WREG movfp WREG INDFO Decrement decf init_entry_size 1 btfss ALUSTA C decf init_entry_size 1 1 goto _start_copying_data Decrement th
30. included linker command files Remove the multiple STACK directives Undefined DATABANK SHAREBANK memName for STACK Duplicate definitions of SECTION secName Each SECTION directive must have unique NAME attributes Remove duplicate definitions Undefined CODEPAGE memName for SECTION secName A SECTION directive with a ROM attribute refers to a memory block which has not been defined Add a CODEPAGE directive to the linker command file for the undefined memory block Undefined DATABANK SHAREBANK memName for SECTION secName A SECTION directive with a RAM attribute refers to a memory block that has not been defined Add a DATABANK or SHAREBANK directive to the linker command file for the undefined memory block No input object files specified At least one object module must be specified either on the command line or in the linker command file using the FILES directive Could not find file File An input object or library file was specified which does not exist or cannot be found in the linker path DS33014F page 120 1997 Microchip Technology Inc Appendix D MPLINK Errors Warnings Processor types do not agree across all input files Each object module and library file specifies a processor type or a processor family All input modules processor types or families must match ROM width of xx not supported An input module specifies a processor whose ROM width is not 12 14 or 16 bits wide
31. is stored in a separate word 1997 Microchip Technology Inc DS33014F page 31 MPASM USER S GUIDE with MPLINK and MPLIB Although designed for initializing EEPROM data on the PIC16C8X the directive can be used at any location for any processor Example org H 2100 Initialize EEPROM Data de My Program v1 0 O See Also DATA DB DT DW DEFINE Define a Text Substitution Label Syntax define name lt string gt Description This directive defines a text substitution string Wherever name is encountered in the assembly code st ring will be substituted Using the directive with no st ring causes a definition of lt name gt to be noted internally and may be tested for using the IFDEF directive This directive emulates the ANSI C standard for define Symbols defined with this method are not available for viewing using MPLAB Example define length 20 define control 019 7 define position X Y Z Y 2 Z X test label dw position 1 length 512 bsf control set bit 7 in f19 See Also IFDEF IFNDEF UNDEFINE DT Define Table Syntax lt label gt dt lt expr gt lt expr gt lt expr gt DS33014F page 32 1997 Microchip Technology Inc Chapter 3 UU gts Description et oh Generates a series of RETLW instructions one instruction for each lt expr gt l Each lt expr gt must be an 8 bit value Each character in a string is stored in its own RETL
32. line The libpath must be a semicolon delimited list of directories Enclose directory name which have embedded spaces in double quotes Illegal lt Ikrpath gt for LKRPATH in cmdfile line The Ikrpath must be a semicolon delimited list of directories Enclose directory names which have embedded spaces in double quotes Illegal filename for FILES in cmdfile line An object or library filename must end with o or lib respectively Illegal filename for INCLUDE in cmdfile line A linker command filename must end with Ikr Unrecognized input in cmdfile line All statements in a linker command file must begin with a directive keyword or the comment delimiter o switch requires filename A COFF output filename must be specified For example o main out m switch requires filename A map filename must be specified For example m main map n switch requires length The number of source lines per listing file page must be specified A length of zero will suppress pagination of the listing file L switch requires lt pathlist gt A semicolon delimited path must be specified Enclose directory names containing embedded spaces with double quotes For example L c mplab lib c program filesimplink K switch requires lt pathlist gt A semicolon delimited path must be specified Enclose directory names containing embedded spaces with double quotes For example L
33. macro definition there will be no conflict between the two If the macro is called recursively each invocation will have its own local copy f mi gt S Example lt main code segment gt len equ 10 global version size equ 20 note that a local variable may now be created and modified test macro size local len label local len and label len set size modify local len label res len reserve buffer len set len 20 endm end macro See Also MACRO ENDM MACRO Declare Macro Definition Syntax label macro lt arg gt lt arg gt Description A macro is a sequence of instructions that can be inserted in the assembly source code by using a single macro call The macro must first be defined then it can be referred to in subsequent source code A macro can call another macro or may call itself recursively Please refer to Chapter 5 Macro Language for more information Example Read macro device buffer count movlw device movwf ram 20 moviw buffer buffer address O 1997 Microchip Technology Inc DS33014F page 45 MPASM USER __MAXRAM S GUIDE with MPLINK and MPLIB movwf ram 21 movlw count byte count call Sys 21 read file call endm See Also ENDM LOCAL IF ELSE ENDIF EXITM Define Maximum RAM Location Syntax _ maxram lt expr gt Description The _MAXRAM and _ _BADRAM directives together flag accesses to unimplemented registers
34. named a cod and a hex Usage Example Suppose there are two object files to be linked a o and b o a linker command file Ink17C44 Ikr a library file math lib and we want the linker to generate a mapfile c map an output COFF file c out an output COD file c cod and an output programming file c hex If the input files are in the current directory the following command line would produce the desired results mplink o c out m c map a o b o 1nk17C44 1kr DS33014F page 84 1997 Microchip Technology Inc MICROCHIP with MPLINK and MPLIB Chapter 3 Command File Directives MPASM USER S GUIDE A linker command file is an ASCII text file which is processed by the linker Linker command files can be created to control the operation of the linker The linker command file is used 1 To specify an additional directory for the library object search path 2 To specify an additional directory for the linker command file search path To specify additional object files and library files for linking To include additional linker command files To define the target processor s memory architecture To locate sections within the target processor s memory HO Or MDC To specify the size of the stack and optionally the target memory where it resides Each line in a linker command file is either a directive or a comment Any text following a is ignored The following directives are
35. of their sections The linker adjusts the symbol addresses based upon the ultimate location of their allocated sections After the linker has relocated the symbols defined in each input section it resolves external symbols The linker attempts to match all external symbol references with a corresponding symbol definition If any external symbol references do not have a corresponding symbol definition an attempt is made to locate the corresponding symbol definition in the input library files If the corresponding symbol definition is not found an error is generated If the resolution of external symbols was successful the linker then proceeds to patch each section s raw data Each section contains a list of relocation entries which associate locations in a section s raw data with relocatable symbols The addresses of the relocatable symbols are patched into the raw data The process of relocating symbols and patching sections is described below y 9 A N U A After the linker has processed all relocation entries it generates the executable output module Linker Allocation Algorithm The linker allocates sections to allow maximal control over the location of code and data called sections in target memory There are four kinds of allocations that the linker handles Sections can be absolute or relocatable non absolute and they can be assigned target memory blocks in the linker command file or they may be left un
36. specified in the linker command file Use only the RAM attribute when defining the section in the linker command file Section secName contains initialized rom data and can not have a RAM memory attribute specified in the linker command file Use only the ROM attribute when defining the section in the linker command file Section secName has a memory memName which can not fit the section Section secName lengthz OXHHHH The memory which was assigned to the section in the linker command file either does not have space to fit the section or the section will overlap another section Use the m mapfile switch to generate an error map file The error map will show the sections which were allocated prior to the error Section secName has a memory memName which is not defined in the linker command file Add a CODEPAGE DATABANK or SHAREBANK directive for the undefined memory to the linker command file Section secName can not fit the section Section secName length 0xHHHH A section which has not been assigned to a memory in the linker command file can not be allocated Use the m lt mapfile gt switch to generate an error map file The error map will show the sections which were 1997 Microchip Technology Inc DS33014F page 121 MPASM USER S GUIDE with MPLINK and MPLIB allocated prior to the error More memory must be made available by adding a CODEPAGE SHAREBANK or DATABANK directive or by rem
37. supported each one is described below LIBPATH LKRPATH FILES INCLUDE DATABANK CODEPAGE SHAREBANK SECTION and STACK LIBPATH Directive Library and object files which do not have a path are searched for using the library object search path The following directive appends additional search directories to the library object search path LIBPATH libpath where libpath is a semicolon delimited list of directories Example To append the current directory and the directory CAPROJECTSUNCLUDE to the library object search path the following line should be added to the linker command file LIBPATH C PROJECTS INCLUDE LKRPATH Directive Linker command files that do not have a path are searched for using the linker command file search path The following directive appends additional search directories to the linker command file search path LKRPATH lkrpath O 1997 Microchip Technology Inc DS33014F page 85 y 9 A N U A MPASM USER S GUIDE with MPLINK and MPLIB where Ikrpath is a semicolon delimited list of directories Example To append the current directory s parent and the directory CAPROJECTSSCRIPTS to the linker command file search path the following line should be added to the linker command file LKRPATH C PROJECTS SCRIPTS FILES Directive The following directive specifies object or library files for linking FILES objfile libfile objfile libfile
38. the directive will be assembled Assembly will be enabled or disabled until the next matching ELSE Or ENDIF directive is encountered DS33014F page 42 1997 Microchip Technology Inc Chapter 3 Example define testingl set testing on undefine testingl set testing off ifndef testingl if not in testing mode execute this path endif H end end of source See Also 2 DEFINE ELSE IFDEF UNDEFINE ENDIF INCLUDE Include Additional Source File Syntax include lt lt include_file gt gt include lt include_file gt Description The specified file is read in as source code The effect is the same as if the entire text of the included file were placed here Upon end of file source code assembly will resume from the original source file Up to six levels of nesting are permitted include file may be enclosed in quotes or angle brackets If a fully qualified path is specified only that path will be searched Otherwise the search order is current working directory source file directory MPASM executable directory Example include c sys sysdefs inc system defs include lt regs h gt register defs O 1997 Microchip Technology Inc DS33014F page 43 f mi gt S MPASM USER S GUIDE with MPLINK and MPLIB LIST Listing Options Syntax list lt list_option gt lt list_option gt Description Occurring on a line by itself the LIST directive has the eff
39. this screen you can fill in the name of the source file you want to assemble and other information Source File CAME Processor Type Error File Cross Reference File Listina File Hex Dump Type INHXSM HE Assemble to Object File No Tab y Move Cursor 3 io 2 Quit Type the name of your source file elp Source File Type the name of your source file The name can include a DOS path and wild cards If you use wild cards one of or a list of all matching files is displayed for you to select from To automatically enter ASM in this field press TAB Processor Type If you do not specify the processor in your source file use this field to select the processor Enter the field by using the arrow keys then toggle through the processors by pressing RET Error File An error file lt sourcename gt ERR is created by default To turn the error file off use the lt gt to move to the YES and press RET to change it to NO The error file name can be changed by pressing the TAB key to move to the shaded area and typing a new name Wild cards are not allowed Cross Reference File Modify this field as for the Error File It is used to optionally create a cross reference file lt sourcename gt XRF The name may be modified as for error file and again wild cards are not allowed DS33014F page 16 O 1997 Microchip Technology Inc Chapter 2 Listing File
40. 0 0307 Boston Microchip Technology Inc 5 Mount Royal Avenue Marlborough MA 01752 Tel 508 480 9990 Fax 508 480 8575 Chicago Microchip Technology Inc 333 Pierce Road Suite 180 Itasca IL 60143 Tel 630 285 0071 Fax 630 285 0075 Dallas Microchip Technology Inc 14651 Dallas Parkway Suite 816 Dallas TX 75240 8809 Tel 972 991 7177 Fax 972 991 8588 Dayton Microchip Technology Inc Two Prestige Place Suite 150 Miamisburg OH 45342 Tel 937 291 1654 Fax 937 291 9175 Los Angeles Microchip Technology Inc 18201 Von Karman Suite 1090 Irvine CA 92612 Tel 714 263 1888 Fax 714 263 1338 New York Microchip Technology Inc 150 Motor Parkway Suite 416 Hauppauge NY 11788 Tel 516 273 5305 Fax 516 273 5335 San Jose Microchip Technology Inc 2107 North First Street Suite 590 San Jose CA 95131 Tel 408 436 7950 Fax 408 436 7955 Toronto Microchip Technology Inc 5925 Airport Road Suite 200 Mississauga Ontario L4V 1W1 Canada Tel 905 405 6279 Fax 905 405 6253 ASIA PACIFIC Hong Kong Microchip Asia Pacific RM 3801B Tower Two Metroplaza 223 Hing Fong Road Kwai Fong N T Hong Kong Tel 852 2 401 1200 Fax 852 2 401 3431 India Microchip Technology Inc India Liaison Office No 6 Legacy Convent Road Bangalore 560 025 India Tel 91 80 229 0061 Fax 91 80 559 9840 Korea Microchip Technology Korea 168 1 Youngbo Bldg 3 Floor Samsung Dong Kangnam Ku Seo
41. 0000000F6 1000190000284068A8E8C82868A989EA28086ABFAA 10002900E0E82868BFE8C8080808034303E8E8FFDO 03003900FFFF19AD 00000001FF lt file_name gt HXH 0A0000000000000000000000000000F6 1000190000000000000000010101010102020202CA 100029000202030303030304040404050607070883 0300390008080AAA 00000001FF DS33014F page 102 1997 Microchip Technology Inc Appendix A Hex File Formats 32 Bit Hex Format HEX The extended 32 bit address hex format is similar to the hex 8 format described above except that the extended linear address record is output also to establish the upper 16 bits of the data address This is mainly used for 16 bit core devices since their addressable program memory exceeds 32 k words Each data record begins with a 9 character prefix and ends with a 2 character checksum Each record has the following format BBAAAATTHHHH HHHCC where BB is a two digit hexadecimal byte count representing the number of data bytes that will appear on the line AAAA is a four digit hexadecimal address representing the starting address of the data record TT isatwo digit record type 00 Data record 01 End of File record 02 Segment address record 04 Linear address record HH is a two digit hexadecimal data byte presented in low byte high byte combinations CC is a two digit hexadecimal checksum that is the two s complement of the sum of all preceding bytes in the record O 1997 Microchip
42. 06 107 108 ERROR User error invoked with the ERROR directive Out of memory Not enough memory for macros defines or internal processing Eliminate any TSR s close any open applications and try assembling the file again If this error was obtained using the Real Mode DOS executable try using either the Windows version MPASMWIN or DPMI version MPASM DP Symbol table full No more memory available for the symbol table Eliminate any TSR s close any open applications and try assembling the file again If this error was obtained using the Real Mode DOS executable try using either the Windows version MPASMWIN or DPMI version MPASM DP Temp file creation error Could not create a temporary file Check the available disk space Cannot open file Could not open a file If it is a source file the file may not exist If it is an output file the old version may be write protected String substitution too complex Too much nesting of defines Illegal digit An illegal digit in a number Valid digits are 0 1 for binary 0 7 for octal 0 9 for decimal and 0 9 a f and A F for hexadecimal Illegal character An illegal character in a label Valid characters for labels are alphabetic a f A F numeric 0 9 the underscore and the question mark Labels may not begin with a numeric O 1997 Microchip Technology Inc DS33014F page 109 MPASM USER S GUIDE with MPLINK and MPLIB 109 110 111
43. 0x0024 data static C MMPASMV2NMUL8X8 ASM Error Map File If a linker error is generated a complete map file can not be created However if the m option was supplied an error map file will be created The error map file contains only section information no symbol information is provided The error map file in conjunction with the error message should provide enough context to determine why a section could not be allocated DS33014F page 90 O 1997 Microchip Technology Inc n MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 5 Linker Processing A linker combines multiple input object modules into a single executable output module The input object modules may contain relocatable or absolute sections of code or data which the linker will allocate into target memory The target memory architecture is described in a linker command file This linker command file provides a flexible mechanism for specifying blocks of target memory and maps sections to the specified memory blocks If the linker can not find a block of target memory in which to allocate a section an error is generated The linker combines like named input sections into a single output section The linker allocation algorithm is described below Once the linker has allocated all sections from all input modules into target memory it begins the process of symbol relocation The symbols defined in each input section have addresses dependant upon the beginning
44. 143 1 MPASM USER S GUIDE with MPLINK and MPLIB Start of code that copies initialization data from program to data memory copy init data First read the count of entries _cinit COPY ROM WORD TO RAM cinit num init TABLE OFFSET TABLE OFFSET 2 For num init do copy data for each initialization entry Decrement num init every time and when it reaches 0 we are done copying initialization data loop num init BANKSEL num init movf num init W iorwf num init 1 0 btfss STATUS Z A If num_init is not down to 0 goto _copy_init_sec then we have more sections to copy goto end copy init data otherwise we re done copying data For a single initialization section read the starting addresses in both program and data memory as well as the number of bytes to copy copy init sec COPY ROM WORD TO RA TABLE OFFSET cinit init entry from addr TABLE OFFSET TABLE OFFSET 2 Increment by 2 since it s a word COPY ROM WORD TO RA TABLE OFFSET cinit init entry to addr TABLE OFFSET TABLE OFFSET 2 Increment by 2 since it s a word COPY ROM WORD TO RA TABLE OFFSET cinit init entry size TABLE OFFSET TABLE OFFSET 2 Increment by 2 since it s a word Check init entry size If it s 0 then go to the next entry in the table if it exits If init entry size is non zero then go ahead and copy the bytes Start copying data BANKSEL init entry size mo
45. 997 Microchip Technology Inc DS33014F page iii MPASM USER S GUIDE with MPLINK and MPLIB DII E A A A A eer deen eter ee eee Peat 23 Directive Details 0 A eB ES 26 BADRAM Identify Unimplemented RAM 20 e 0 eee 26 BANKISEL Generate Indirect Bank Selecting Code 26 BANKSEL Generate Bank Selecting Code o ooocooocooocoomo 27 CBLOCK Define a Block of Constants 2 0 0 eee eee eee 28 CODE Begin an Object File Code Section 0 29 CONFIG Set Processor Configuration Bits 2 29 CONSTANT Declare Symbol Constant 000200 00 eeee 30 DATA Create Numeric and Text Data 0 eee ee eee 30 DB Declare Data of One Byte 0 eee ee 31 DE Declare EEPROM Data Byte llle 31 DEFINE Define a Text Substitution Label o o oooooooo o 32 DI Define Fable ocn pi EYES IP RS 32 DW Declare Data of One Word o o coccocccoco ee 33 ELSE Begin Alternative Assembly Block to IF o o ooo o 33 END End Program Block oocooccoccocco eee 34 ENDC End an Automatic Constant Block 0 0 00 oo 34 ENDIF End Conditional Assembly Block 0000 eee eee 35 ENDM End a Macro Definition o ooooooooorooonooooo 35 ENDW End a While Loop o ooocooccoccronno a ida 35 EQU Define an Assembler Constant 000 00 eee eee
46. 9bff BTFSC f b Bit test skip if clear skip if f b 0 9bff BTFSS f b Bit test skip if set skip if f b 1 3bff BTG f b Bit toggle f NOT b gt b Table E 15 PIC17CXX Program Control Instructions Hex Mnemonic Description Function ekkk CALL k Subroutine call within 8k page PC 1 gt TOS k gt PC 12 0 k 12 8 gt PCLATH 4 0 PC 15 13 gt PCLATH 7 5 31ff CPFSEQ Compare f w skip if f w f W skip if f W 32ff CPFSGT Compare f w skip if f gt w f W skip if f gt W 30ff CPFSLT Compare f w skip if f lt w f W skip if f lt W 16ff DECFSZ d Decrement f skip if 0 1 gt d skip if O 26ff DCFSNZ d Decrement f skip if not 0 1 gt d skip if not 0 Ckkk GOTO k Unconditional branch within 8k k gt PC 12 0 k 12 8 gt 3 4 0 PC 15 13 gt 3 7 5 leff NCFSZ d Increment f skip if zero 41 d skip if 0 24ff NFSNZ d Increment f skip if not zero 1 d skip if not 0 b7kk LCALL k Long Call within 64k PC 1 gt TOS k gt PCL PCLATH PCH 0005 RETFIE Return from interrupt enable 3 gt PCH k gt PCL interrupt 0 gt GLINTD b6kk RETLW k Return with literal in W k gt W TOS gt PC 3 unchanged 0002 RETURN Return from subroutine TOS gt PC 3 unchanged 33ff TSTFSZ Test f skip if zero skip if f 0 DS33014F page 138 O 1997 Microchip Technology Inc Appendix E Quick Reference Table E 16 PIC17CXX Special Co
47. AS E CODE ASM CODE HEX Programmer CPU a 609060 Figure 1 1 Generating Absolute Code MPASM also has the ability to generate an object module that can be linked with other modules using Microchip s MPLINK linker to form the final executable code This method is very useful for creating reusable modules that do not have to be retested each time they are used Related modules can also be grouped and stored together in a library using Microchip s MPLIB Librarian Required libraries can be specified at link time and only the routines that are needed will be included in the final executable A visual representation of this process follows O 1997 Microchip Technology Inc DS33014F page 5 MPASM USER S GUIDE with MPLINK and MPLIB LMI H A 1 I rao E B 2 TALE K i mE y Figure 1 2 Creating a Reusable Object Library wep ao I Figure 1 3 Generating Executable Code From Object Modules Refer to Chapter 4 Using MPASM to Create Relocatable Objects for more information on the differences between absolute and object assembly DS33014F page 6 O 1997 Microchip Technology Inc Chapter 1 Documentation Layout The documentation is intended to describe how to use the assembler and its environment It also provides some basic information about specific Microchip microcontrollers and their instruction sets but detailed discussion of these issues is deferred to the data sh
48. ASM USER S GUIDE with MPLINK and MPLIB Table E 6 PIC16C5X Byte Oriented File Register Operations Hex Mnemonic Description Function 1C ADDWF f d Add W and f W f gt d 14f ANDWF d AND W and f W AND f gt d 06f CLRF f Clear f 0 gt f 040 CLRW Clear W 0 W 24f COMF a Complement f NOT f gt d OCf DECF f d Decrement f f 1 gt d 2Cf DECFSZ da Decrement f skip if zero f 1 d skip if zero 28f INCF d Increment f f 1 gt d 3Cf INCFSZ f d Increment f skip if zero f 1 gt d skip if zero 10f TORWF f d Inclusive OR W and f W OR f gt d 20f MOVF f d Move f fod 02f MOVWF Move W tof wo f 000 NOP No operation 34f RLF d Rotate left f C Ted me 0 pub 30 RRF d Rotate right f register f eo gt Trono 0 08f SUBWF d Subtract W from f f W gt d 38 f SWAPF f d Swap halves f f 0 3 O 4 7 gt d 18f XORWF d Exclusive OR W and f W XOR f gt d Table E 7 PIC16C5X Bit Oriented File Register Operations Hex Mnemonic Description Function 4bf BCF b Bit clear f 0 gt f b 5bf BSF b Bit set f 1 gt f b 6bf BTFSC b Bit test skip if clear skip if f b 0 7bf BTFSS b Bit test skip if set Skip if f b 1 DS33014F page 132 O 1997 Microchip Technology Inc Appendix E Quick Reference
49. ATUS register will be generated For 14 bit and 16 bit core devices MOVLW and MOVWF instructions will be generated to modify the PCLATH If the device contains only one page of program memory no code will be generated For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example pagesel GotoDest goto GotoDest pagesel CallDest call CallDest See Also BANKSEL BANKISEL PROCESSOR Set Processor Type Syntax processor Xprocessor type Description Sets the processor type to processor type Example processor 16C54 See Also LIST RADIX Specify Default Radix Syntax radix default radix Description Sets the default radix for data expressions The default radix is nex Valid radix values are hex dec Or oct O 1997 Microchip Technology Inc DS33014F page 49 f mi gt S MPASM USER S GUIDE with MPLINK and MPLIB Example radix dec See Also LIST RES Reserve Memory Syntax 1abel res mem units Description Causes the program counter to be advanced from its current location by the value specified in mem units Note that 1abel will be installed as an address as opposed to a constant or variable Example buffer res 64 reserve 64 words of storage See Also ORG FILL SET Define an Assembler Variable Syntax label set lt expr gt Description lt label gt assumes the value of the val
50. BLE Declare Symbol Variable variable lt label gt lt expr gt lt label gt lt expr gt WHILE Perform Loop While Condition is True while lt expr gt O 1997 Microchip Technology Inc DS33014F page 25 f n gt i S MPASM USER S GUIDE with MPLINK and MPLIB Directive Details The remainder of this chapter is dedicated to providing a detailed description of the directives supported by MPASM Each definition will show Syntax Description Example _ _BADRAM Identify Unimplemented RAM Syntax _ _badram lt expr gt lt expr gt lt expr gt lt expr gt Description The _ _MAXRAM and _ _BADRAM directives together flag accesses to unimplemented registers _ _BADRAM defines the locations of invalid RAM addresses This directive is designed for use with the _ _MAXRAM directive A MAXRAM directive must preceed any _ BADRAM directive Each lt expr gt must be less than or equal to the value specified by _ _MAXRAM Once the __ MAXRAM directive is used strict RAM address checking is enabled using the RAM map specified by _ BADRAM Example See the example for _MAXRAM See Also MAXRAM BANKISEL Generate Indirect Bank Selecting Code Syntax bankisel label Description For use when generating an object file This directive is an instruction to the linker to generate the appropriate bank selecting code for an indirect access of the address specified by
51. DDEDEDDDDDDEOSESESLLLLLLELLLL LZ hE CELL CLORIZCPPPEGOLLLULLELIILNLEELLACCCOELCLELECELLLLLELIELLALLULOuIHrLIILTICEBSEBOLEL LCLLLLEECGCOLTLELUTIUTC LGEZOIHZILOLILLLLLULILL LUGLCHLOEU ES DS33014F page 34 1997 Microchip Technology Inc Description ENDC terminates the end of a CBLOCK list It must be supplied to terminate the list See Also CBLOCK ENDIF End Conditional Assembly Block Syntax endif Description Chapter 3 mi gt S This directive marks the end of a conditional assembly block ENDIF may be used inside a regular program block or macro See Also IF ELSE ENDM End a Macro Definition Syntax endm Description Terminates a macro definition begun with MACRO Example make table macro argl arg2 dw argl O0 null terminate table name res arg2 reserve storage endm See Also MACRO EXITM ENDW End a While Loop Syntax endw O 1997 Microchip Technology Inc DS33014F page 35 MPASM USER S GUIDE with MPLINK and MPLIB Description ENDW terminates a WHILE loop As long as the condition specified by the WHILE directive remains true the source code between the WHILE directive and the ENDW directive will be repeatedly expanded in the assembly source code stream This directive may be used inside a regular program block or macro Example See the example for WHILE See Also WHILE EQU Define an Assembler Constant Syntax label equ e
52. DW Unmatched ENDC ENDC found without a CBLOCK Unmatched ENDM ENDM found without a MACRO definition Unmatched EXITM EXITM found without a MACRO definition Directive not allowed when generating an object file The ORG directive is not allowed when generating an object file Instead declare a data or code section specifying the address if necessary Expanded source line exceeded 200 characters The maximum length of a source line after DEFINE and macro parameter substitution is 200 characters Note that DEFINE substitution does not include comments but macro parameter substitution does Directive only allowed when generating an object file section Certain directives such as GLOBAL and EXTERN only have meaning when an object file is generated They cannot be used when generating absolute code DS33014F page 112 O 1997 Microchip Technology Inc Appendix C MPASM Errors Warnings Messages 150 151 152 153 154 155 156 157 Warnings 201 202 Labels must be defined in a code or data section when making an object file When generating an object file all data and code address labels must be defined inside a data or code section Symbols defined by the EQU and SET directives can be defined outside of a section Operand contains unresolvable labels or is too complex When generating an object file operands must be of the form HIGH LOW relocatable address label gt lt offset gt
53. Directive Language Introduction This chapter describes the MPASM directive language Directives are assembler commands that appear in the source code but are not translated directly into opcodes They are used to control the assembler its input output and data allocation Many of the assembler directives have alternate names and formats These may exist to provide backward compatibility with previous assemblers from Microchip and to be compatible with individual programming practices If portable code is desired it is recommended that programs be written using the specifications contained within this document Highlights There are four basic types of directives provided by MPASM e Control Directives Data Directives Listing Directives Macro Directives Object File Directives Terms Control Directives Control directives permit sections of conditionally assembled code Data Directives Data Directives are those that control the allocation of memory and provide a way to refer to data items symbolically that is by meaningful names Listing Directives Listing Directives are those directives that control the MPASM listing file format They allow the specification of titles pagination and other listing control Macro Directives These directives control the execution and data allocation within macro body definitions Object File Directives These directives are used only when creating an object file
54. ED 7 BY USER PROGRAMS THIS CAN BE DONE BY DECLARING A SECTION WITH THE SAME NAME AND ATTRIBUTE i e VARIABLES UDATA OVER in MPASM pragma udata overlay VARIABLES in MPLAB C num init RES 2 Number of entries in init table init entry from addr RES 2 ROM address to copy const data from init entry to addr RES 2 RAM address to copy const data to init entry size RES 2 save tblptrl RES 1 save_tblptrh RES di Number of bytes in each init section These two variables preserve the position of TBLTRL within the entry table KKK KKK KKK KKK KK KKK KKK KK KK KKK KKK KK KKK KKK KKK KKK KK KKK KK KKK KKK kockckckckck _copy_idata_sec CODE PROGMEM_START 1997 Microchip Technology Inc DS33014F page 147 MPASM USER S GUIDE with MPLINK and MPLIB Copy initialized data from ROM to RAM KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KK KKK KK KKK KKK kockckckckok KKK KK KKK KKK KKK KKK KK KKK KKK KKK KKK KK KKK KKK KKK KKK kckckckckckckckck kckckck kockockckckok H The values to be stored in initialized data are stored in program memory sections The actual initialized variables are Stored in data memory in a section defined by the IDATA directive cn Such sections in a program Section where the data is to be copied from memory where the data is to be copied PASM or automatically defined by MPLAB C The table below has an entry for each H The startup cod
55. Greater or equal Operator Example Return program counter goto 3 Left Parenthesis 1 d 4 Right Parenthesis Length 1 256 Item NOT logical complement if a b Negation 2 s complement 1 Length Complement flags flags high Return high byte movlw high CTR Table low Return low byte movlw low CTR Table Multiply a b c Divide a b c Modulus entry len tot len 16 Add tot len entry len 8 1 Subtract entry len tot 1 8 Left shift flags flags 1 gt gt Right shift flags flags gt gt 1 if entry_idx gt num_entries gt Greater than if entry_idx gt num_entries Less than if entry_idx lt num_entries lt Less or equal if entry_idx lt num_entries Equal to if entry_idx num_entries Not equal to if entry_idx num_entries amp Bitwise AND flags flags ERROR BIT Bitwise exclusive OR flags flags ERROR_BIT Bitwise inclusive OR flags flags ERROR_BIT amp amp Logical AND if len 512 amp amp b c I Logical OR if len 512 b c Set equal to entry_index 0 Add to set equal entry_index 1 Subtract set equal entry_index 1 x Multiply set equal entry_index entry_length Divide set equal entry_total entry_length Modulus set equal entry_index 8 Left shift set equal fla
56. ITOIS o s in ue cue ei ue p DEREN AUR ile ees 109 lugere 113 Messages iio EM 116 MPLINK Errors Warnings Parse Errors ti A A A EIN NP WE 119 Linker EOS a A A Nc 120 Library FileErrOrS 3 uon C eo da ee Se eS 122 COFF File EPrOLS sco paige e t A ep ae n ie Een 123 COFF To COD Converter Errors 124 COFF To COD Converter Warnings ls 124 1997 Microchip Technology Inc DS33014F page vii MPASM USER S GUIDE with MPLINK and MPLIB Appendix E Appendix F Index Quick Reference Key to PICmicro Family Instruction Sets oo oooooomomoooo 131 PIC16C5X Instruction Set o o oooooococonnnn re 131 PIC16CXX Instruction Set o o ooooooococon ee eee eee 133 PIC17CXX Instruction Set 2 0 eee rh 136 Hexadecimal to Decimal Conversion 0000 0 eee eee 139 ASCII Character Set da a eee eens 140 Example Initialization Code Initialization Code oe cudei cee eee eee eens 141 Initialization Code for the PIC1I6CXX cee eee 141 Initialization Code for the PIC17CXX 1 cc eee 147 INdS Lx ente o Ra id 153 DS33014F page viii 1997 Microchip Technology Inc AN MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Part 1 MPASM Preface ocio A A ee ee ee E ER ee ene 3 Chapter 1 Introduction 2 4 scu sis ocyus haee 5 Chapter 2 Environment and Usage 20 cee eee eee eee eee 13 Chapter 3 Directive Language 2c cece eee eee eee eens 23 Chapter 4
57. Location Storage File call m 0x0026 program static C PROGRA 1 MPLAB ASMFOO sampobj asm loop 0x002e programstatic C MPASMV2 MUL8X8 ASM main 0x0024 programstatic C NPROGRA 1MMPLABNASMFOONsampob j asm mpy 0x0028 programextern C MPASMV2 MUL8X8 ASM start 0x0023 program static C NPROGRA 1MMPLABNASMFOONsampob j asm H byte 0x0022 data extern C MPASMV2 MUL8X8 ASM L byte 0x0023 data extern C MPASMV2NMMUL8X8 ASM count 0x0024 data static C MPASMV2 MUL8X8 ASM mulcnd 0x0020 data extern C MMPASMV2NMUL8X8 ASM mulplr 0x0021 data extern C MMPASMV2NMUL8X8 ASM O 1997 Microchip Technology Inc DS33014F page 89 MPASM USER S GUIDE with MPLINK and MPLIB The third table in the map file provides the same information that the second table provides but it is sorted by symbol address rather than symbol name The following is an example of the symbol table table sorted by address in a map file Symbols Sorted by Address Name Address Location Storage File start 0x0023 programstatic C PROGRA 1 MPLAB ASMFOO sampobj asm main 0x0024 programstatic C PROGRA 1 MPLAB ASMFOO sampobj asm call_m 0x0026 programstatic C PROGRA 1 MPLAB ASMFOO sampobj asm mpy 0x0028 programextern C MPASMV2 MUL8X8 ASM loop 0x002e programstatic C MPASMV2 MUL8X8 ASM mulcnd 0x0020 data extern C MMPASMV2NMUL8X8 ASM mulplr 0x0021 data extern C MPASMV2NMUL8X8 ASM H byte 0x0022 data extern C MPASMV2 MUL8X8 ASM L_byte 0x0023 data extern C MPASMV2NMUL8X8 ASM count
58. MPASM USER S GUIDE with MPLINK and MPLIB MPASM USER S GUIDE with MPLINK and MPLIB Information contained in this publication regarding device applications and the like is intended by way of suggestion only No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with re Spect to the accuracy or use of such information Use of Microchip s products as critical components in life support sys tems is not authorized except with express written approval by Microchip 1997 Microchip Technology Incorporated All rights reserved The Microchip logo name PIC PICMASTER PICSTART PRO MATE are registered trademarks of Microchip Technology Incorporated in the U S A and other countries MPLAB and PICmicro are trademarks of Microchip Technology in the U S A and other countries CompuServe is a registered trademark of CompuServe Incorporated IBM and PC AT are registered trademarks of International Business Machines Corporation Intel is a registered trademark of Intel Corporation Windows and MS DOS are registered trademarks of Microsoft Corporation All product company trademarks mentioned herein are the property of their respective companies 1997 Microchip Technology Inc DS33014F MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F O 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Table of Contents Preface Chapter 1 Cha
59. MPASM USER S GUIDE with MPLINK and MPLIB See Also LIST PROCESSOR __IDLOCS CONSTANT Declare Symbol Constant Syntax constant lt label gt lt expr gt lt label gt lt expr gt Description Creates symbols for use in MPASM expressions Contants may not be reset after having once been initialized and the expression must be fully resolvable at the time of the assignment This is the principal difference between symbols declared as CONSTANT and those declared as VARIABLE or created by the SET directive Otherwise constants and variables may be used interchangeably in expressions Example variable RecLength 64 Set Default E RecLength constant BufLength 512 Init BufLength RecLength may be reset later in RecLength 128 constant MaxMem RecLength BufLength CalcMaxMem See Also SET VARIABLE DATA Create Numeric and Text Data Syntax lt label gt data lt expr gt lt expr gt lt expr gt lt label gt data text string text string Description Initialize one or more words of program memory with data The data may be in the form of constants relocatable or external labels or expressions of any of the above The data may also consist of ASCII character strings text string enclosed in single quotes for one character or double quotes for strings Single character items are placed into the low byte of the word while strings DS33014F page 30 O 1997 Microchip Technology Inc
60. Modify this field the same as for the error file It is used to optionally disable the listing file The output file name may be modified as for the error file HEX Dump Type Set this value to generate the desired hex file format Changing this value is accomplished by moving to the field with the lt gt key and pressing the RET key to scroll through the available options To change the hex file name press the TAB key to move the shaded area and type in the new name Assemble to Object File Enabling this option will generate the relocatable object code that can be input to the linker and suppress generation of the hex file The file name may be modified in the same manner as the error file Windows Shell Interface MPASM for Windows provides an interface window which can set various options It is invoked by executing MPASMWIN EXE while in Windows MPASM vT 2 1409 Microchip Techno Inc Source File Name lc IMPASSE TESTSILOCAL ASI Options Radix Walia rary Land Ciarareisd Flea E eiut S Default fs Debut E Enu Fila C Hosdecmal T Al Moresqos C BRIM Uti Fl C Decimal T aminga ard Emaom T PHERS Cross Rafameocs Fila FP Orci T Emm ahy PORFA p ObgctFile Macro Expansion E Ceu Sonia Danh Procesor Doin n C oa Tab Sire 1997 Microchip Technology Inc DS33014F page 17 z pa gt 42 S MPASM USER S GUIDE with MPLINK and MPLIB When MPASM for Windows is invoked
61. NK combines multiple input object modules generated by MPLAB C or MPASM into a single executable file The actual addresses of data and the location of functions will be assigned when MPLINK is executed This means that you will instruct MPLINK to place code and data somewhere within named regions of memory not to specific physical locations y 9 A N U A Once the linker knows about the ROM and RAM memory regions available in the target PlCmicro device and it analyzes all the input files it will try to fit the application s routines into ROM and assign its data variables into available RAM If there is too much code or too many variables to fit MPLINK will give an error message MPLINK also provides flexibility for specifying that certain blocks of data memory are re usable so that different routines which never call each other and which don t depend upon this data to be retained between execution can share limited RAM space O 1997 Microchip Technology Inc DS33014F page 79 MPASM USER S GUIDE with MPLINK and MPLIB Libraries are available for most PICmicro peripheral functions as well as for many standard C functions The linker will only extract and link individual functions that are needed for the current application from the included libraries This means that relatively large libraries can be used in a highly efficient manner MPLINK combines all input files to generate the executable output and ens
62. NOLIST Turn off Listing Output Syntax nolist Description Turn off listing file output See Also LIST 1997 Microchip Technology Inc DS33014F page 47 MPASM USER S GUIDE with MPLINK and MPLIB ORG Set Program Origin Syntax lt label gt org lt expr gt Description Set the program origin for subsequent code at the address defined in lt expr gt If label is specified it will be given the value of the lt expr gt If no ORG is specified code generation will begin at address zero This directive may not be used when generating an object file Example int_1 org 0x20 Vector 20 code goes here int 2 org int 1 40x10 Vector 30 code goes here See Also RES FILL PAGE Insert Listing Page Eject Syntax page Description Inserts a page eject into the listing file See Also LIST TITLE SUBTITLE PAGESEL Generate Page Selecting Code Syntax pagesel label Description For use when generating an object file An instruction to the linker to generate page selecting code to set the page bits to the page containing the designated label Only one lt 1abe1 gt should be specified No operations can be performed on label label must have been previously defined DS33014F page 48 1997 Microchip Technology Inc Chapter 3 The linker will generate the appropriate page selecting code For 12 bit core devices the appropriate bit set clear instructions on the ST
63. PASM USER S GUIDE with MPLINK and MPLIB Relocatable Code Library Routine LIST P 16C54 INCLUDE P16C5x INC UDATA mulcnd RES 1 8 bit multiplicand mulplr RES 1 8 bit multiplier H_byte RES T High byte of the 16 bit result L_byte RES 1 Low byte of the 16 bit result count RES 1 loop counter GLOBAL mulcnd mulplr H byte L byte CODE mpy GLOBAL mpy clrf H byte clrt L byte moviw 8 movwf count movf muland W baf STATUS C Clear carry bit loop rx mulplr F btfsc STATUS E addwf H byte F rrf H_byte F frt L byte F decfsz count F goto loop retlw 0 END DS33014F page 64 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 5 Macro Language Introduction Macros are user defined sets of instructions and directives that will be evaluated in line with the assembler source code whenever the macro is invoked Macros consist of sequences of assembler instructions and directives They can be written to accept arguments making them quite flexible Their advantages are Higher levels of abstraction improving readability and reliability Consistent solutions to frequently performed functions Simplified changes Improved testability Applications might include creating complex tables frequently used code and complex operations Highlights The points that will be highlighed in this chapter are Macro Syntax Text Subs
64. R gt TBLAT addressed by table pointer TBLPTR 1 gt TBLPTR if i 1 acff TABLWT t i Write data from file f to table latch f gt TBLATH if t 1 and then write 16 bit table latch to f gt TBLATL if t 0 program memory location TBLAT gt ProgMem TBLPTR addressed bytable pointer TBLPTR 1 gt TBLPTR if i 1 a0ff TLRD t Read data from table latch into file f TBLATH f if t 1 table latch unchanged TBLATL gt f if t 0 a4ff TLWT t f Write data from file f into table latch f TBLATH if t 1 f gt TBLATL if t 0 Table E 13 PIC17CXX Arithmetic and Logical Instruction Hex Mnemonic Description Function b1kk ADDLW k Add literal to W W k gt W Oeff ADDWF f d Add W to F W f gt d 10ff ADDWFC d Add W and Carry to f W C gt d DS33014F page 136 O 1997 Microchip Technology Inc Appendix E Quick Reference Table E 13 PIC17CXX Arithmetic and Logical Instruction Continued Hex Mnemonic Description Function b5kk ANDLW k AND Literal and W W AND k gt W Oaff ANDWF f d AND W with f W AND f gt d 28ff CLRF d Clear f and Clear d 0x00 gt f 0x00 gt d 12ff COMF d Complement f NOT f gt d 2eff DAW f d Dec adjust W store in f d W adjusted f and d O6ff DECF d Decre
65. RED FERAE All rights reserved O 1997 Microchip Technology Incorporated USA 10 97 o Printed on recycled paper AREA AE IO Information contained in this publication regarding device applications and the like is intended for suggestion only and may be superseded by updates No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information or infringement of patents or other intellectual property rights arising from such use or otherwise Use of Microchip s products as critical components in life support systems is not authorized except with express written approval by Microchip No licenses are conveyed implicitly or otherwise under any intellectual property rights The Microchip logo and name are registered trademarks of Microchip Technology Inc in the U S A and other countries All rights reserved All other trademarks mentioned herein are the property of their respective companies D33014F page 156 O 1997 Microchip Technology Inc
66. SM Errors Warnings Messages A list of the error messages generated by MPASM with descriptions Appendix D MPLINK Errors Warnings 1997 Microchip Technology Inc DS33014F page 7 MPASM USER S GUIDE with MPLINK and MPLIB Terms Appendix E Quick Reference A concise listing of all instructions for the MPASM Assembler Appendix F Example Initialization Code Index A keyword cross reference to important topics and keywords Table 1 1 Documentation Conventions Character Represents Square Brackets Optional Arguments Angle Brackets Delimiters for special keys TAB lt ESC gt or additional options Pipe Character Choice of mutually exclusive arguments an OR selection Lowercase characters Type of data Courier Font User entered code or sample code In order to provide a common frame of reference the following terms are defined Assemble The act of executing the MPASM macro assembler to translate source code to machine code Directives Directives provide control of the assembler s operation by telling MPASM how to treat mnemonics define data and format the listing file Directives make coding easier and provide custom output according to specific needs Hex File This file contains the actual machine code that can be programmed into a microcontroller or memory device It is in a format that is readable by a device programmer Library
67. TECTED SHAREBANK NAME sfr START 0x300 END 0x30F PROTECTED SECTION Directive The following directive defines a section by specifying its name and either the block of program memory in ROM or the block of data memory in RAM which contains the section y 9 A N A SECTION NAME secName ROM memName RAM memName where secName is an ASCII string used to identify a SECTION this is the same name for the section in the COFF file memName is a previously defined SHAREBANK DATABANK or CODEPAGE The ROM attribute must always refer to program memory previously defined using a CODEPAGE directive The RAM attribute must always refer to data memory previously defined with a DATABANK or SHAREBANK directive 1997 Microchip Technology Inc DS33014F page 87 MPASM USER S GUIDE with MPLINK and MPLIB Example To specify that a section whose name is filter coeffs be loaded into the previously defined logical block of program memory named constants the following line should be added to the linker command file SECTION NAME filter coeffs ROM constants STACK Directive MPLAB C usually requires a software stack be set up The following statement specifies the stack size and an optional target memory where the stack is to be allocated STACK SIZE allocSize RAM memName where allocSize is the size in bytes of the stack and memName is the name of a memory
68. Technology Inc DS33014F page 103 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 104 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Appendix B On Line Support Introduction Microchip provides two methods of on line support These are the Microchip BBS and the Microchip World Wide Web WWW site Use Microchip s Bulletin Board Service BBS to get current information and help about Microchip products Microchip provides the BBS communication channel for you to use in extending your technical staff with microcontroller and memory experts To provide you with the most responsive service possible the Microchip systems team monitors the BBS posts the latest component data and software tool updates provides technical help and embedded systems insights and discusses how Microchip products provide project solutions The web site like the BBS is used by Microchip as a means to make files and information easily available to customers To view the site the user must have access to the Internet and a web browser such as Netscape or Microsoft Explorer Files are also available for FTP download from our FTP site Connecting to the Microchip Internet Web Site The Microchip web site is available by using your favorite Internet browser to attach to www microchip com The file transfer site is available by using an FTP service to connect to ftp ftp futureone co
69. Usage Command Eine oe Ske ae a Et ed ey 83 UsSage EXAmMple issi miira ann LeRR DUE MR a ah ee ee ed ees 84 Command File Directives couler PEE v ee A it A uEE 85 Linker Command File Example 0 0000 e eee eee 88 Linker Map File Linker Map File sig aie ee eee ee ee eee ee cs See eed SO he ete 89 Linker Processing Linker Allocation Algorithm 0 0 0 0 e eee eee 91 Relocation Example 0 0 cece eee eee eee eee 92 Initialized Data inicio 9I Se AAA EE UCR e 93 DS33014F page vi O 1997 Microchip Technology Inc Table of Contents Chapter 6 Chapter 1 Appendix A Appendix B Appendix C Appendix D Terminology Terminology sui la dia 95 Part 3 MPLIB Librarian Fundamentals Usage ui A A ee A E 99 Usage Examples coccion A be ee es 100 E RENA 100 Error Reporting sec cee teerien i ere r eue ne 100 Appendices Hex File Formats Introd ction 3o iere rem enu A Ng 101 AS e ert RE a Ma cete eto eon ege teh PR Rech d 101 Hex File Formats ors a aie 3er a aca X n ac s 101 On Line Support Introducir ica Bh ew elt EA ed Re es ee 105 Connecting to the Microchip Internet Web Site o o 105 Connecting to the Microchip BBS 2 0 0 cee eee 106 Using the Bulletin Board eee eae 106 Software Releases scs RR REGERE AE ERREUR 107 Systems Information and Upgrade Hot Line oo oooooooo o 108 MPASM Errors Warnings Messages E
70. Using MPASM to Create Relocatable Objects 57 Chapter 5 Macro Language 0c e eee eee eee nnn 65 Chapter 6 Expression Syntax and Operati0M o oooooooo 71 1997 Microchip Technology Inc DS33014F page 1 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 2 1997 Microchip Technology Inc MICROCHIP MPASM USER S GUIDE with MPLINK and MPLIB Preface Welcome Microchip Technology Incorporated is committed to providing useful and innovative solutions to your microcontroller designs MPASM is the first Universal Assembler available for Microchip s entire product line of microcontrollers MPASM will generate solid code with a directive language rich in potential Feature List and Product Information Migration Path MPASM provides a universal solution for developing assembly code for all of Microchip s 12 14 and 16 bit core PICmicro MCUs Notable features include All PlCmicro MCU Instruction Sets Command Line Interface Command Shell Interfaces Rich Directive Language e Flexible Macro Language MPLAB Compatibility Use of the Microchip MPASM Universal Assembler requires an IBM PC AT or compatible computer running MS DOS V5 0 or greater Since MPASM is a universal assembler for all PICmicro devices an application developed for the PIC16C54 can be easily translated into a program for the PIC16C71 This would require changing the instructio
71. W 006 TRIS Tristate port f W gt I O control reg f 3Akk XORLW k Exclusive OR literal and W k XOR W gt W Table E 9 PIC16CXX Byte Oriented File Register Operations Hex Mnemonic Description Function 07ff ADDWF f d Add W and f W f gt d O5ff ANDWF d AND W andf W AND f gt d 018f CLRF f Clear f 0 f 0100 CLRW Clear W 02 WwW 09ff COMF d Complement f NOT f gt d 03ff DECF d Decrement f f 1 gt d OBff DECFSZ da Decrement f skip if zero f 1 gt d skip if 0 OAff INCF d Increment f f riwvod 1997 Microchip Technology Inc DS33014F page 133 MPASM USER S GUIDE with MPLINK and MPLIB Table E 9 PIC16CXX Byte Oriented File Register Operations Hex Mnemonic Description Function OFff INCFSZ ad Increment f skip if zero f 1 gt d skip if 0 04ff TORWF d Inclusive OR W and f W OR f gt d 08ff MOVF f d Move f f gt d 008 MOVWF f Move W tof Wf 0000 NOP No operation ODff RLF a Rotate left f register f eo a ADA 0 OCff RRF d Rotate right f register f eo a du cw 0 02ff SUBWF d Subtract W from f f W d OEff SWAPF f d Swap halves f f 0 3 o 4 7 gt d O6ff XORWF d Exclusive OR W and f W XOR f gt d Table E 10 PIC16CXX Bit Oriented File Register Operations Hex Mnemonic Descrip
72. W instruction UU Example gt o dt A Message 0 lt dt FirstValue SecondValue EndOfValues See Also DATA DB DE DW DW Declare Data of One Word Syntax lt label gt dw lt expr gt lt expr gt lt expr gt Description Reserve program memory words for data initializing that space to specific values Values are stored into successive memory locations and the location counter is incremented by one Expressions may be literal strings and are stored as described in the DATA directive When generating an object file this directive can also be used to declare initialized data values Refer to the IDATA directive for more information Example dw 39 diagnostic 39 d_list 2 d_offset dw diagbase 1 See Also DATA DB IDATA ELSE Begin Alternative Assembly Block to IF Syntax else 1997 Microchip Technology Inc DS33014F page 33 MPASM USER S GUIDE with MPLINK and MPLIB Description Used in conjunction with an IF directive to provide an alternative path of assembly code should the IF evaluate to false ELSE may be used inside a regular program block or macro Example Speed macro rate LE rate lt 50 dw slow else dw fast endif endm See Also IF ENDIF END End Program Block Syntax end Description Indicates the end of the program Example start executable code end end of instructions ENDC End an Automatic Constant Block Syntax endc o iLLLOBEEARMASERESDSESEEEDES
73. Z Skip on Non Zero BTFSC 3 2 SKPZ Skip on Zero BTFSS 3 2 SUBCF f d Subtract Carry from File BTFSC 3 0 Z DECF f d SUBDCF f d Subtract Digit Carry from File BTFSC 3 1 Z DECF f d TSTF f Test File MOVF f 1 Z 1997 Microchip Technology Inc DS33014F page 135 MPASM USER S GUIDE with MPLINK and MPLIB PIC17CXX Instruction Set The PIC17CXX Microchip s high performance 8 bit microcontroller family uses a 16 bit wide instruction set The PIC17CXX instruction set consists of 55 instructions each a single 16 bit wide word Most instructions operate on a file register f and the working register W accumulator The result can be directed either to the file register or the W register or to both in the case of some instructions Some devices in this family also include hardware multiply instructions A few instructions operate solely on a file register BSF for example Table E 12 PIC17CXX Data Movement Instructions Hex Mnemonic Description Function 6pff MOVFP f p Moveftop fp b8kk MOVLB k Move literal to BSR k BSR 3 0 bakx MOVLP k Move literal to RAM page select k gt BSR 7 4 Apff MOVPF p f Movep to f pow 01ff MOVWE Move W to F Wf a8ff TABLRD t i f HRead data from table latch into file f TBLATH gt f if t 1 then update table latch with 16 bit TBLATL f if t 0 contents of memory location ProgMem TBLPT
74. able d not read symbol table d not read section header d not read raw data d not read line numbers d not read relocation info e filename for writing d not write file header d not write optional file header d not write section header O 1997 Microchip Technology Inc DS33014F page 123 MPASM USER S GUIDE with MPLINK and MPLIB Coff fi Coff fi Coff fi Coff fi Coff fi Coff fi e fi e fi e fi e fi e fi e fi ename cou ename cou ename cou ename cou ename cou ename cou d not write raw data d not write reloc d not write lineinfo d not write symbol d not write string table length d not write string COFF To COD Converter Errors Coff file filename must contain at least one code or romdata section In order to convert a COFF file to a COD file the COFF file must have either a code or a romdata section Could not open list file filename for writing Verify that if filename exists and that it is not a read only file COFF To COD Converter Warnings Could not open source file filename This file will not be present in the list file The referenced source file could not be opened This can happen if an input object library module was built on a machine with a different directory structure If source level debugging for the file is desired rebuild the object or library on the current machine DS33014F page 124 O 1997 Microchip Techn
75. age 1 RETLW 0 Relocatable Code LIST P 12C509 tinclude p12C509 INC Varl EQU H 10 Var2 EQU H 30 CODE OVLW InitialValue BANKSEL Varl OVWF Varl BANKSEL Var2 OVWF Var2 PAGESEL Subroutine CALL Subroutine Subroutine CLRW RETLW 0 O 1997 Microchip Technology Inc DS33014F page 61 MPASM USER S GUIDE with MPLINK and MPLIB Unavailable Directives Macro capability and nearly all directives are available when generating an object file The only directive that is not allowed is the ORG directive This can be replaced by specifying an absolute CODE segment as shown below Absolute Code Reset ORG H O1FF GOTO Start Relocatable Code Reset CODE H O1FF GOTO Start Generating the Object Module Once the code conversion is complete the object module is generated by requesting an object file on the command line or in the shell interface When using MPASM for Windows check the checkbox labeled Object File When using the DOS command line interface specify the o option When using the DOS shell interface toggle Assemble to Object File to Yes The output file will have a o extension Example The following is extracted from the example multiply routines given as a sample with MPASM Most of the comments have been stripped for brevity Absolute Code LIST P 16C54 INCLUDE P16C5x INC mulcnd EQU 09 8 bit multiplicand mulplr EQU 10 8 bit multiplier H_byte EQU 12 H
76. alue too large Last four hex digits used Only four hex digits are allowed for the ID locations Using default destination of 1 file If no destination bit is specified the default is used Crossing page boundary ensure page bits are set Generated code is crossing a page boundary Setting page bits Page bits are being set with the LCALL or LGOTO pseudo op Warning level superceded by command line value The warning level was specified on the command line as well as in the source file The command line has precedence Macro expansion superceded by command line Macro expansion was specified on the command line as well as in the source file The command line has precedence Superceding current maximum RAM and RAM map The MAXRAM directive has been used previously Operand of HIGH operator was larger than H FFFF The HIGH operator will return the value of the bits 8 through 15 of the operator shifted down to the lower byte Any bits above bit 15 are ignored The expression HIGH H 123456 evaluates to H 34 Page or Bank selection not needed for this device No code generated If a device contains only one ROM page or RAM bank no page or bank selection is required and any PAGESEL BANKSEL or BANKISEL directives will not generate any code DS33014F page 116 O 1997 Microchip Technology Inc Appendix C MPASM Errors Warnings Messages 313 CBLOCK constants will start with a value of 0 If the first
77. and all code between the EXITM and the ENDM directives for this macro to be ignored If macros are nested EXITM causes code generation to return to the previous level of macro expansion Examples Eight by Eight Multiply subtitle macro definitions page multiply eight by eight multiply macro executing in program memory optimized for speed straight line code written for the PIC17C42 multiply macro argl arg2 dest hi dest lo local i 0 establish local index variable and initialize it movlw argl setup multiplier movwf mulplr movlw arg2 setup multiplicand in w reg Glrtf dest hi Clear the destination regs clrf dest lo x bcf carry Clear carry for test while i lt 8 do all eight bits addwf dest hi then add multiplicand rrot dest hi shift right through carry rrcf dest lo shift right again snag carry if set by previous rotate i 1 increment loop counter endw break after eight iterations endm end of macro The macro declares all of the required arguments In this case there are four The LOCAL directive then establishes a local variable i that will be used as an index counter It is initialized to zero DS33014F page 68 O 1997 Microchip Technology Inc Chapter 5 A number of assembler instructions are then included When the macro is executed these instructions will be written in line with the rest of the assembler source code The macro writes the multiplicati
78. ant Block endc FILL Specify Memory Fill Value fill lt expr gt count IDLOCS Set ID locations idlocs lt expr gt RES Reserve Memory res mem units DS33014F page 126 O 1997 Microchip Technology Inc Appendix E Quick Reference Table E 1 MPASM Directive Language Summary Continued Directive Description Syntax MACROS ENDM End a Macro Definition endm EXITM Exit from a Macro exitm EXPAND Expand Macro Listing expand LOCAL Declare Local Macro Variable local lt label gt lt label gt MACRO Declare Macro Definition lt label gt macro lt arg gt lt arg gt NOEXPAND Turn off Macro Expansion noexpand OBJECT FILE DIRECTIVES section BANKISEL Generate RAM bank selecting code for bankisel lt label gt indirect addressing BANKSEL Generate RAM bank selecting code banksel lt label gt CODE Begins executable code section lt name gt code lt address gt EXTERN Declares an external label extern lt label gt lt label gt GLOBAL Exports a defined label extern label lt label gt IDATA Begins initialized data section lt name gt idata lt address gt PAGESEL Generate ROM page selecting code pagesel lt label gt UDATA Begins uninitialized data section lt name gt udata lt address gt UDATA_OVR Begins overlayed uninitialized data lt name gt udata_ovr lt address gt section UDATA_SHR Begins shared
79. as not Been ifndef label Defined INCLUDE Include Additional Source File include lt lt include_file gt gt lt include_file gt LIST Listing Options list list option list option LOCAL Declare Local Macro Variable local lt label gt lt label gt MACRO Declare Macro Definition label macro lt arg gt lt arg gt MAXRAM Specify maximum RAM address maxram lt expr gt MESSG Create User Defined Message messg lt message_text gt NOEXPAND Turn off Macro Expansion noexpand NOLIST Turn off Listing Output nolist ORG Set Program Origin lt label gt org lt expr gt PAGE Insert Listing Page Eject page PAGESEL Generate ROM page selecting code pagesel lt label gt PROCESSOR Set Processor Type processor lt processsor_type gt RADIX Specify Default Radix radix lt default_radix gt RES Reserve Memory lt label gt res lt mem_units gt SET Define an Assembler Variable lt label gt set lt expr gt SPACE Insert Blank Listing Lines space lt expr gt SUBTITLE Specify Program Subtitle subtitle lt sub_text gt TITLE Specify Program Title title lt title_text gt UDATA Begins uninitialized data section lt name gt udata lt address gt UDATA OVR Begins overlayed uninitialized data lt name gt udata ovr lt address gt section UDATA SHR Begins shared uninitialized data lt name gt udata_shr lt address gt section UNDEFINE Delete a Substitution Label undefine lt label gt VARIA
80. assigned So the following types of allocations exist 1 Absolute Assigned 2 Absolute Unassigned 3 Relocatable Assigned 4 Relocatable Unassigned 1997 Microchip Technology Inc DS33014F page 91 MPASM USER S GUIDE with MPLINK and MPLIB The linker performs allocation of absolute sections first followed by relocatable assigned sections followed by relocatable unassigned sections Absolute Allocation Absolute sections may be assigned to target memory blocks in the linker command file But since the absolute section s address is fixed the linker can only verify that if there is an assigned target memory block for an absolute section the target memory block has enough space and the absolute section does not overlap other sections If no target memory block is assigned to an absolute section the linker tries to find the one for it If one can not be located an error is generated Since absolute sections can only be allocated at a fixed address assigned and unassigned sections are performed in no particular order Relocatable Allocation Once all absolute sections have been allocated the linker allocates relocatable assigned sections For relocatable assigned sections the linker checks the assigned target memory block to verify that there is space available otherwise it s an error The allocation of relocatable assigned sections occurs in the order in which they were specified in the linker command file Afte
81. be a valid MPASM label The symbol named is removed from the symbol table Example define length20 undefine length See Also DEFINE IFDEF INCLUDE IFNDEF VARIABLE Declare Symbol Variable Syntax variable lt label gt lt expr gt lt label gt lt expr gt Description Creates symbols for use in MPASM expressions Variables and constants may be used interchangeably in expressions The VARIABLE directive creates a symbol that is functionally equivalent to those created by the SET directive The difference is that the VARIABLE directive does not require that symbols be initialized when they are declared Note that variable values cannot be updated within an operand You must place variable assignments increments and decrements on separate lines DS33014F page 54 1997 Microchip Technology Inc Chapter 3 Example Please refer to the CONSTANT example See Also SET CONSTANT WHILE Perform Loop While Condition is True mi gt S Syntax while lt expr gt endw Description The lines between the WHILE and the ENDW are assembled as long as lt expr gt evaluates to TRUE An expression that evaluates to zero is considered logically FALSE An expression that evaluates to any other value is considered logically TRUE A relational TRUE expression is guaranteed to return a non zero value FALSE a value of zero A WHILE loop can contain at most 100 lines and
82. be repeated a maximum of 256 times Example test_mac macro count variable i i 0 while i lt count movlw i i 1 endw endm start test mac 5 end See Also ENDW IF 1997 Microchip Technology Inc DS33014F page 55 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 56 O 1997 Microchip Technology Inc MICROCHIP Chapter 4 Using MPASM to Create Relocatable Objects Introduction Highlights Header Files MPASM USER S GUIDE with MPLINK and MPLIB With the introduction of MPASM v2 00 and MPLINK v1 00 users have the ability to generate and link precompiled object modules Writing source code that will be assembled to an object module is slightly different from generating executable code directly to a hex file Existing MPASM routines will require minor modifications to compile correctly into relocatable object modules Use of Header Files Program Memory Definition Instruction Operands RAM Allocation Configuration Bits and ID Locations Accessing Labels from Other Modules Paging and Banking Issues Unavailable Directives Generating the Object Module Code Example The Microchip supplied standard header files should be used when generating object modules These header files define the special function registers for the target processor Program Memory Program memory code must be preceded by a CODE section declaration Absolute Code Start CLRW OPTION Re
83. bout the argument The EXTERN directive should only be used when making a O file The EXTERN directive only has meaning if an object file is being created This warning has been superceded by Error 149 Unmatched An unmatched parenthesis was found The warning is used if the parenthesis is not used for indicating order of evaluation Processor superceded by command line Verify processor symbol The processor was specified on the command line as well as in the source file The command line has precedence DS33014F page 114 O 1997 Microchip Technology Inc Appendix C MPASM Errors Warnings Messages 216 217 218 219 220 221 222 223 224 225 226 Radix superceded by command line The radix was specified on the command line as well as in the source file The command line has precedence Hex file format specified on command line The hex file format was specified on the command line as well as in the source file The command line has precedence Expected DEC OCT HEX Will use HEX Bad radix specification Invalid RAM location specified Ifthe MAXRAM and __BADRAM directives are used this warning flags use of any RAM locations declared as invalid by these directives Note that the provided header files include __MAXRAM and BADRAM for each processor Address exceeds maximum range for this processor A ROM location was specified that exceeds the processor s memory size Inva
84. ces MOVLB or MOVLR will be generated If the device contains only one bank of RAM no instructions will be generated For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example banksel Varl movwf Varl O 1997 Microchip Technology Inc DS33014F page 27 MPASM USER S GUIDE with MPLINK and MPLIB See Also PAGESEL BANKISEL CBLOCK Define a Block of Constants Syntax cblock lt expr gt lt label gt lt increment gt lt label gt lt increment gt ende Description Define a list of named constants Each lt label gt is assigned a value of one higher than the previous 1abel The purpose of this directive is to assign address offsets to many labels The list of names end when an ENDC directive is encountered expr indicates the starting value for the first name in the block If no expression is found the first name will receive a value one higher than the final name in the previous CBLOCK If the first CBLOCK in the source file has no lt expr gt assigned values start with zero If lt increment gt is specified then the next 1abe1 is assigned the value of increment higher than the previous 1abel Multiple names may be given on a line separated by commas Example cblock 0x20 name 1 will be assigned 20 name 1 name 2 name 2 21 and so on name 3 name 4 name 4 is assigned 23 endc cblock 0x30 TwoByteVar 0 TwoByteHigh TwoByteLow
85. d to reserve space for data mi gt S For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example Temps udata_ovr Temp1 res 1 Temp2 res 1 Temp3 res 1 Temps udata ovr LongTempl res 2 LongTemp2 res 2 See Also TEXT IDATA UDATA EXTERN GLOBAL UDATA_SHR UDATA_SHR Begin an Object File Shared Uninitialized Data Section Syntax lt label gt udata_shr lt RAM address gt Description For use when generating an object file Declares the beginning of a section of shared uninitialized data If lt 1abe1 gt is not specified the section is named udata_shr The starting address is initialized to the specified address or zero if no address is specified This directive is used to declare variables that are allocated in RAM that is shared across all RAM banks i e unbanked RAM No code can be generated in this segment The RES directive should be used to reserve space for data For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects 1997 Microchip Technology Inc DS33014F page 53 MPASM USER S GUIDE with MPLINK and MPLIB Example Temps udata shr Tempi res 1 Temp2 res I Temp3 res T See Also TEXT IDATA UDATA EXTERN GLOBAL UDATA OVR FUNDEFINE Delete a Substitution Label Syntax tundefine lt label gt Description label is an identifier previously defined with the DEF INE directive lt must
86. e below walks the table addresses and counts _cinit DS33014F page 148 There are num init Each entry contains the starting address in program memory the starting address in data and the number of bytes to copy reading those starting and copies the data from program to data memory SS num_init low 4 num_init high init_entry_from_addr low 4 2 init_entry_from_addr high ql sit ete e EF L init_entry_to_addr low init_entry_to_addr high 4 init_entry_size low 4 init_entry_size high eec init_entry_from_addr low pce AP APA init entry from addr high 4 init_entry_to_addr low 4 init_entry_to_addr high pers A MU CPU RE L init_entry_size low 4 init_entry_size high tes IDATA 0 IDATA num init 1 O 1997 Microchip Technology Inc Appendix F Example Initialization Code Start of code that copies initialization data from program to data memory copy init data H First read the count of entries cinit moviw HIGH cinit movwf PCLATH CALL _cinit Ox3FF BANKSEL num init movwf num init CALL cinit Ox3FF 1 movwf num init 1 gt For num_init do co
87. e counter for the outermost loop no of init secs dec num init decf num init l1 btfss ALUSTA C decf num_init 1 1 Now restore TBLPTRH TBLPTRL to point to table movfp save tblptrl WREG movwf TBLPTRL movfp save tblptrh WREG movwf TBLPTRH Ihen go back to the top to do the next section if any goto loop num init We re done copying initialized data end copy init data return Must declare it as GLOBAL to be able to call it from other assembly modules GLOBAL copy init data END e a eee DS33014F page 152 1997 Microchip Technology Inc hy MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Index Symbols E Initialization 141 DEFINE 32 42 54 109 112 ELSE 33 41 42 RUE Mesue in UNDEFINE 42 54 END PI Xx PROLES LE ENDC C16C eiecit ideae Roos 133 A ENDIF PIC17OXX 136 Arithmatic Operators 75 130 ENDM Special Instructions 134 Assemble s 8 ENDW mernet i EQU Connecting to Microchip B ERROR web site 105 BADRAM 26 46 115 error file 14 20 22 37 109 Internet Home Page ETE 11 BANKISEL 26 1133 uu 119 128 L BANKSEL e ERRORLEVEL 37 115 Labels 19 BOBS ocio Escape Sequences IA 73 AN EN O 8 application notes EXTM E a 37 66 68 112 E A te
88. e must be allocated in a data section Three types of data sections are available UDATA Uninitialized data This is the most common type of data section Locations reserved in this section are not initialized and can be accessed only by the labels defined in this section or by indirect accesses DS33014F page 58 O 1997 Microchip Technology Inc Chapter 4 UDATA_OVR Uninitialized overlayed data This data section is used for variables that can be declared at the same address as other variables in the same module or in other linked modules A typical use of this section is for temporary variables UDATA SHR Uninitialized shared data This data section is used for variables that will be placed in RAM that is unbanked or shared across all banks f n gt S IDATA Initialized data The linker will generate a look up table that can be used to initialize the variables in this section to the specified values The locations reserved by this section can be accessed only by the labels defined in this section or by indirect accesses The following example shows how a data declaration might be created Absolute Code CBLOCK 0x20 InputGain OutputGain Control loop gains HistoryVector Must be initialized to 0 Templ Temp2 Temp3 Used for internal calculations ENDC Relocatable Code IDATA HistoryVector DB 0 UDATA InputGain RES 1 OutputGain RES UDATA_OVR Templ RES 1 Temp2 RES 1 Te
89. e the end of the line the string will end at the end of the line While there is no direct provision for continuation onto a second line it is generally no problem to use a second Dw directive for the next line The pw directive will store the entire string into successive words If a string has an odd number of characters bytes the bw and DATA directives will pad the end of the string with one byte of zero 00 If a string is used as a literal operand it must be exactly one character long or an error will occur See the examples below for the object code generated by different statements involving strings 7465 7374 696E dw testing output string one n 6720 6F75 7470 7574 2073 7472 696E 6720 6F6E 650A define str testing output string two B061 moviw a 7465 7374 696E data testing first output string 6720 6669 7273 7420 6F75 7470 7574 2073 7472 696E 6700 DS33014F page 72 O 1997 Microchip Technology Inc Chapter 6 The assembler accepts the ANSI C escape sequences to represent certain 8 special control characters Table 6 1 ANSI C Escape Sequences Escape Description Hex U Character Value gt o a Bell alert character 07 b Backspace character 08 f Form feed character 0C in New line character 0A r Carriage return character 0D X Horizontal tab character 09 v Vertical tab character 0B Backslash 5C
90. eces This error is very rare and will only occur in source code that references addresses above 32K including configuration bits Call or jump not allowed at this address A call or jump cannot be made to this address For example CALL destinations on the PIC16C5x family must be in the lower half of the page DS33014F page 110 O 1997 Microchip Technology Inc Appendix C MPASM Errors Warnings Messages 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 Illegal label Labels are not allowed on certain directive lines Simply put the label on its own line above the directive Also HIGH LOW PAGE and BANK are not allowed as labels Illegal opcode Token is not a valid opcode Illegal directive Directive is not allowed for the selected processor for example the IDLOCS directive on the PIC17C42 Illegal argument An illegal directive argument for example LIST STUPID Illegal condition A bad conditional assembly For example an unmatched ENDIF Argument out of range Opcode or directive argument out of the valid range for example TRIS 10 Too many arguments Too many arguments specified for a macro call Missing argument s Not enough arguments for a macro call or an opcode Expected Expected a certain type of argument The expected list will be provided Processor type previously defined A different family of processor is being selec
91. ect files K pathlist semi colon delimited list of directories to search for linker command files n length number of lines per listing page 0 no pagination hy show this help screen a lt hexformat gt specify format of hex programming file Valid formats are INHX8M INHX8S INHX32 q quiet mode operation There is no required order for the command line arguments however changing the order can affect the operation of the linker Specifically additions to the library object directory search path are appended to the end of the current library object directory search path as they are encountered on the command line and in command files O 1997 Microchip Technology Inc DS33014F page 83 U e A N UU A MPASM USER S GUIDE with MPLINK and MPLIB Library and object files are searched for in the order in which directories occur in the library object directory search path Therefore changing the order of directories may change which file is selected The o option is used to supply the name of the generated output COFF file The linker also generates a COD file for MPLAB debugging and an Intel format HEX programming Both of these files have the same name as the output COFF file but with the file extensions cod and hex respectively If the o option is not supplied the default output COFF file is named a out and the corresponding COD and HEX files are
92. ect of turning listing output on if it had been previously turned off Otherwise one of the following list options can be supplied to control the assembly process or format the listing file Table 3 2 List Directive Options Option Default Description b nnn 8 Set tab spaces c nnn 132 Set column width f format INHX8M Set the hex file output format can be INHX32 INHX8M or INHX8S free FIXED Use free format parser Provided for backward compatibility fixed FIXED Use fixed format parser mm ON OFF On Print memory map in list file n nnn 60 Set lines per page p lt type gt None Set processor type for example PIC16C54 r lt radix gt hex Set default radix hex dec oct st ON OFF On Print symbol table in list file t ON OFF Off Truncate lines of listing otherwise wrap w 0 1 2 0 Set the message level See ERRORLEVEL x ON OFF On Turn macro expansion on or off Note All LIST options are evaluated as decimal numbers Example list p 17c42 f INHX32 r DEC See Also NOLIST PROCESSOR RADIX ERRORLEVEL EXPAND NOEXPAND LOCAL Declare Local Macro Variable Syntax local lt label gt lt label gt DS33014F page 44 O 1997 Microchip Technology Inc Chapter 3 Description Declares that the specified data elements are to be considered in local context to the macro 1abel may be identical to another label declared outside the
93. eets for specific microcontrollers Part 1 MPASM Chapter 1 Introduction Introduces the user to MPASM It describes the User s Guide layout general conventions and terms as well as a brief discussion of installation and platform requirements f n gt Chapter 2 Environment and Usage This chapter describes the assembler s command line interface and shell interface Also discussed here are the files used by MPASM both input and output including object file formats Chapter 3 Directive Language This chapter describes the native directive language of MPASM Chapter 4 Using MPASM to Create Relocatable Objects Information on the differences between absolute and object assembly Chapter 5 Macro Language This chapter describes the macro language of MPASM Macros are best learned by example several will be offered for consideration Chapter 6 Expression Syntax and Operation This chapter describes the expression syntax of MPASM including operator precedence radix override notation examples and discussion Part 2 MPLINK Chapter 1 Introduction Chapter 2 Usage Chapter 3 Command File Chapter 4 Linker Map File Chapter 5 Linker Processing Chapter 6 Terminology Part 3 MPLIB Chapter 1 Librarian Fundamentals Appendix A Hex File Formats A brief reference Appendix B On Line Support Information on Microchip s electronic support services Appendix C MPA
94. er than if entry_idx gt num_entries lt Less than if entry_idx lt num_entries lt Less or equal if entry_idx lt num_entries Equal to if entry_idx num_entries l Not equal to if entry_idx num_entries amp Bitwise AND flags flags amp ERROR_BIT Bitwise exclusive OR flags flags ERROR BIT Bitwise inclusive OR flags flags ERROR BIT amp amp Logical AND if len 512 amp amp b c Il Logical OR if len 512 b c Set equal to entry_index 0 Add to set equal entry_index 1 I Subtract set equal entry index 1 Multiply set equal entry_index entry_length l Divide set equal entry_total entry_length Modulus set equal entry_index 8 lt lt Left shift set equal flags lt lt 3 gt gt Right shift set equal flags gt gt 3 amp AND set equal flags amp ERROR_FLAG Inclusive OR set equal flags ERROR_FLAG A Exclusive OR set equal flags ERROR FLAG Increment i Decrement i DS33014F page 130 O 1997 Microchip Technology Inc Appendix E Quick Reference Key to PlCmicro Family Instruction Sets Field Description b Bit address within an 8 bit file register d Destination select d 0 Store result in W f0A d 1 Store result in file register f Default is d 1 f Register file address 0x00 to OxFF k Literal field constant data or label WwW Working register accum
95. erated by MPLAB C to handle the function s entry and exit 0x0000 MOVLW OxFF 0x0001 MOVLR Need to patch with varl s bank 0x0002 MOVWE Need to patch with varl s offset When the compiler processes source line 1 it creates a symbol table entry for the identifier var1 which has the following information Symbol index gt name varl value 0 section data class extern When the compiler processes source line 3 it generates two relocation entries in the code section for the identifier symbol var1 since its final address is unknown until link time The relocation entries have the following information Reloc index address 0x0001 symbol varl type bank Reloc index gt address 0x0002 symbol varl type offset Once the linker has placed every section into target memory the final addresses are known Once all identifier symbols have their final addresses assigned the linker must patch all references to these symbols using the relocation entries In the example above the updated symbol might now be at location 0x125 Symbol index gt name varl value 0x125 section data class extern If the code section above were relocated to begin at address 0x50 the updated relocation entries would now begin at location 0x51 Reloc index gt address 0x0051 symbol varl type bank Reloc index gt address 0x0052 symbol varl type offset y 9 A N U A The linker will step through the relocation entries and
96. et eee cesed bug reports EXPAND ene LIST Connecting to Expressions listing 37 psc isting seseeesee ara pecas E EXTERN eene listing file 9 14 17 20 21 23 38 source code AR 407 Foo rn 44 47 51 52 f LOCAL 44 68 Special Interest Groups 107 File Local tabel 66 Systems Information cross reference 15 16 pem PESE MY and Upgrade Ades um ggg LOW eererseeeeean Hot Line 108 listing 14 17 M Using the 106 object re 14 MACRO a 14 35 45 C fil SOUL GES rendie aena Bs Macro ici 9 65 CAU pe 110 d zi 39 MAXRAM sess 26 46 115 116 HEE E OS a S E HUE E message level 15 18 37 44 CBLOCK 22 28 35 110 G MESS cocine mice 47 CODE A e LA a 29 GLOBAL gu Migration Path ratico eee 29 GLOBAL Lise Mnemonics E C dL Interf 13 14 A a 128 H MPASM eeerenne IT uM A Nr ree MPASMWIN 14 17 109 Compatibility 10 Hex File iei CONFIG sse 29 hex file format 14 17 20 MPLINK CONSTANT 29307 HIGH cte 1131 MPLINK 1e 9 cross reference file 15 High LOW iio torito 76 N D l NOEXPAND NOLIST ien O Define coccion dde MEDEL cade aeia Directives o ata ce B IFNDEEB s etica HO a INCLUDE Operators A A s s 76 ORG ioi es O 1997 Microchip Technology Inc DS33014F page 153 MPASM USER S GUIDE w
97. file File for writing Verify that if File exists it is not a read only file Library File Errors Symbol name has multiple external definitions A symbol may only be defined once in a library file Could not open library file filename for reading Verify that filename exists and can be read Could not read archive magic string in library file filename The file is not a valid library file or it may be corrupted File filename is not a valid library file Library files must end with Llib Library file filename has a missing member object file The file not a valid object file or it may be corrupted Could not build member memberName in library file filename The file is not a valid library file or it is corrupted Could not open library file filename for writing Verify that if filename exists it is not read only Could not write archive magic string in library file filename The file may be corrupted Could not write member header for memberName in library file filename The file may be corrupted DS33014F page 122 1997 Microchip Technology Inc Appendix D MPLINK Errors Warnings memberName is not a member of filename nemberName can not be extracted or deleted from a library unless it is a member of the library COFF File Errors All COFF file errors indicate an internal error in the file s contents Please contact Microchip support if an
98. gh Low and Increment Decrement Operators Terms Expressions Expressions are used in the operand field of the source line and may contain constants symbols or any combination of constants and symbols separated by arithmetic operators Each constant or symbol may be preceded by a plus or minus to indicate a positive or negative expression Note Expressions are evaluated in 32 bit integer math floating point is not currently supported Operators Operators are arithmetic symbols like the plus sign and the minus sign that are used when forming well defined expressions Each operator has an assigned precedence Precedence Precedence is the concept that some elements of an expression get evaluated before others Operators of the same precedence are evaluated from left to right Radix Radix is the base numbering system that the assembler uses when evaluating expressions The default radix is hexadecimal base 16 You can change the default radix See Chapter 3 and override the default radix with certain radix override operators O 1997 Microchip Technology Inc DS33014F page 71 MPASM USER S GUIDE with MPLINK and MPLIB Text Strings A string is a sequence of any valid ASCII character of the decimal range of 0 to 127 enclosed by double quotes Strings may be of any length that will fit within a 255 column source line If a matching quote mark is found the string ends If none is found befor
99. gram memory the initializer section begins where in data memory the initialized data section begins and how many bytes are in the initialized data section The boot code accesses this table and copies the data from ROM to RAM DS33014F page 94 1997 Microchip Technology Inc MICROCHIP MPASM USER S GUIDE with MPLINK and MPLIB Chapter 6 Terminology Terminology Absolute Section Assigned Section COD COFF Identifier External Linkage External Symbol External Symbol Definition External Symbol Reference External Symbol Resolution Hex File Initialized Data Internal Linkage A section with a fixed absolute address which can not be changed by the Linker A section which has been assigned to a target memory block in the linker command file The Linker allocates an assigned section into its assigned target memory block Common Object Description a file format definition for executable files created by Byte Craft Limited of Waterloo Canada Common Object File Format a file format definition for object executable files A function or variable name A function or variable has external linkage if it can be accessed from outside the module in which it is defined A symbol for an identifier which has external linkage An external symbol for a function or variable defined in the current module U 9 A N U A An external symbol which references a functio
100. gs lt lt 3 gt gt Right shift set equal flags gt gt 3 amp AND set equal flags amp ERROR FLAG Inclusive OR set equal flags ERROR FLAG Exclusive OR set equal flags ERROR FLAG O 1997 Microchip Technology Inc DS33014F page 75 f n gt S MPASM USER S GUIDE with MPLINK and MPLIB High Low Syntax high lt operand gt low lt operand gt Description The high operators are used to return the high byte or the low byte of a 16 bit label value This is done to handle dynamic pointer calculations as might be used with table read and write instructions Example movlw low size handle the 1sb s movpf wreg low size lo moviw high size handle the msb s movpf wreg high size hi Increment Decrement Syntax lt variable gt lt variable gt Description Increments or decrements a variable value These operators can only be used on a line by themselves they cannot be embedded within other expression evaluation Example LoopCount 4 while LoopCount gt 0 rlf Reg f LoopCount endw DS33014F page 76 O 1997 Microchip Technology Inc AN MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Part 2 MPLINK Chapter 1 Introduction lt lt lt oe nha nnn RR 79 Chapter2 Usage ss vos ae eee eae a wae a eee ee 83 Chapter 3 Command File 00 eee eee eee eens 85 Chapter 4 Linker Map
101. hould first be directed to your distributor and representative local sales office Field Application Engineer FAE or Corporate Applications Engineer CAE The Microchip Internet Home Page can provide you with technical information application notes and promotional news on Microchip products and technology The Microchip Web address is http www microchip com You can also check with the Microchip BBS Bulletin Board System for non urgent support customer forums and the latest revisions of Microchip systems development products Refer to Appendix B for access information mi gt S 1997 Microchip Technology Inc DS33014F page 11 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 12 1997 Microchip Technology Inc MICROCHIP MPASM USER S GUIDE with MPLINK and MPLIB Chapter 2 Environment and Usage Introduction Highlights Terms MPASM provides a universal platform for developing code for PICmicro MCUs This chapter is dedicated to describing the MPASM command line interface and the MPASM shells The points that will be highlighted in this chapter are MPASM Command Line Interface MPASM Shell Interfaces MPASM Input Files MPASM Output Files Alpha Character Alpha characters are those characters regardless of case that are normally contained in the alphabet a b z A B Z Alpha Numeric Alpha numeric characters incl
102. ialization codes for various PICmicro families Note that this directive is not available for 12 bit core devices The RES DB and DW directives may be used to reserve space for variables RES will generate an initial value of zero DB will initialize successive bytes of RAM DW will initialize successive bytes of RAM one word at a time in low byte high byte order For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example idata LimitL dw 0 LimitH dw D 300 Gain dw Dre Flags db 0 String db Hi there See Also TEXT UDATA UDATA OVR UDATA SHR EXTERN GLOBAL DS33014F page 40 1997 Microchip Technology Inc Chapter 3 f IDLOCS Set Processor ID Locations Syntax _ _idlocs lt expr gt un gt Description o z Sets the four ID locations to the hexadecimal digits of the value of lt expr gt For example if expr evaluates to 1AF the first lowest address ID location is zero the second is one the third is ten and the fourth is fifteen Before this directive is used the processor must be declared through the command line the LIST directive or the PROCESSOR directive This directive is not valid for the PIC17CXX family Example _ idlocs H 12 34 See Also LIST PROCESSOR CONFIG IF Begin Conditionally Assembled Code Block Syntax if lt expr gt Description Begin execution of a conditional assembly block If lt expr gt evaluates t
103. id MPASM expression specified by lt expr gt The SET directive is functionally equivalent to the EQU directive except that SET values may be subsequently altered by other SET directives Example area set 0 width set 0x12 length set 0x14 area set length width DS33014F page 50 O 1997 Microchip Technology Inc SPACE Insert Blank Listing Lines Chapter 3 length set length 1 See Also EQU VARIABLE f mi gt S Syntax space lt expr gt Description Insert lt expr gt number of blank lines into the listing file Example space 3 Inserts three blank lines See Also LIST SUBTITLE Specify Program Subtitle Syntax subtitle sub text Description sub text is an ASCII string enclosed in double quotes 60 characters or less in length This directive establishes a second program header line for use as a subtitle in the listing output Example subtitle diagnostic section See Also TITLE TITLE Specify Program Title Syntax title title text O 1997 Microchip Technology Inc DS33014F page 51 MPASM USER S GUIDE with MPLINK and MPLIB Description title text isa printable ASCII string enclosed in double quotes It must be 60 characters or less This directive establishes the text to be used in the top line of each page in the listing file Example title operational code rev 5 0 See Also LIST SUBTITLE UDATA
104. igh byte of the 16 bit result L_byte EQU 13 Low byte of the 16 bit result count EQU 14 loop counter mpy CITE H_byte CIr f L byte movlw 8 movwf count movf mulcnd w bcf STATUS C Clear carry bit Loop DEF mulplr F btfsc STATUS C addwf H byte F Erf H byte F ret L_byte F decfsz count F DS33014F page 62 1997 Microchip Technology Inc Chapter 4 goto loop retlw 0 FRR IR e AE K e E E A A e E E e RR RR RR RARA RRA ok ke ek eee Test Program OE EK RRR RR AAR A SDE RON RRR RK EORR E AA start clrw option main movf PORTB w movwt mulplr multiplier in mulplr 05 movf PORTB W movwf mulcnd callm call mpy The result is in F12 amp F13 H byte amp L byte goto main ORG 01FFh goto start END Since a 8x8 bit multiply is a useful generic routine it would be handy to break this off into a separate object file that can be linked in when required The above file can be broken into two files a calling file representing an application and a generic routine that could be incorporated in a library Relocatable Code Calling File LIST P 16C54 INCLUDE P16C5x INC EXTERN mulcnd mulplr H byte L byte EXTERN mpy CODE start clrw option main movf PORTB W movwf mulplr movf PORTB W movwf mulcnd callm call mpy The result is in H byte amp L byte goto main Reset CODE H O1FF goto Start END 1997 Microchip Technology Inc DS33014F page 63 mi gt S M
105. ile There are several reasons for creating library files Libraries make linking easier Since library files can contain many object files the name of a library file can be used instead of the names of many separate object files when linking Libraries help keep code small Since a linker only uses the required object files contained in a library not all object files which are contained in the library necessarily wind up in the linker s output module Libraries make projects more maintainable If a library is included in a project the addition or removal of calls to that library will not require a change to the link process Libraries help to convey the purpose of a group of object modules Since libraries can group together several related object modules the purpose of a library file is usually more understandable than the purpose of its individual object modules For example the purpose of a file named math lib is more apparent than the purpose of power o ceiling o and floor o MPLIB is a librarian for use with COFF object modules created using either MPASM v2 0 MPASMWIN v2 0 or MPLAB C v2 0 or later Usage mplib q ctdrx LIBRARY MEMBER options c create library creates a new LIBRARY with the listed MEMBER s A list members prints a table showing the names of the members in the LIBRARY d delete member deletes MEMBER s from the LIBRARY if no MEMBER is specified the LIBRARY is not altered
106. ith MPLINK and MPLIB P PAGE iria PAGESEL A est tdt E PICMIGIO 13i PICSTART Precedence PRO MATE PROCESSOR PLOCESSOF end processor cocoocconccocccccnnccononnno PROCESSOR directive 115 R RADIX 10 15 18 44 49 71 MEE RAE RAF DON EUR 74 115 RELOCATABLE OBJECTS 57 BEES oer ee et nce 50 S SET iiu 22 30 50 54 110 Shell enea 13 14 16 Software Releases 107 Intermediate Release 107 Production Release 108 Source Code 9 source file SPACE SUBTITLE T Text Strings 72 RnB T 51 U UDATA Latas UDATA_OVR UDATA_SHR V VARIABLE 22 30 54 W Warnings eenee 113 Warranty i caede 10 Web Site connecting to 105 file transfer 105 WHILE 36 55 69 112 WHILE ENDW 112 DS33014F page 154 O 1997 Microchip Technology Inc Index Notes O 1997 Microchip Technology Inc DS33014F page 155 MICROCHIP WORLDWIDE SALES amp SERVICE AMERICAS Corporate Office Microchip Technology Inc 2355 West Chandler Blvd Chandler AZ 85224 6199 Tel 602 786 7200 Fax 602 786 7277 Technical Support 602 786 7627 Web http www microchip com Atlanta Microchip Technology Inc 500 Sugar Mill Road Suite 200B Atlanta GA 30350 Tel 770 640 0034 Fax 770 64
107. ked with other modules Special directives are required in the source code when generating an object file PC Any IBM or compatible Personal Computer PICmicro PICmicro refers to any Microchip microcontroller including the representatives of the PIC12CXXX PIC14XXX PIC16C5X PIC16CXX and PIC17CXX families Source Code This is the ASCII text file of PlCmicro instructions and MPASM directives and macros that will be translated into machine code This code is suitable for use by a PICmicro or Microchip development system product like MPLAB It is an ASCII file that can be created using any ASCII text editor 1997 Microchip Technology Inc DS33014F page 9 MPASM USER S GUIDE with MPLINK and MPLIB Recommended Reading This manual is intended to provide a reference to using the MPASM development environment It is not intended to replace reference material regarding specific PICmicro MCUs Therefore you are urged to read the Data Sheets for the PICmicro MCU specified by your application If this is your first microcontroller application you are encouraged to review the Microchip Embedded Control Handbook You will find a wealth of information about applying PlCmicro MCUs The application notes described within are available from the Microchip BBS and Internet web site see Appendix B All of these documents are available from your local sales office or from your Microchip Field Application Engineer FAE Sys
108. l gt dt lt text_string gt lt text_string gt DW Declare Data of One Wordd lt label gt dw lt expr gt lt expr gt lt expr gt lt label gt dw lt text_string gt lt text_string gt ELSE Begin Alternative Assembly Block to IF else END End Program Block end ENDC End an Automatic Constant Block endc ENDIF End conditional Assembly Block endif ENDM End a Macro Definition endm ENDW End a While Loop endw EQU Define an Assembly Constant label equ lt expr gt ERROR Issue an Error Message error lt text_string gt ERRORLEVEL Set Error Level errorlevel 0 1 2 lt gt lt message number EXITM Exit from a Macro exitm EXPAND Expand Macro Listing expand EXTERN Declares an external label extern lt label gt lt label gt FILL Fill Memory lt label gt fill lt expr gt count GLOBAL Exports a defined label global lt label gt lt label gt DS33014F page 24 O 1997 Microchip Technology Inc Table 3 1 Directive Summary Continued Chapter 3 Directive Description Syntax IDATA Begins initialized data section lt name gt idata lt address gt IDLOCS Specify ID locations idlocs lt expr gt IF Begin ConditionallyAssembled Code if lt expr gt Block IFDEF Execute If Symbol has Been Defined ifdef label IFNDEF Execute If Symbol h
109. lid message number The message number specified for displaying or hiding is not a valid message number Error messages cannot be disabled Error messages cannot be disabled with the ERRORLEVEL command Redefining processor The selected processor is being reselected by the LIST or PROCESSOR directive Use of this instruction is not recommended Use of the TRIS and OPTION instructions is not recommended for a PIC16CXX device Invalid label in operand Operand was not a valid address For example if the user tried to issue a CALL to a MACRO name UNKNOWN WARNING A warning has occurred which MPASM cannot understand It is not any of the warnings described in this appendix Contact your Microchip Field Application Engineer FAE if you cannot debug this warning O 1997 Microchip Technology Inc DS33014F page 115 MPASM USER S GUIDE with MPLINK and MPLIB Messages 301 302 303 304 305 306 307 308 309 310 311 312 MESSAGE User message invoked with the MESSG directive Register in operand not in bank 0 Ensure that bank bits are correct Register address was specified by a value that included the bank bits For example RAM locations in the PIC16CXX are specified with 7 bits in the instruction and one or two bank bits Program word too large Truncated to core size Program words for the PIC16C5X may only be 12 bits program words for the PIC16CXX may only be 14 bits ID Locations v
110. llow the operands mnemonics or labels and can start in any column The maximum column width is 255 characters One or more spaces must separate the label and the mnemonic and the mnemonic and the operand s Multiple operands must be separated by a comma For example DS33014F page 18 O 1997 Microchip Technology Inc Chapter 2 v Example 2 2 Sample MPASM Source Code eu mb Sample MPASM Source Code For illustration only list p 16c54 y Dest equ H OB o org H O1FF goto Start org H 0000 Start moviw H OA movwf Dest goto Start end Labels A label must start in column 1 It may be followed by a colon space tab or the end of line Labels must begin with an alpha character or an under bar and may contain alpha numeric characters the under bar and the question mark Labels may be up to 32 characters long By default they are case sensitive but case sensitivity may be overridden by a command line option If a colon is used when defining a label it is treated as a label operator and not part of the label itself Mnemonics Assembler instruction mnemonics assembler directives and macro calls must begin in column 2 or greater If there is a label on the same line instructions must be separated from that label by a colon or by one or more spaces or tabs Operands Operands must be separated from mnemonics by one or more spaces or tabs Multiple ope
111. locatable Code CODE Start CLRW OPTION O 1997 Microchip Technology Inc DS33014F page 57 MPASM USER S GUIDE with MPLINK and MPLIB If more than one CODE section is defined in a source file each section must have a unique name If the name is not specified it will be given the default name code Each program memory section must be contiguous within a single source file A section may not be broken into pieces within a singe source file The physical address of the code can be fixed by supplying the optional address parameter of the CODE directive Situations where this might be necessary are Specifying interrupt vectors Ensuring that a code segment does not overlap page boundaries Example Relocatable Code Reset CODE H OlFF GOTO Start Main CODE CLRW OPTION Instruction Operands There are some restrictions involving instruction operands Instruction operands must be of the form HIGH LOW relocatable symbol constant offset where e relocatable symbol is any label that defines a program or data memory address constant offset is an expression that is resolvable at assembly time to a value between 32768 and 32767 Either lt relocatable symbol or lt constant offset may be omitted Operands of the form relocatable symbol relocatable symbol will be reduced to a constant value if both symbols are defined in the same code or data section RAM Allocation RAM spac
112. m pub microchip The web site and file transfer site provide a variety of services Users may download files for the latest Development Tools Datasheets Application Notes User s Guides Articles and Sample Programs A variety of Microchip specific business information is also available including listings of Microchip sales offices distributors and factory representatives Other data available for consideration is Latest Microchip Press Releases Technical Support Section with Frequently Asked Questions Design Tips Device Errata Job Postings Microchip Consultant Program Member Listing Links to other useful web sites related to Microchip Products O 1997 Microchip Technology Inc DS33014F page 105 MPASM USER S GUIDE with MPLINK and MPLIB Connecting to the Microchip BBS Connect worldwide to the Microchip BBS using either the Internet or the CompuServe communications network Internet You can telnet or ftp to the Microchip BBS at the address mchipbbs microchip com CompuServe Communications Network In most cases a local call is your only expense The Microchip BBS connection does not use CompuServe membership services therefore You do not need CompuServe membership to join Microchip s BBS There is no charge for connecting to the BBS except for a toll charge to the CompuServe access number where applicable You do not need to be a CompuServe member to take advantage of this connection you
113. ment f 1 gt f and d 14ff INCF d Increment f 1 gt f and d b3kk IORLW k Inclusive OR literal with W W OR k gt W 08ff IORWF f d Inclusive or W with f W OR f d bOkk MOVLW k Move literal to W k oW bckk MULLW k Multiply literal and W k x W gt PH PL 34ff MULWF Multiply W and f W x f PH PL 2cff NEGW da Negate W store in f and d W 1 gt W 1 gt d laff RLCF d Rotate left through carry register C el A 0 pb 22ff RLNCF f d Rotate left no carry register f er ne 0 lt a 18 f RRCF d Rotate right through carry register lud C Pa PT TERT Ged 0 20ff RRNCF d Rotate right no carry register KEEN 0 2aff SETF d Setf and Set d Oxff gt f 0xff gt d b2kk SUBLW k Subtract W from literal k W gt W 04ff SUBWF f d Subtract W from f W d O2ff SUBWFB d Subtract from f with borrow W c d lcff SWAPF f d Swapf 0 3 gt d 4 7 4 7 gt d 0 3 b4kk XORLW k Exclusive OR literal with W W XOR k gt W Ocff XORWF d Exclusive OR W with f W XOR f gt d 1997 Microchip Technology Inc DS33014F page 137 MPASM USER S GUIDE with MPLINK and MPLIB Table E 14 PIC17CXX Bit Handling Instructions Hex Mnemonic Description Function 8bff BCF f b Bit clear f 0 gt f b 8bff BSF f b Bit set f 1 gt f b
114. mp3 RES 1 If necessary the location of the section may be fixed in memory by supplying the optional address parameter lf more than one of each section type is specified each section must have a unique name If a name is not provided the default section names are idata udata and udata ovr When defining initialized data in an IDATA section the directives DB DW and DATA can be used DB will define successive bytes of data memory DW and DATA will define successive words of data memory in low byte high byte order The following example shows how data will be initialized 1997 Microchip Technology Inc DS33014F page 59 MPASM USER S GUIDE with MPLINK and MPLIB Relocatable Code 00001 LIST p 17C44 00002 IDATA 0000 01 02 03 00003 Bytes D8 Enr 0003 34 12 78 56 00004 Words DW H 1234 H 5678 0007 48 69 00 00005 String DB Ha 0 Configuration Bits and ID Locations Configuration bits and ID locations can still be defined in a relocatable object using the coNFIGand _ IDLOCS directives Only one linked module can specify these directives They should be used prior to declaring any CODE sections After using these directives the current section is undefined Accessing Labels From Other Modules Labels that are defined in one module for use in other modules must be exported using the GLOBAL directive Labels must be defined before they are declared GLOBAL Modules that use these labels must use the EXTERN directi
115. n mnemonics that are not the same between the machines assuming that register and peripheral usage were similar The rest of the directive and macro language will be the same O 1997 Microchip Technology Inc DS33014F page 3 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 4 1997 Microchip Technology Inc MICROCHIP Product Definition Using MPASM MPASM USER S GUIDE with MPLINK and MPLIB Chapter 1 Introduction MPASM is a DOS or Windows based PC application that provides a platform for developing assembly language code for Microchip s 12 14 and 16 bit microcontroller families Generically MPASM will refer to the entire development platform including the macro assembler and utility functions MPASM can be used in two ways To generate absolute code that can be executed directly by a microcontroller To generate object code that can be linked with other separately assembled or compiled modules Absolute code is the default output from MPASM When a source file is assembled in this manner all values used in the source file must be defined within that source file or in files that have been explicitly included If assembly proceeds without errors a HEX file will be generated containing the executable machine code for the target device This file can then be used in conjunction with a device programmer to program the microcontroller This process is shown below ES
116. n or variable defined outside the current module A process performed by the linker in which external symbol defintions from all input modules are collected in an attempt to update all external symbol references Any external symbol references which do not get updated cause a linker error to be reported An ASCII file containing hexadecimal addresses and values suitable for programming a device Data which is defined with an initial value In C int myVar 5 defines a variable which will reside in an initialized data section A function or variable has internal linkage if it can not be accessed from outside the module in which it is defined 1997 Microchip Technology Inc DS33014F page 95 MPASM USER S GUIDE with MPLINK and MPLIB Object File A module which may contain relocatable code or data and references to external code or data Typically multiple object modules are linked to form a single executable output Raw Data The binary representation of code or data associated with a section Relocatable Section A section whose address in not fixed The linker assigns addresses to relocatable sections through a process called relocation Relocation A process performed by the linker in which absolute addresses are assigned to relocatable sections and all identifier symbol definitions within the relocatable sections are updated to their new addresses Section An aggregate of code or data which has a name
117. ndented two spaces displays the 32 bit value of any symbols created with the SET EQU VARIABLE CONSTANT or CBLOCK directives The third column also four characters wide is reserved for the machine instruction This is the code that will be executed by the PICmicro MCU The fourth column lists the associated source file line number for this line The remainder of the line is reserved for the source code line that generated the machine code Errors warnings and messages are embedded between the source lines and pertain to the following source line The symbol table lists all symbols defined in the program The memory usage map gives a graphical representation of memory usage X marks a used location and marks memory that is not used by this object The memory map is not printed if an object file is generated Error File Format ERR MPASM by default generates an error file This file can be useful when debugging your code The MPLAB Source Level Debugger will automatically open this file in the case of an error The format of the messages in the error file is type number file line description For example Error 113 C PROG ASM 7 Symbol not previously defined start Appendix C describes the error messages generated by MPASM imc RR RR E RR HUBIESE n n DS33014F page 22 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 3
118. never actually log in to CompuServe The procedure to connect will vary slightly from country to country Please check with your local CompuServe agent for details if you have a problem CompuServe service allow multiple users at baud rates up to 14400 bps The following connect procedure applies in most locations 1 Set your modem to 8 bit No parity and One stop 8N1 This is not the normal CompuServe setting which is 7E1 Dial your local CompuServe access number Depress Enter and a garbage string will appear because CompuServe is expecting a 7E1 setting Type depress lt Entert gt and Host Name will appear Type MCHIPBBS depress lt Enter gt and you will be connected to the Microchip BBS In the United States to find the CompuServe phone number closest to you set your modem to 7E1 and dial 800 848 4480 for 300 2400 baud or 800 331 7166 for 9600 14400 baud connection After the system responds with Host Name type NETWORK depress Enter and follow CompuServe s directions For voice information or calling from overseas you may call 614 723 1550 for your local CompuServe number Using the Bulletin Board The bulletin board is a multifaceted tool It can provide you with information on a number of different topics Special Interest Groups Files Mail Bug Lists DS33014F page 106 1997 Microchip Technology Inc Appendix B On Line Support Special Interest Groups Special
119. ng Page Eject 0 eee eee 48 PAGESEL Generate Page Selecting Code 2 eee 48 PROCESSOR Set Processor Type 0 0 eee eee eee eee 49 RADIX Specify Default Radix 0 0 0 cece ee 49 RES Reserve Memory 00 e eee ete 50 SET Define an Assembler Variable 00 00 c eee eee 50 SPACE Insert Blank Listing Lines llle 51 SUBTITLE Specify Program Subtitle oooocooooocooo 51 TITLE Specify Program Title o oooooocoooooooroooooooooo 51 UDATA Begin an Object File Uninitialized Data Section 52 UDATA OVR Begin an Object File Overlayed Uninitialized Data Section 52 UDATA SHR Begin an Object File Shared Uninitialized Data Section 53 UNDEFINE Delete a Substitution Label o oooooooooo o 54 VARIABLE Declare Symbol Variable llle 54 WHILE Perform Loop While Condition is True ooo oooooo 55 Using MPASM to Create Relocatable Objects Introduction Li elc uem eme oU d Ree RE acacia TES EXAM 57 Highlights ix er pP RYDER QI Se EP 57 Header Files kie er e got te Pate ROT OR RUE UR E Russ 57 Program Memory xut ttg ED AR LR RC 57 Instruction Operands o oocoococco Ie 58 RAM Allocation i erue Rom Tum Lee Ve uie i e Re 58 Configuration Bits and ID Locations o oococcccorocco nooo 60 Accessing Labels From Other Modules 00000 eee eee 60 Paging and Ba
120. nking ISSUES o coooocccccr ene 61 Unavailable Directives o oooooocororororr eens 62 Generating the Object Module 0000 eee eee eee 62 Example iii rra aia Eid 62 Macro Language Introd ction i xr dan EE we dee eens Bias A eee Xe FL Reda 65 Highlights ERA PRRREDEIRDR E MERI Mg rue e teh 65 1997 Microchip Technology Inc DS33014F page v MPASM USER S GUIDE with MPLINK and MPLIB Chapter 6 Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 T S ce A A A ee te eee ici 65 MACONDO ee a eg 66 Macro Directives nip paina omo in fa eter ue TOS wheel aed 66 Text Substitution ez te Mee Pee A uetus Ble 67 Macro Usage ene be neri edi aia deed doe taeda den E 67 Examples iia ai atte ele Rta wide A hee a ier 68 Expression Syntax and Operation Introduction reinos hacked rd de ede Ox bed dee prr 71 Highlights m ot ROA eae Rae a She eae Be eae et LEFT 71 Tel ms it A et e EL ADIRE sat 71 Text Strings uu ia o reed ae x re e Eb EIS V ee 72 Numeric Constants and Radix ooococcoccoo eee 74 High EOW x voit e heb a EX PIN Fa pa ER ERG EAE 76 Increment Decrement l l ne 76 Part 2 MPLINK Introduction MPLINK Preview ner ebbe e D RR EVI EDS EE m e 79 Product Description ue erg Rx mr EEG URDU ve AIRE 79 File Formats e socer Do viet RUE URINE VE FH PR eu ue 80 Linker Components socre nri r 0 00 c eI eee 80 Tools and Supported Platforms 0 0 c eee 81
121. nt out of range Least significant bits used Argument did not fit in the allocated space For example literals must be 8 bits O 1997 Microchip Technology Inc DS33014F page 113 MPASM USER S GUIDE with MPLINK and MPLIB 203 204 205 206 207 208 209 210 211 212 213 214 215 Found opcode in column 1 An opcode was found in column one which is reserved for labels Found pseudo op in column 1 A pseudo op was found in column one which is reserved for labels Found directive in column 1 A directive was found in column one which is reserved for labels Found call to macro in column 1 A macro call was found in column one which is reserved for labels Found label after column 1 A label was found after column one which is often due to a misspelled opcode Label truncated at 32 characters Maximum label length is 32 characters Missing quote A text string or character was missing a quote For example DATA a Extra An extra comma was found at the end of the line Extraneous arguments on the line Extra arguments were found on the line These warnings should be investigated since they are often indications of the free format parser interpreting something in a manner other than was intended try assembling OPTION EQU 0x81 with LIST FREE Expected Expected a certain type of argument A description should be provided For the warning an assumption is made a
122. ntrol Instructions Hex Mnemonic Description Function 0004 CLRWT Clear watchdog timer 0 gt WDT 0 WDT prescaler 19 PD 1 gt TO 0003 SLEEP Enter Sleep Mode Stop oscillator power down 0 gt WDT 0 WDT Prescaler 1 PD 1 gt TO Hexadecimal to Decimal Conversion 0 0 0 0 0 0 0 0 A 2 3 4 5 6 7 8 9 0 1 A um N as 99 A A TN mM OO O gt o0o Oo0o NI oa a AJOJN nim O O O gt 0O Oo0o NI aJ a AJOJN TNM M OO O gt 0o Oo0o NI oO oa AJOJN zx al Using This Table For each Hex digit find the associated decimal value Add the numbers together For example Hex A38F converts to 41871 as follows Hex 1000 s Digit Hex 100 s Digit Hex 10 s Digit Hex 1 s Digit Result 40960 768 128 15 41871 Decimal O 1997 Microchip Technology Inc DS33014F page 139 MPASM USER S GUIDE with MPLINK and MPLIB ASCII Character Set Most Significant Character 0 1 4 5 6 0 NUL DLE Space 0 O P p 1 SOH DC1 1 A Qa q 2 STX DC2 2 B R b r 5 3 ETX DC3 3 Gell zS c s 8 4 EOT DC4 4 D T d t 5 5 eno ma 0 5 E ule Jou S 6 ACK SYN amp 6 F v f v 7 Bell ETB 7Z G wlglw B 8 BS CAN 8 Hx h x 3 9 HT EM 9 Y i y A LF SUB J Z j z B VT ESC K k
123. o true the code immediately following the IF will assemble Otherwise subsequent code is skipped until an ELSE directive or an ENDIF directive is encountered An expression that evaluates to zero is considered logically FALSE An expression that evaluates to any other value is considered logically TRUE The IF and WHILE directives operate on the logical value of an expression A relational TRUE expression is guaranteed to return a non zero value FALSE a value of zero Example if version 100 check current version moviw 0x0a movwf io 1 else moviw 0x01a 1997 Microchip Technology Inc DS33014F page 41 MPASM USER S GUIDE with MPLINK and MPLIB movwf io 2 endif See Also ELSE ENDIF IFDEF Execute If Symbol has Been Defined Syntax ifdef label Description If lt labe1 gt has been previously defined usually by issuing a DEFINE directive or by setting the value on the MPASM command line the conditional path is taken Assembly will continue until a matching ELSE or ENDIF directive is encountered Example define testingl set testing on ifdef testing lt execute test code gt this path would endif be executed See Also DEFINE ELSE ENDIF IFNDEF UNDEFINE IFNDEF Execute If Symbol has not Been Defined Syntax ifndef lt label gt Description If lt label gt has not been previously defined or has been undefined by issuing an UNDEFINE directive then the code following
124. ology Inc MICROCHIP MPASM USER S GUIDE with MPLINK and MPLIB Appendix E Quick Reference The following Quick Reference Guide gives all the instructions directives and command line options for the Microchip MPASM Assembler Table E 1 MPASM Directive Language Summary Directive Description Syntax CONTROL DIRECTIVES CONSTANT Declare Symbol Constant constant lt label gt lt expr gt lt label gt lt expr gt DEFINE Define a Text Substitution Label define lt name gt lt arg gt lt arg gt lt value gt END End Program Block end EQU Define an Assembly Constant lt label gt equ lt expr gt ERROR Issue an Error Message error lt text_string gt ERRORLEVEL Set Messge Level errorlevel 0 1 2 lt gt lt msg gt INCLUDE Include Additional Source File include lt lt include_file gt gt include lt include_file gt LIST Listing Options list lt option gt lt option gt MESSG Create User Defined Message messg lt message_text gt NOLIST Turn off Listing Output nolist ORG Set Program Origin lt label gt org lt expr gt PAGE Insert Listing Page Eject page PROCESSOR Set Processor Type processor lt processsor_type gt RADIX Specify Default Radix radix lt default_radix gt 1997 Microchip Technology Inc DS33014F page 125 MPASM USER S GUIDE with MPLINK and MPLIB
125. on code using an algorithm that uses right shifts and adds for each bit set in the eight bits of the multiplier The WHILE directive is used for this function continuing the loop until i is greater than or equal to eight The end of the loop is noted by the ENDw directive Execution continues with the statement immediately following the ENDw when the WHILE condition becomes TRUE The entire macro is terminated by the ENDM directive Constant Compare As another example if the following macro were written include l6cxx reg compare file to constant and jump if file gt constant cfl jge macro file con jump to movlw con amp Oxff subwf file w btfsc status carry goto jump to endm and invoked by cfl jgeswitch val max switch switch on it would produce movlw max switch amp Oxff subwf switch val w btfsc status carry goto Switch on O 1997 Microchip Technology Inc DS33014F page 69 mi gt S MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 70 O 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 6 Expression Syntax and Operation Introduction This chapter describes various expression formats syntax and operations used by MPASM Highlights The points that will be highlighted in this chapter are Text Strings Numeric Constants and Radix Arithmetic Operators and Precedence Hi
126. on values of the data are stored BANKSEL init entry from addr movfp init entry from addr WREG movwf TBLPTRL movfp init entry from addr 1 WREG movwf TBLPTRH We must determine whether the data section is in the general purpose area of RAM or in the special function register SFR area We do this by comparing the address with the register memory map We then determine whether to alter the upper or lower nibble of the BSR register in preparation for copying the data BANKSEL init entry to addr movfp init entry to addr FSRO First we see if destination is GPR gt 0x20 movlw 0x1f cpfslt init entry to addr n If it is 0x1F continue testing goto init sec gpr otherwise it s 0x20 or higher GPR It s not GPR let s see if it s SFR or unbanked between 0x18 and 0x1F movlw 0x18 cp slt init entry to addr jis it 17 goto Start copying data No it s between 0x18 and 0x1F It s lt 17 let s see if it is 0x00 0x0F or 0x10 0x17 movlw Ox0F cpfsgt init_entry_to_addr goto _start_copying_data It s between 0x00 and 0x0F COPY DS33014F page 150 1997 Microchip Technology Inc Appendix F Example Initialization Code if we fall through it s an SFR from 0x10 0x17 OK it s an SFR that needs MOVLB type of bank switching First mask off low nibble of BSR moviw OxFO andwf BSR 1 Clear the low nibble movfp init_entry_to_addr 1 WREG Load high portion of address iorwf BSR 1 and paste
127. opy_idata_sec CODE KKK KKK KKK KKK KKK KK KK KKK KKK KKK KKK KK KKK KKK KKK KKK KK KKK KKK KKK KKK KKKKK Copy initialized data from ROM to RAM KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KK KKK KK KKK KKK KK KKKK DS33014F page 142 1997 Microchip Technology Inc Appendix F Example Initialization Code The values program memo Stored in da PASM or Such section in Section Eac where the da memory where H The startu addresses an _cinit to be stored in initialized data are stored in ry sections The actual initialized variables are ta memory in a section defined by the IDATA directive automatically defined by MPLAB C The table below has an entry for each There are num init S in a program h entry contains the starting address in program memory ta is to be copied from the starting address in data the data is to be copied and the number of bytes to copy p code below walks the table d counts reading those starting and copies the data from program to data memory try from addr low high try_from_addr try_to_addr low high try_to_addr init_en init_en init_en it_en init_en init_en low high try_from_addr try_from_addr low high try_to_addr try_to_addr 1997 Microchip Technology Inc IDATA IDATA 0 num_init DS33014F page
128. oving the PROTECTED attribute or the number of input sections must be reduced Section secName has a memory memName which can not fit the absolute section Section secName start 0xHHHH length 0xHHHH The memory which was assigned to the section in the linker command file either does not have space to fit the section or the section will overlap another section Use the m lt mapfile gt switch to generate an error map file The error map will show the sections which were allocated prior to the error Section secName can not fit the absolute section Section secName start 0xHHHH length 0xHHHH A section which has not been assigned to a memory in the linker command file can not be allocated Use the m lt mapfile gt switch to generate an error map file The error map will show the sections which were allocated prior to the error More memory must be made available by adding a CODEPAGE SHAREBANK or DATABANK directive or by removing the PROTECTED attribute or the number of input sections must be reduced Symbol symName has multiple definitions A symbol may only be defined in a single input module Could not resolve symbol symName in file File The symbol symName is an external reference No input module defines this symbol If the symbol is defined in a library module ensure that the library module is included on the command line or in the linker command file using the FILES directive Could not open map
129. patch their corresponding sections The final assembly equivalent output for the above example would be 0x0050 MOVLW OxFF 0x0051 MOVLR 0x1 Patched with varl s bank 0x0052 MOVWF 0x25 Patched with varl s offset Initialized Data MPLINK performs special processing for input sections with initialized data Initialized data sections contain initial values initializers for the variables and constants defined within them Because the variables and constants within an initialized data section reside in RAM their data must be stored in non volatile program memory ROM For each initialized data section the linker creates a section in program memory The data is moved by initializing code supplied with MPLAB C and MPASM to the proper RAM location s at startup 1997 Microchip Technology Inc DS33014F page 93 MPASM USER S GUIDE with MPLINK and MPLIB The names of the initializer sections created by the linker are the same as the initialized data sections with a i appended For example if an input object module contains an initialized data section named idata main o the linker Will create a section in program memory with the name idata main o i which contains the data In addition to creating initializer sections the linker creates a section named cinit in program memory The cinit section contains a table with entries for each initialized data section Each entry is a triple which specifies where in pro
130. ple test macro filereg Xf filereg check for valid file exitm else error bad file assignment O 1997 Microchip Technology Inc DS33014F page 37 MPASM USER S GUIDE with MPLINK and MPLIB endif endm See Also MACRO ENDM EXPAND Expand Macro Listing Syntax expand Description Expand all macros in the listing file This directive is roughly equivalent to the m MPASM command line option but may be limited in scope by the occurrence of a subsequent NOEXPAND See Also MACRO NOEXPAND EXTERN Declare an Externally Defined Label Syntax extern label lt label gt Description For use when generating an object file Declares symbol names that may be used in the current module but are defined as global in a different module The EXTERN statement must be included before the 1abe1 is used At least one label must be specified on the line No lt 1abe1 gt can be defined in the current module For more information refer to Chapter 4 Using MPASM to Create Relocatable Objects Example extern Function call Function See Also TEXT IDATA UDATA UDATA OVR UDATA SHR GLOBAL DS33014F page 38 O 1997 Microchip Technology Inc Chapter 3 y Q FILL Specify Memory Fill Value um Syntax lt labe1 gt fill lt expr gt lt count gt gt Description o Generates count occurrences of the program word lt expr gt If bounded by parentheses lt expr gt can be an
131. previously declared using a DATABANK or SHAREBANK statement Example To set the stack size to be 0x20 the following line should be added to the linker command file STACK SIZE 0x20 RAM gpr0 Linker Command File Example The following is an example linker command file for the PIC17C 44 INCLUDE user lkr Include another linker command file LIBPATH c projects current Add a directory to the search path CODEPAGE NAME vectors CODEPAGE NAME page0 DATABAN AME sfr0 DATABAN AME sfrl DATABAN AME sfr2 DATABAN AME sfr3 DATABANK NAME gpr0 DATABANK NAME gpr1 SHAREBANK NAME sfrShare START 0x0EN SHAREBANK SHAREBANK NAME sfrShare START 0x200 SHAREBANK NAME sfrShare START 0x300 SECTION AME cinit SECTION AME code SECTION AME udata START 0x0END 0x20 ROM area for reset int vectors START 0x21END 0x1FFF User program memory area START 0x10END 0x17 Special function reg s in RAM bank 0 START 0x110END 0x117 Special function reg s in RAM bank 1 START 0x210END 0x217 Special function reg s in RAM bank 2 START 0x310END 0x317 Special function reg s in RAM bank 3 START 0x20END 0xFF General purpose RAM bank 0 START 0x120END 0x1FF General purpose RAM bank 1 0xF Shared unbanked SFR s ND 0x20F Shared unbanked SFR s ND 0x30F Shared unbanked SFR s D AME sfrShare START 0x100END 0x10F Shared unbanked SFR s ROM page0 cinit section resides in ROM ROM page0 code section reside
132. pter 2 Chapter 3 Part 1 MPASM Welcome aient o a are cd eb iade oci des dec RI Elo ta 3 Feature List and Product Information oooooccooocorocro eee 3 Migration Path cnr rii mere rar a G RI equ ie ILhemnier 3 Introduction Product Definition ss ceecee ep ee E a E A E E a EA E 5 Using MPASM tc a A a aara E a UE e da 5 Documentation Layout esniak i aE aa eee 7 TEMS serrie ea a eer eg Pn E PIDE ae a eee VERD E See 8 Recommended Reading 0 cee eee een 10 System Requirements 0 0 eee eee eee 10 Warranty Registration 0 0 llle III 10 Installation ici tedio PIA Uus es A ES 10 Compatibility ISSUOS wn eve eee ee A ERR EE 10 Customer Support nis cue re RI RD PEG wk EY X e mul E Rum 11 Environment and Usage INTOCUCION cris ae ac Rae TESCO Dea Eg Ld Ere 13 Highlights 3 cde E REESE ERREUR ERROR 13 Tetris Sect eu NUS Wir cao ite Eu RU IQ EE eue 13 Command Line Interface ooooococccccocooo eee 14 DOS Shell Interface misions aer n a e a d le 16 Windows Shell Interface nunan nanana 17 Source Code Formats serico reipi e i a eee eee 18 Files Used by MPASM and Utility Functi0NS 0o ooooooo o 20 Hex File Formats aint a ra e a a TR I 20 Listing File Formalt REO RE A a 21 Error File Format GERR ic ies I te dota baleen beeps LR Tech RR 22 Directive Language Introd ictiori cote ELE LIA RUE d ea NEEPUPD B AUN E 23 Highlights ee i A EN No Rois dos t 23 O 1
133. ptions Option Default Description N A Displays the MPASM Help Panel a INHX8M Set hex file format a lt hex format gt where hex format is one of INHX8M INHX8S INHX32 c On Enable Disable case sensitivity d None Define symbol dDebug dMax 5 dString abc e On Enable Disable Set Path for error file h N A Displays the MPASM Help Panel On Enable Disable Set Path for the listing file m On Enable Disable macro expansion o Off Enable Disable Set Path for the object file DS33014F page 14 O 1997 Microchip Technology Inc Chapter 2 UU Table 2 1 Assembler Command Line Options Continued ms E p None Set the processor type l p lt processor_type gt where lt processor_type gt is a PICmicro device for example PIC16C54 y q Off Enable Disable quiet mode suppress screen output dp r Hex Defines default radix r lt radix gt where lt radix gt isone of HEX DEC OCT t 8 List file tab size t lt size gt w 0 Set message level w lt level gt where 1evel is one of 01112 0 all messages 1 errors and warnings 2 errors only x Off Enable Disable Set Path for cross reference file 1997 Microchip Technology Inc DS33014F page 15 MPASM USER S GUIDE with MPLINK and MPLIB DOS Shell Interface The MPASM DOS Shell interface displays a screen in Text Graphics mode On
134. py data for each entry Decrement num init every time initialization and when it reaches 0 we are done copying initialization data loop num init BANKSEL num init movf num init W iorwf num init 1 0 btfss STATUS Z goto Copy init sec n goto end copy init data n For a single initialization section Starting addresses in both program and as well as the number of bytes to copy copy init sec Read from address in program memory BANKSEL init entry from addr If num init is not down to 0 then we have more sections to copy otherwise we re done copying data read the data memory tablrd 0 1 init entry from addr tlrd 0 init entry from addr tipa 1 init_entry_from_addr 1 Read to address in data memory BANKSEL init entry to addr tablrd 0 1 init entry to addr tlrd 0 init entry to addr tlrd 1 init entry to addr 1 Read size of data to be copied in BYTES BANKSEL init entry size tablrd 0 1 init entry size O 1997 Microchip Technology Inc DS33014F page 149 MPASM USER S GUIDE with MPLINK and MPLIB tlrd 0 init entry size tlrd 1 init entry size 1 We must save the position of TBLPTR since TBLPTR is used in copying the data as well movfp TBLPTRL WREG BANKSEL save tblptrl movwf save tblptrl movfp TBLPTRH WREG BANKSEL save tblptrh movwf save tblptrh Setup TBLPTRH TBLPTRL to point to the ROM section where the initializati
135. r all relocatable assigned sections have been allocated the linker allocates relocatable unassigned sections The linker starts with the largest relocatable unassigned section and works its way down to the smallest relocatable unassigned section For each allocation it chooses the target memory block with the smallest available space that can accomodate the section By starting with the largest section and choosing the smallest accomodating space the linker increases the chances of being able to allocate all the relocatable unassigned sections The stack is not a section but gets allocated along with the sections The linker command file may or may not assign the stack to a specific target memory block If the stack is assigned a target memory block it gets allocated just before the relocatable assigned sections are allocated If the stack is unassigned then it gets allocated after the relocatable assigned sections and before the other relocatable unassigned sections are allocated Relocation Example The following example illustrates how the linker relocates sections Suppose the following source code fragment occurred in a file File ref c char varl Line 1 void setVarl void Line 2 varl OxFF Line 3 DS33014F page 92 O 1997 Microchip Technology Inc Chapter 5 Linker Processing Suppose this compiles into the following assembly instructions note this example deliberately ignores any code gen
136. rands must be separated by commas Comments MPASM treats anything after a semicolon as a comment All characters following the semicolon are ignored String constants containing a semicolon are allowed and are not confused with comments 1997 Microchip Technology Inc DS33014F page 19 MPASM USER S GUIDE with MPLINK and MPLIB Files Used by MPASM and Utility Functions These are the default file extensions used by MPASM and the associated utility functions Table 2 3 MPAM Default Extensions Extension Purpose ASM Default source file extension input to MPASM source name ASM LST Default output extension for listing files generated from MPASM lt source_name gt LST ERR Output extension from MPASM for specific error files lt source_name gt ERR HEX Output extension from MPAS for hex files see Appendix A source name HEX HXL HXH Output extensions from MPASM for separate low byte and high byte hex files source name HXL source name HXH COD Output extension for the symbol and debug file This file may be output from MPASM or MPLINK source name COD O Output extension from MPASM for object files lt source_name gt O Hex File Formats MPASM is capable of producing different hex file formats See Appendix A Hex File Formats DS33014F page 20 O 1997 Microchip Technology Inc Listing File Format Chapter 2
137. rgument text supplied as part of the macro invocation v lt expr gt Return the integer value of lt expr gt Typically used to create unique variable names with common prefixes or suffixes Cannot be used in conditional assembly directives e g IFDEF WHILE Arguments may be used anywhere within the body of the macro except as part of normal expression For example the following macro define_table macro local a 0 while a 3 entry v a dw 0 a 1 endw endm would generate entry0 dwO entryl dwO entry2 dwO entry3 dw0 when invoked Macro Usage Once the macro has been defined it can be invoked at any point within the source module by using a macro call as described below macro name arg lt arg gt where macro name is the name of a previously defined macro and arguments are supplied as required O 1997 Microchip Technology Inc DS33014F page 67 MPASM USER S GUIDE with MPLINK and MPLIB The macro call itself will not occupy any locations in memory However the macro expansion will begin at the current memory location Commas may be used to reserve an argument position In this case the argument will be an empty string The argument list is terminated by white space or a semicolon The EXITM directive see Chapter 3 provides an alternate method for terminating a macro expansion During a macro expansion this directive causes expansion of the current macro to stop
138. rrors and warnings 2 errors Off enable disable set path for cross reference file Ix Enable Ix Enable Ix Disable x lt path gt xref file Enables sets path DS33014F page 128 1997 Microchip Technology Inc Appendix E Quick Reference Table E 3 Radix Types Supported Radix Syntax Example Decimal D digits D 100 Hexadecimal default H hex digits H 9f Octal O octal digits OCT Binary B binary digits B 00111001 Character character tt A lt Character gt A C O 1997 Microchip Technology Inc DS33014F page 129 MPASM USER S GUIDE with MPLINK and MPLIB Table E 4 MPASM Arithmetic Operators Operator Description Example Current program counter goto 3 Left Parenthesis 1 d 4 Right Parenthesis Length 1 256 Item NOT logical complement if a b Complement flags flags Negation 2 s complement 1 Length high Return high byte movlw high CTR Table low Return low byte movlw low CTR Table i Multiply a b c Divide a b c 96 Modulus entry len tot len 16 Add tot len entry len 8 1 Subtract entry len tot 1 8 Left shift val flags lt lt 1 gt gt Right shift val flags gt gt 1 gt Greater or equal if entry_idx gt num_entries gt Great
139. ry size t1 1 O 1997 Microchip Technology Inc DS33014F page 145 MPASM USER S GUIDE with MPLINK and MPLIB decf init entry size 1 goto start copying data Back to do another section dec num init BANKSEL num init movf num init 1 btfsc STATUS Z decf num init 1 1 decf num init 1 goto loop num init end copy init data We re done copying initialized data return Must declare copy init data as GLOBAL to be able to call it from other assembly modules GLOBAL copy init data END DS33014F page 146 1997 Microchip Technology Inc Appendix F Example Initialization Code Initialization Code for the PIC17CXX KKK KK KKK KKK KK KKK KKK KK KK KKK KKK KKK KKK KK KKK KKK KKK KKK KKK KKK KKK ckckckck kockckckckck a mer PIC17Cxx MPASM Initialized Data Startup File Version 0 01 kes ee c Copyright 1997 Microchip Technology PX KKK KKK KKK KKK KKK KKK KKK KK KK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KKK KK KKK Plat rcr E EQquates Soe SS Se es i Register addresses INDF equ 0x00 PCL equ 0x02 STATUS equ 0x03 FSR equ 0x04 PCLATH equ 0x0A Bits within registers Z equ 0x02 C equ 0x00 Fiat a ia E External variables and labels i EXTERN _cinit Start of const data table j F FEK IR E AE K E E E A He e E E E AE RIA AIA IAI IRA A k AA EG KI GG VARIABLES UDATA OVR Data used for copying const data into RAM NOTE ALL THE LOCATIONS IN THIS SECTION CAN BE REUS
140. s in ROM RAM gpr0 Unitialized data occupies RAM STACK SIZE 0x20 RAM gpr0 Specify stack size and location DS33014F page 88 1997 Microchip Technology Inc n MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 4 Linker Map File Linker Map File As an option a map file can be generated by the linker The map file contains three tables The first table displays information about each section The information includes the name of the section its type beginning address whether the section resides in program or data memory and its size in bytes There are four types of sections code initialized data idata ninitialized data udata initialized rom data romdata U The following table is an example of the the section table in a map file D Section Info N Section Type Address Location Size Bytes Reset code 0x0000 program 0x0002 cinit romdata 0x0021 program 0x0004 U code code 0x0023 program 0x0026 m udata udata 0x0020 data 0x0005 d The second table in the map file provides information about the symbols in the output module The table is sorted by the symbol name and includes the address of the symbol whether the symbol resides in program or data memory whether the symbol has external or static linkage and the name of the file where defined The following table is an example of the symbol table sorted by symbol name in a map file Symbols Sorted by Name Name Address
141. s the minor number and zz is the intermediate number Intermediate Release Intermediate released software represents changes to a released software system and is designated as such by adding an intermediate number to the version number Intermediate changes are represented by e Bug Fixes Special Releases Feature Experiments Hom a m a Ee 1997 Microchip Technology Inc DS33014F page 107 MPASM USER S GUIDE with MPLINK and MPLIB Intermediate released software does not represent our most tested and stable software Typically it will not have been subject to a thorough and rigorous test suite unlike production released versions Therefore users should use these versions with care and only in cases where the features provided by an intermediate release are required Intermediate releases are primarily available through the BBS Production Release Production released software is software shipped with tool products Example products are PRO MATE ll PICSTART and PICMASTER The Major number is advanced when significant feature enhancements are made to the product The minor version number is advanced for maintenance fixes and minor enhancements Production released software represents Microchip s most stable and thoroughly tested software There will always be a period of time when the Production Released software is not reflected by products being shipped until stocks are rotated You should always check the BBS or the
142. s the word in data memory R low byte first The macro also handles all paging and or bank switching involved Arguments O 1997 Microchip Technology Inc DS33014F page 141 MPASM USER S GUIDE with MPLINK and MPLIB RomAddr Source address in program memory A RamAddr Destination address in data memory H COPY ROM WORD TO RAM MACRO RomAddr RamAddr PAGESEL RomAddr n Switch to correct ROM page call RomAddr then read the low byte BANKSEL RamAddr A Switch to correct RAM bank movwf RamAddr then write the low byte call 1 RomAddr i Read the high byte from ROM movwf 1 RamAddr and store it in RA ENDM KKK KKK KKK KKK KKK KKK KK KK KKK KKK KKK KKK KKK KKK KKK KKK KKKKKKKKKKKKK VARIABLES UDATA OVR Data used for copying const data into RAM Note All the locations in this section can be reused by user programs This can be done by declaring a section with the same name and attribute H i e VARIABLES UDATA OVER in MPASM or H pragma udata overlay VARIABLES in MPLAB C num init RES 2 Number of entries in init table init entry from addr RES 2 ROM address to copy const data from init entry to addr RES 2 RAM address to copy const data to init entry size RES 2 Number of bytes in each init section 2 init entry index RES Used to index through array of init data KKK KK KKK KKK KKK KKK KK KKK KKK KKK KKK KK KKK KKK KKK KKK kckckckckckckckck kckckck ERKAK _c
143. section File Formats MPLINK is comprised of four executables the shell program mplink exe the actual linker mplink exe a COFF to COD file translater mp2cod exe and a COD to HEX file translater mp2hex exe Additional software tools are distributed with MPLINK These tools include a librarian mplib exe a COFF file disassembler mpdis exe a COFF dump utility mpcoff exe and a COD dump utility mpcod exe y 9 A N U A 1997 Microchip Technology Inc DS33014F page 81 MPASM USER S GUIDE with MPLINK and MPLIB Notes DS33014F page 82 O 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Chapter 2 Usage Command Line mplink cmdfile objfile libfile option cmdfile isthe name of a linker command file All linker command files must have the extension Ikr objfile isthe name of an assembler or compiler generated object file All object files must have the extension o libfile is the name of a librarian created library file All library files must have the extension lib option isa linker command line option described below Table 2 1 Linker Command Line Options Option Description o filename specify output file filename default is a out m filename create map file filename L pathlist semi colon delimited list of directories to search for library obj
144. supplied to the macro The values assigned to these arguments at the time the macro is invoked will be substituted wherever the argument name occurs in the body of the macro The body of a macro may be comprised of MPASM directives PICmicro MCU assembly instructions or MPASM Macro Directives LOCAL for example Refer to Chapter 3 MPASM continues to process the body of the macro until an EXITM or ENDM directive is encountered Note Forward references to macros are not permitted Macro Directives There are directives that are unique to macro definitions They cannont be used out of the macro context refer to Chapter 3 for details concerning these directives MACRO LOCAL EXITM ENDM DS33014F page 66 O 1997 Microchip Technology Inc Chapter 5 When writing macros you can use any of these directives PLUS any other directives supported by MPASM Note The previous syntax of the dot format for macro specific directives is no longer supported For compatibility reasons old ASM17 code that use this format will assemble by MPASM but as mentioned before you are encouraged to write new code based on the constructs defined within this document to ensure upward U o mb 3 gt O compatibility with MPASM Text Substitution String replacement and parsing patterns may appear within the body of a macro Command Description lt arg gt Substitute the a
145. tch An unsupported switch was specified Refer to Usage for a list of supported command line options library filename is required All commands require a library filename All library filenames must end with lib invalid object filename All object filenames must end with o Library File Errors Please refer to the documentation on MPLINK for error messages associated with library files COFF File Errors Please refer to the documentation on MPLINK for error messages associated with COFF files DS33014F page 100 O 1997 Microchip Technology Inc MPASM USER S GUIDE MICROCHIP with MPLINK and MPLIB Appendix A Hex File Formats Introduction MPASM is capable of generating several different hex file formats Highlights Intel Hex Format INHX8M for standard programmers Intel Split Hex Format INHX8S for ODD EVEN ROM programmers Intel Hex 32 Format INHX32 for 16 bit core programmers Hex File Formats Intel Hex Format HEX This format produces one 8 bit hex file with a low byte high byte combination Since each address can only contain 8 bits in this format all addresses are doubled This file format is useful for transferring PICmicro series code to PRO MATESII PICSTART and third party PlCmicro programmers Each data record begins with a 9 character prefix and ends with a 2 character checksum Each record has the following format BBAAAATTHHHH HHHCC where BB is a two
146. ted Processor type is undefined Code is being generated before the processor has been defined Note that until the processor is defined the opcode set is not known Unknown processor The selected processor is not a valid processor Hex file format INHX32 required An address above 32K was specified For example specifying the configuration bits on the PIC17CXX family Illegal hex file format An illegal hex file format was specified in the LIST directive Macro name missing A macro was defined without a name O 1997 Microchip Technology Inc DS33014F page 111 MPASM USER S GUIDE with MPLINK and MPLIB 136 137 138 139 140 141 142 143 144 145 146 147 148 149 Duplicate macro name A macro name was duplicated Macros nested too deep The maximum macro nesting level was exceeded Include files nested too deep The maximum include file nesting level was exceeded Maximum of 100 lines inside WHILE ENDW A WHILE ENDW can contain at most 100 lines WHILE must terminate within 256 iterations A WHILE ENDW loop must terminate within 256 iterations This is to prevent infinite assembly WHILEs nested too deep The maximum WHILE ENDW nesting level was exceeded IFs nested too deep The maximum IF nesting level was exceeded Illegal nesting Macros IF s and WHILE s must be completely nested they cannot overlap If you have an IF within a WHILE loop the ENDIF must come before the EN
147. tem Requirements MPASM will run on any PC AT or compatible computer running DOS v5 0 or greater MPASM for Windows requires Windows 3 1 or greater No special display or ancillary devices are required Warranty Registration Installation Note Upon receiving the diskette you should complete and return the Warranty Registration Card enclosed with the disk and mail it promptly Doing so will help to ensure that you receive product updates and notification of interim releases that become available MPASM for Windows is installed through the MPLAB installation procedure For details refer to the MPLAB User s Guide Compatibility Issues MPASM is compatible with all Microchip development systems currently in production This includes MPLAB SIM PICmicro MCU discrete event simulator MPLAB PICMASTER PICmicro MCU Universal In Circuit Emulator PRO MATE the Microchip Universal Programmer and PICSTART Plus the Microchip low cost development programmer MPASM supports a clean and consistent method of specifying radix see Chapter 5 You are encouraged to develop new code using the methods described within this document even though certain older syntaxes may be supported for compatibility reasons DS33014F page 10 O 1997 Microchip Technology Inc Chapter 1 Customer Support Microchip endeavors at all times to provide the best service and responsiveness possible to its customers Technical support questions s
148. tion Function lbff BCF f b Bit clear f 0 gt f b lbff BSF b Bit set f 1 gt f b 1bff BTFSC b Bit test skip if clear skip if f b 0 lbff BTFSS b Bit test skip if set skip if f b 1 Table E 11 PIC16C5X PIC16CXX Special Instruction Mnemonics 5 EN Equivalent Status Mnemonic Description Operation s ADDCF f d Add Carry to File BTFSC 3 0 Z INCF fd ADDDCF f d Add Digit Carry to File BTFSC 3 1 Z INCF fd B Branch GOTO k BC Branch on Carry BTFSC 3 0 GOTO k BDC k Branch on Digit Carry BTFSC 3 1 GOTO k DS33014F page 134 1997 Microchip Technology Inc Appendix E Quick Reference Table E 11 PIC16C5X PIC16CXX Special Instruction Mnemonics Mnemonic Description Equivalent Status p Operation s BNC k Branch on No Carry BTFSS 3 0 GOTO k BNDC k Branch on No Digit Carry BTFSS 3 1 GOTO k BNZ k Branch on No Zero BTFSS 3 2 GOTO k BZ k Branch on Zero BTFSC 3 2 GOTO k CLRC Clear Carry BCF 3 0 CLRDC Clear Digit Carry BCF 3 1 CLRZ Clear Zero BCF 3 2 LCALL k LGOTO k MOVEW f Move File to W MOVF f 0 Z NEGF f d Negate File COMF f 1 Z INCF f d SETC Set Carry BSF 3 0 SETDC Set Digit Carry BSF 3 1 SETZ Set Zero BSF 3 2 SKPC Skip on Carry BTFSS 3 0 SKPDC Skip on Digit Carry BTFSS 3 1 SKPNC Skip on No Carry BTFSC 3 0 SKPNDC Skip on No Digit Carry BTFSC 3 1 SKPN
149. titution Local Symbols Recursive Macros Macro Usage Examples Terms Macro A macro is a collection of assembler instructions that are included in the assembly code when the macro name is encountered in the source code Macros must be defined before before they are used forward references to macros are not allowed All statements following the MACRO directive see Chapter 3 are part of the macro definition Labels used within the macro must be local to the macro so the macro can be called repetitively 1997 Microchip Technology Inc DS33014F page 65 MPASM USER S GUIDE with MPLINK and MPLIB Macro Syntax Local Label A local label is one that is defined with the LOCAL directive see Chapter 3 These labels are particular to a given instance of the macro s instantiation In other words the symbols and labels that are declared as local are purged from the symbol table when the ENDM macro is encountered Recursion This is the concept that a macro having been defined can call itself Great care should be taken when writing recursive macros it is easy to get caught in an infinite loop where there will be no exit from the recursion Nesting Depth Macros can be nested to sixteen levels deep MPASM macros are defined according to the following syntax lt label gt macro arglo afg2 lt arg0 gt endm where 1abel is a valid MPASM label and lt arg gt is any number of optional arguments
150. ude alpha characters and numbers 0 1 9 Command Line Interface Command Line Interface refers to executing a program with options Executing MPASM with any command line options or just the file name will invoke the assembler In the absence of any command line options a prompted input interface shell will be executed Shell The MPASM shell is a prompted input interface to the macro assembler There are two MPASM shells one for the DOS version and one for the Windows version O 1997 Microchip Technology Inc DS33014F page 13 MPASM USER S GUIDE with MPLINK and MPLIB Command Line Interface MPASM can be invoked through the command line interface as follows MPASM lt Option gt lt Option gt file name or MPASMWIN lt Option gt lt Option gt lt filename gt Where lt Option gt refers to one of the command line options file name is the file being assembled For example if test asm exists in the current directory it can be assembled with following command MPASM e 1 test The assembler defaults noted in Table can be overridden with options e option enables the option e lt option gt enables the option e option disables the option option filename if appropriate enables the option and directs the output to the specified file If the filename is omitted the appropriate shell interface is invoked Table 2 1 Assembler Command Line O
151. ul Korea Tel 82 2 554 7200 Fax 82 2 558 5934 Shanghai Microchip Technology RM 406 Shanghai Golden Bridge Bldg 2077 Yan an Road West Hong Qiao District Shanghai PRC 200335 Tel 86 21 6275 5700 Fax 86 21 6275 5060 Singapore Microchip Technology Taiwan Singapore Branch 200 Middle Road 3107 02 Prime Centre Singapore 188980 Tel 65 334 8870 Fax 65 334 8850 Taiwan R O C Microchip Technology Taiwan 10F 1C 207 Tung Hua North Road Taipei Taiwan ROC Tel 886 2 717 7175 Fax 886 2 545 0139 EUROPE United Kingdom Arizona Microchip Technology Ltd Unit 6 The Courtyard Meadow Bank Furlong Road Bourne End Buckinghamshire SL8 5AJ Tel 44 1628 851077 Fax 44 1628 850259 France Arizona Microchip Technology SARL Zone Industrielle de la Bonde 2 Rue du Buisson aux Fraises 91300 Massy France Tel 33 1 69 53 63 20 Fax 33 1 69 30 90 79 Germany Arizona Microchip Technology GmbH Gustav Heinemann Ring 125 D 81739 M chen Germany Tel 49 89 627 144 0 Fax 49 89 627 144 44 Italy Arizona Microchip Technology SRL Centro Direzionale Colleoni Palazzo Taurus 1 V Le Colleoni 1 20041 Agrate Brianza Milan Italy Tel 39 39 6899939 Fax 39 39 6899883 JAPAN Microchip Technology Intl Inc Benex S 1 6F 3 18 20 Shinyokohama Kohoku Ku Yokohama shi Kanagawa 222 Japan Tel 81 45 471 6166 Fax 81 45 471 6122 9 24 97 ra mr Li LEA Per ILE reer a A By Wl vm 1505 6061 REGISTE
152. ulator x Don t care location i Table pointer control i 0 Do not change i21 Increment after instruction execution p Peripheral register file address 0x00 to Ox1f t Table byte select t 0 Perform operation on lower byte t 1 Perform operation on upper byte PH PL Multiplication results registers PIC16C5X Instruction Set The PIC16C5X Microchip s base line 8 bit microcontroller family uses a 12 bit wide instruction set All instructions execute in a single instruction cycle unless otherwise noted Any unused opcode is executed as a NOP The instruction set is grouped into the following catagories Table E 5 PIC16C5X Literal and Control Operations Hex Mnemonic Description Function Ekk ANDLW k AND literal and W k AND W gt W 9kk CALL k Call subroutine PC 1 gt TOS k gt PC 004 CLRWDT Clear watchdog timer 0 gt WDT and Prescaler if assigned Akk GOTO k Goto address kis nine bits k gt PC 9 bits Dkk IORLW k Incl OR literal and W k OR W gt W Ckk MOVLW k Move Literal to W kW 002 OPTION Load OPTION Register W OPTION Register 8kk RETLW k Return with literal in W k gt W TOS gt PC 003 SLEEP Go into Standby Mode 0 WDT stop oscillator 00f TRIS f Tristate port f W gt I O control reg f Fkk XORLW k Exclusive OR literal and W k XOR W gt W 1997 Microchip Technology Inc DS33014F page 131 MP
153. uninitialized data lt name gt udata_shr lt address gt O 1997 Microchip Technology Inc DS33014F page 127 MPASM USER S GUIDE with MPLINK and MPLIB Table E 2 MPASM Command Line Options Option Default Description N A Displays the MPASM Help Panel INHX8M Generate absolute COD and hex output directly from assembler a lt hex format gt where lt hex format gt is one of INHX8M INHX8S INHX32 Enables Disables case sensitivity Define a text string substitution d lt label gt lt value gt enable disable set path for error file le Enable le Enable le Disable e lt path gt error file Enables sets path N A Displays the MPASM Help Panel Enable disable set path for list file Enable N Enable A Disable Al lt path gt list file Enables sets path Enable Disable macro expansion Off Enable disable set path for object file o Enable 0 Enable o Disable o lt path gt object file Enables sets path None Set the processor type p lt processor_type gt Where lt processor_type gt is a member of the PICmicro MCU family For example PIC16C54 Off Enable Disable Quiet Mode suppress screen output Hex Defines default radix r lt radix gt where radix is one of HEX DEC OCT Set list file tab size Set message level w lt value gt Where value is 0 all messages 1 e
154. ures that all addresses are resolved Any function in the various input modules that attempts to access data or call a routine that has not been allocated or created will cause MPLINK to generate an error MPLINK also generates the symbolic information for debugging your application with MPLAB and produces the HEX object file for the executable PICmicro code used by device programmers MPLINK is executed after assembling or compiling relocatable object modules with MPASM and or MPLAB C File Formats MPLINK uses and generates various different file types MPLINK accepts three types of input files object files library files and linker command files The object files and library files used by MPLINK are COFF files which support relocatable object modules and robust symbolic debugging The linker command files used by MPLINK are ASCII text files MPLINK generates five types of output files COFF Output File a binary file containing the relocated input sections no unresolved externals robust symbolic debug info and all the necessary information to generate a COD listing and hex file COD File a binary file containing debug information This is the debug format currently supported by MPLAB MapFile an ASCII text file which lists information about sections and symbols Listing File an ASCII text file which mixes the source code with disassembled code Hex File a file used for device programming The linker first
155. ve to declare the existence of these labels An example of using the GLOBAL and EXTERN directives is shown below Relocatable Code Defining Module UDATA InputGain RES ds OutputGain RES 1 GLOBAL InputGain OutputGain CODE Filter GLOBAL Filter Filter code Relocatable Code Referencing Module EXTERN InputGain OutputGain Filter UDATA Reading RES I CODE MOVLW GAIN1 MOVWF InputGain MOVLW GAIN2 MOVWF OutputGain MOVF Reading W CALL Filter DS33014F page 60 O 1997 Microchip Technology Inc Chapter 4 Paging and Banking Issues In many cases RAM allocation will span multiple banks and executable code will span multiple pages In these cases it is necessary to perform proper bank and page set up to properly access the labels However since the absolute addresses of these variable and address labels are not known at assembly time itis not always possible to place the proper code in the source flle For these situations two new directives BANKSEL and PAGESEL have been added These directives instruct the linker to generate the correct bank or page selecting code for a specified label An example of how code should be converted is shown below Absolute Code LIST P 12C509 f n gt S include P12C509 INC Varl EQU H 10 Var2 EQU H 30 OVLW InitialValue BCF FSR 5 OVWF Varl BSF FSR 5 OVWF Var2 BSF STATUS PAO CALL Subroutine Subroutine CLRW In P
156. vf init entry size W iorwf init entry size 1 W btfsc STATUS Z goto dec num init DS33014F page 144 1997 Microchip Technology Inc Appendix F Example Initialization Code H Set up the destination address for the data in the FSR so we are prepared to copy data using indirect addressing BANKSEL init entry to addr movf init entry to addr W movwf FSR a Read a single data byte by doing a long jump into the section in program memory _Dummy1 _Dummy2 goto _Dummy2 movf init entry from addr 1 W movwf PCLATH movf init entry from addr W movwf PCL call _Dummy1 Puts return address on stack H Now write the data to RAM using indirect addressing movf init entry to addr 1 1 Check if upper portion of btfss STATUS Z address is non zero If so then bsf STATUS IRP set the IRP bit Otherwise bcf STATUS IRP Clear the IRP bit movwf INDF After copying one entry we need to incf incf btfsc ds 2 34 Increment the program memory source address Increment the data memory destination address Decrement the init entry size BANKSEL init entry from addr init entry from addr 1 btfsc STATUS C incf init_entry_from_addr 1 1 BANKSEL init_entry_to_addr Increment the address init entry to adadr 1 init entry to addr STATUS C incf init entry to addr 1 1 BANKSEL init entry size Decrement the count movf init entry size l1 init entry size btfsc STATUS Z decf init ent
157. where objfile libfile is either an object or library file Note more than one object or library file can be specified in a single FILES directive Example To specify that the object module main o be linked with the library file math lib the following line should be added to the linker command file FILES main o math lib INCLUDE Directive The following directive includes an additional linker command file INCLUDE cmdfile where cmdfile is the name of the linker command file to include Example To include the linker command file named mylink Ikr the following line should be added to the linker command file INCLUDE mylink lkr DATABANK CODEPAGE SHAREBANK Directives The following directives define portions of the target s memory by specifiying a name for a block of memory its starting address and its ending address DATABANK NAME memName START addr END addr PROTECTED CODEPAGE NAME memName START addr END addr PROTECTED FILL fillValue SHAREBANK NAME memName START addr END addr PROTECTED where memName is any ASCII string used to identify a DATABANK CODEPAGE or SHAREBANK addr is a decimal or hexadecimal number specifying an address DS33014F page 86 O 1997 Microchip Technology Inc Chapter 3 Command File fillValue is a 16 bit quantity which fills any unused portion of a memory block Only CODEPAGE directives may have a FILL attribute The DATABANK
158. xpr Description The value of lt expr gt is assigned to lt label gt Example four equ 4 assigned the numeric value of 4 to label four See Also SET ERROR Issue an Error Message Syntax error text string Description text string is printed in a format identical to any MPASM error message text string may be from one to eighty characters Example error checking macro argi if argl gt 55 if arg is out of range error error checking 01 arg out of range endif DS33014F page 36 O 1997 Microchip Technology Inc Chapter 3 5 D endm e See Also MESSG ERRORLEVEL Set Message Level gt Syntax S errorlevel 0 1 2 msgnum Description Sets the types of messages that are printed in the listing file and error file Setting Affect 0 Messages warnings and errors printed T Warnings and errors printed 2 Errors printed lt msgnum gt Inhibits printing of message lt msgnum gt lt msgnum gt Enables printing of message lt msgnum gt The values for msgnum are in Appendix C Error messages cannot be disabled The setting of O 1 or 2 overrides individual message disabling or enabling Example errorlevel Ly 202 See Also LIST EXITM Exit from a Macro Syntax exitm Description Force immediate return from macro expansion during assembly The effect is the same as ifan ENDM directive had been encountered Exam
159. y of the the following errors are generated Unable to find section name in string table Unable to find symbol name in string table Unable to find aux file name in string table Could not find section name secName in string table Could not find symbol name symName in string table Coff file filename symbol xx has an invalid n scnum Coff file filename symbol xx has an invalid n offset Coff file filename section xx has an invalid s offset Coff file filename has relocation entries but an empty symbol table Coff file filename section secName reloc xx has an invalid r symndx Coff file filename symbol xx has an invalid x tagndx or x_endndx Coff file filename section secName line xx has an invalid srcndx Coff file filename section secName line xx has an invalid fcnndx Coff file filename cScnHdr size cScnNum size Could not open Coff fi Coff file filename cou Coff file filename cou e filename for reading d not read file header d not read optional file header Coff file filename missing optional file header Coff file filename cou Coff file filename cou Coff file filename cou Coff file filename cou Coff file filename cou Coff file filename cou Coff file filename cou Could not open Coff fi Coff file filename cou Coff file filename cou Coff file filename cou d not read string table length d not read string t

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