RC56D USB Integrated V.90/K56flex Modem Device Sets with USB
Contents
1. Pins LED3 0 36 37 43 44 were designed to drive LEDs connected directly to VCC The LED driver is too strong causing the device to sink excessive current When all of the LED drivers are turned on at the same time the current sinking capability of the device will be exceeded causing excessive heating and reducing reliability of the device By using a 250 Q resistor in series with each LED to avoid this problem Electrical Characteristics and Timing For R8292 electrical characteristics and timing information refer to Intel 8x931AA 8x931HA Universal Serial Bus Peripheral Controllers Order Number 273108 002 R8292 power consumption is 70 mA active and 40 mA idle MD234 GT conexant 13 RC56D USB Integrated V 90 K56flex Modem Device Sets with USB Interface Worldwide Headquarters 4311 Jamboree Road P O Box C Newport Beach CA 92658 8902 Phone 949 483 4600 Fax 949 483 6375 For more information Call 1 800 854 8099 International information Call 1 949 483 6996 URL Address http www conexant com E Mail Address literature conexant com REGIONAL SALES OFFICES US Northwest Pacific Northwest 3600 Pruneridge Avenue Suite 100 Santa Clara CA 95051 Phone 408 249 9696 Fax 408 249 7113 US Los Angeles 1000 Business Center Circle Suite 215 Thousand Oaks CA 91320 Phone 805 376 0559 Fax 805 376 8180 US Southwest 4350 Von Karman Ave Suite 400 Newport Beach CA 92660 Phone 9492. INC Printed in U S A All Rights Reserved 2 GT conexant MD211 Integrated V 90 K56flex Modem Device Sets with USB Interface RC56D USB System Architecture Hardware Interface A system block diagram is shown in Figure 1 The major interface signals are shown in Figure 2 MODEM DEVICE SET TELEPHONE USB LINE CONTROLLER MICRO TELEPHONE USB UNIT HANDSET CONTROLLER AUDIO INTERFACE UCU UNIT MODEM MCU DATA PUMP INTERFACE R8292 CIRCUIT 80 PIN PQFP MDP 80931AA L2800 l 100 PIN PQFP R6764 1M 128K x 8 RAM 2M 256K x 8 ROM FLASH ROM TELEPHONE LINE TEL HANDSET HEADPHONE SPEAKER MICROPHONE MD234F1 BD Figure 1 Block Diagram RINGWAKE RLY1 OH RLY2 VOICE XTLI RLY3 MUTE CRYSTAL CRYSTAL CIRCUIT CIRCUIT RLY4 CALLID EXTOH z iGS TELEPHONE LINE RINGD vec TELEPHONE LINE TELEPHONE HANDSET AUDIO TELEPHONE is INTERFACE HANDSET yY VDD RIN CIRCUIT SVCC CLKOUT SIKIN pa MICROPHONE TXA1 HEADPHONE WKRESOUT SPEAKER WKRES TXA2 DPIRQ IRQ D j use gt 4 ODER TELIN DATA TELOUT USB MICRO MDP SPKM Ki CONTROLLER CONTROLLER AO A17 RSO RS UNIT UNIT ai 0 RS4 hs MICV ucu MCU MICM DPSEL ROMSEL t i p RESET RAMSEL He VES_ svc 45v a AVDD svc 4
3. to 0 If the binterfaceClass field is not set to OxFF all values are reserved for assignment by USB i i 8 iintertace 10 GT conexant MD211 Integrated V 90 K56flex Modem Device Sets with USB Interface RC56D USB Endpoint Descriptor Each endpoint used for an interface has its own descriptor which contains the information required by the host to determine the bandwidth requirements of each endpoint see Table 6 An endpoint descriptor like an Interface Descriptor is always returned as part of a configuration descriptor The default values are Bulk In 1 07058102100000 Bulk Out 1 07050102100000 Bulk In 2 07058203080064 Bulk Out 2 07050202080000 Table 6 Endpoint Descriptors Offset Fied Size Value Description o bLength Size of this descriptor in bytes bDescriptorType ENDPOINT Descriptor Type bEndpointAddress 1 Endpoint The address of the endpoint on the USB device described by this descriptor The address is encoded as follows Bit 0 3 The endpoint number Bit 4 6 Reserved reset to 0 Bit7 Direction ignored for control endpoints 0 OUT endpoint 1 IN endpoint 3 bmAttributes Bit Map This field describes the endpoints attributes when it is configured using the bConfiguration Value Bit 0 1 Transfer Type 00 Control 01 Isochronous 10 Bulk 11 Interrupt All other bits are reserved 4 1 wMaxPacketSize 2 Number Maximum packet size this endpoint is capable of sending or receiving when this configur
4. Sense input to indicate an overcurrent condition on an external down stream port Active low with an internal pullup NC PO 7 0 VO Address Data Lines Eight bit open drain bidirectional I O lines with Schmitt trigger inputs that represent lower byte of external memory address multiplexed with data Ps o Ready indicate Active tow output to dive READY LED Por has internal pulup Ps o Be indleate Active low output to drive DCD LED Portas intemal putu Pra o BATA maicate Active ow output to dive DATA LED Port has internal putup ae aa MODEMPWRCNTRL Active low output used to control power supply to non USB side of isolation Port has internal pullup m2 MoMRESET Active low ouput used to reset the MGU and MDP This por has an intemal palup Pazo o Address Lines Eigh t port wih internal pulups used for upper byte of extemal memory address FPLLSEL 1 Phase locked Loop Select Connect to VOC for 12MHZ Xtal and T2MBpS ful speed USB rate Psens o Program Store Enable Read signal output Asseted for read accesses to external program memory PROF o Read Assented for read accesses to extemal datamemay RST Reset Reset input to the chip Holding this pin high for 64 oscillator periods while the oscillator is running resets the device The port pins are driven to their reset conditions when a voltage greater than VIH1 is applied whether or not the oscillator is running This pin has an internal pulldown re
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6. 5V VAA SVCC 5V EXTERNAL SVCC 5V PNS 2M 256K X 8 VDD ROM FLASH ROM ROMSEL A0 A16 1M 128K X 8 SP MODEL RAM NON SP MODEL RAMSEL MD234F2 IF Figure 2 Hardware Interface Signals MD234 GT lt onexanr RC56D USB Integrated V 90 K56flex Modem Device Sets with USB Interface R8292 Signal Pin Assignments and Descriptions The R8292 68 pin PLCC signal pin assignments are shown in Figure 3 The R8292 68 pin PLCC signals are described in Table 2 Reserved NC Reserved NC Q Zwo SHANMYTHONHNDOH WWD NUNANANANNANNNDOTINVHNYN oaaanaaaaS gt sSuctauws MDROonontranr PO 7 Reserved NC P0 6 Reserved NC P0 5 Reserved NC P0 4 Reserved NC P0 3 VCC P0 2 DPO PO 1 DMO P0 0 ECAP VSS VSSP VCC VCCP P3 0 VSS P3 1 SOF Reserved NC P3 2 INTO Reserved NC P3 3 INT1 VSSP P3 4 Reserved NC P3 5 Reserved NC WR LEDO RD P1 0 T2 P1 1 T2EX P1 2 P1 3 P1 4 P1 5 P1 6 P1 7 LED3 LED2 XTAL1 XTAL2 AVCC MD234F3 PO R8292 68PLCC Figure 3 R8292 68 Pin PLCC Pin Signals 4 GT conexant MD211 Integrated V 90 K56flex Modem Device Sets with USB Interface RC56D USB Table 2 R8292 68 Pin PLCC Pin Signal Descriptions ALE Address Latch Enable ALE signals the start of an external bus cycle and indicates that valid address information is available on lines A15 8 and AD7 0 An external latch can use ALE to demultiplex the address from the address data b
7. RC56D USB Integrated V 90 K56flex Se C CONEXANT Modem Device Sets with USB Interface for Desktop Applications Introduction The CONEXANT RC56D Modem Device Set supports the USB Universal Serial Bus as described by the Universal Serial Bus Specification Revision 1 0 USB provides a flexible interconnect between a PC and a wide range of peripherals such as to a CONEXANT modem device set The CONEXANT RC56D family devices in conjunction with the R8292 USB controller provide a complete USB modem solution The supported modem feature set for the USB modem solution is the same as the standard RC56D parallel host interface device set see RC56D and RC336D Integrated V 90 K56flex V 34 Modem Device Set for Desktop Applications Data Sheet Order No MD211 The modem models which include the R8292 UCU USB Controller Unit in 68 PLCC are listed in Table 1 Hardware A complete accelerator kit implementing the USB solution is offered as Perth AK56 D540 This design consists of the RC56D parallel host interface device set and the R8292 USB Controller Unit UCU The R8292 operates with a 12 MHz crystal A 32K x 8 150 ns EEPROM is required for USB controller firmware Additionally one latch one transistor and two bus transceivers are required The R8292 USB Controller is based on the MCS 51 microcontroller It is a hubless USB peripheral controller that supports suspend resume modes and isochronous non isochr
8. SB These codes are qualified by the value of the bDeviceClass field If the bDeviceClass field is reset to 0 this field must also be reset to 0 If the bDeviceClass field is not set to OxFF all values are reserved for assignment by USB Protocol code assigned by USB These codes are qualified by the value of the bDeviceClass and the bDeviceSubClass fields If a device supports class specific protocols on a device basis as opposed to an interface basis this code identifies the protocols that the device uses as defined by the specification of the device class If this field is reset to 0 the device does not use class specific protocols on a device basis However it may use class specific protocols on an interface basis If this field is set to OxFF the device uses a vendor specific protocol on a device basis Maximum packet size for endpoint zero only 8 16 32 or 64 are valid independently bMaxPacketSizeO If this field is set to a value between 1 and OxFE the device supports different class specifications on different interfaces and the interfaces may not operate independently This value identifies the class definition used for the aggregate interfaces For example a CD ROM device with audio and digital data interfaces that require transport control to eject CDs or start them spinning If this field is set to OxFF the device class is vendor specific idProduct iSerialNumber bNumConfigurations 8 GT cone
9. ation is selected For isochronous endpoints this value is used to reserve the bus time in the schedule required for the per frame data payloads The pipe may on an ongoing basis actually use less bandwidth than that reserved The device reports if necessary the actual bandwidth used via its normal non USB defined mechanisms For interrupt bulk and control endpoints smaller data payloads may be sent but will terminate the transfer and may or may not require intervention to restart Refer to Chapter 5 for more information binterval 1 Interval for polling endpoint for data transfers Expressed in milliseconds This field is ignored for bulk and control endpoints For isochronous endpoints this field must be set to 1 For interrupt endpoints this field may range from 1 to 255 MD234 GT conexant 11 RC56D USB Integrated V 90 K56flex Modem Device Sets with USB Interface Enumeration The R8292 enumeration process consists of the following steps 1 Get device descriptor The host requests and reads the device descriptor to determine maximum packet size 2 Set address The host sends the R8292 s function address in a data packet using function endpoint 0 Device firmware interprets this data 3 Get device descriptor The host requests and reads the device descriptor to determine such information as device class USB Specification compliance level maximum packet size for endpoint 0 vendor id product id Etc 4 Get configura
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11. in this specific configuration when the device is fully operational Expressed in 2 mA units i e 50 100 mA Note A device configuration reports whether the configuration is bus powered or self powered Device status reports whether the device is currently self powered If a device is disconnected from its external power source it updates device status to indicate that it is no longer self powered A device may not increase its power draw from the bus when it loses its external power source beyond the amount reported by its configuration If a device can continue to operate when disconnected from its external power source it continues to do so If the device cannot continue to operate it fails operations it can no longer support Host software may determine the cause of the failure by checking the status and noting the loss of the device s power source MD234 GT conexant 9 RC56D USB Integrated V 90 K56flex Modem Device Sets with USB Interface Interface Descriptor An interface descriptor describes a specific interface provided by the associated configuration see Table 5 It is always returned as part of a configuration descriptor An interface descriptor never includes endpoint zero in the number of endpoints Table 5 Interface Descriptors offset Field Size Value Defaut Description O oo bLength 1 Number 09 Size of this descriptor in bytes bDescriptorType INTERFACE Descriptor Type 2 biInte
12. l quality will suffer This condition can be seen on an oscilloscope as excessive overshoot and undershoot and will introduce errors and lower throughput Pullup Resistor Requirement The USB specification requires a pullup resistor to allow the host to identify which devices are low speed and which devices are high speed in order to communicate at the appropriate data rate For R8292 add a 1 5K Q pullup to 3 0V 3 6V such as pin 53 ECAP These pullup resistors should be placed as close to the R8292 as possible If ECAP is used a 1 uF capacitor should be connected between ECAP and GND Noise Considerations The R8292 high speed logic can produce noise spikes on power and signal lines Decoupling capacitors and transient absorbers will keep noise to a minimum Connect 0 1uF bypass caps between VCC AVCC and each VSS pin Noise spikes on XTAL1 and XTAL2 can disrupt the timing of the R8292 Place the crystal and capacitors near the device and connect with short direct traces This will help minimize coupling between other digital circuits and the crystal Additionally place guard rings around the oscillator circuitry and ground the metal crystal case Power on Reset To automatically generate a reset when power is applied connect the RST pin to VCC through a 0 33 uF capacitor When VCC is applied the RST pin rises to VCC and does not decay below the threshold before the crystal stabilizes plus two machine cycles Excessive LED Current
13. n one of two ways Class and vendor specific descriptors that are related to standard descriptors are returned in the same data buffer as the standard descriptor If a class or vendor specific descriptor is not related to a standard descriptor it is returned using class or vendor specific requests Device Descriptor A device descriptor describes general information about a USB device which applies globally to the device and all of the device s configurations see Table 3 A USB device has only one device descriptor Vendor ID Product ID and Device Release Number can be changed The Manufacturer Name Product Name and Serial Number can also be customized MD234 GT conexant 7 RC56D USB Integrated V 90 K56flex Modem Device Sets with USB Interface Table 3 Device Descriptors onset ried Sze vawe Detaut pesoi o oeron i Number 12 Size orinis aesorporin oyes SSCS i foeon 1 foose o 0evce beseectpe ooo bcdUSB 0100 USB Specification Release Number in Binary Coded Decimal i e 2 10 is 0x210 This field identifies the release of the USB Specification that the device and its descriptors are compliant with bDeviceClass Class code assigned by USB If this field is reset to 0 each interface within a configuration bDeviceSubClass SubClass l l specifies its own class information and the various interfaces operate L bDeviceProtocol aE 8e i 10 2 m i is i 6 rel Subclass code assigned by U
14. o Part No 3 Host DSVD V 80 RC56D SP USB DS56 L122 011 12800 38 R6764 61 R8292 11 RC56D USB DS56 L122 021 12800 38 R6764 63 R829211 oy a Notes 1 Model options D Downloadable SP Speakerphone USB USB interface Supported functions Y Supported Not supported AudioSpan Analog simultaneous voice and data DSVD Digital simultaneous voice and data Fax Cl 1 and 2 Fax Class 1 1 0 and Fax Class 2 support FDSP Full duplex speakerphone Voice TAM Voice and telephone answering machine support handset support requires SP model R8292 is the CONEXANT internal part number for the Intel 80931AA Information provided by CONEXANT SYSTEMS INC is believed to be accurate and reliable However no responsibility is assumed by CONEXANT for its use nor any infringement of patents or other rights of third parties which may result from its use No license is granted by implication or otherwise under any patent rights of CONEXANT other than for circuitry embodied in CONEXANT products CONEXANT reserves the right to change circuitry at any time without notice This document is subject to change without notice K56flex is a trademark of CONEXANT SYSTEMS INC and Lucent Technologies CONEXANT What s Next in Communications Technologies MNP 10EC and ConfigurACE are trademarks of CONEXANT SYSTEMS INC MNP is a trademark of Compaq Computer Corporation MGS is a registered trademark of Intel Corporation 1998 CONEXANT SYSTEMS
15. onous transfers Firmware Firmware for the R8292 controller is provided in object form however vendor specific descriptors can be customized with a supplied utility Vendor ID Product ID Device Release Number Manufacturer Name Product Name and Serial Number can all be modified Drivers A complete set of software drivers is provided for Windows 98 and Windows 95 OSR 2 1 support Sample INF files are also provided Data Sheet Features e All features supported by the RC56D family see data sheet Order No MD211 e Universal Serial Bus Specification Rev 1 0 compliant e Three function endpoint pairs with corresponding transmit receive FIFO pairs e Automatic transmit receive FIFO management e USB full speed 12Mbps e USB low speed 1 5Mbps e Reset separation e Four LED driver outputs e On chip phase locked loop PLL e On chip USB transceivers e 256 bytes on chip Data RAM e Suspend Resume e Vendor specific descriptors e Windows 98 support e Windows 95 OSR 2 1 support e Extension pickup remote hang up detection e Line in use detection Order No MD234 Rev 1 December 18 1998 RC56D USB Integrated V 90 K56flex Modem Device Sets with USB Interface Table 1 Modem Models and Functions Model Order Part Numbers Supported Functions Marketing Device Set MCU MDP UCU V 90 K56flex Data V 34 Fax FDSP AudioSpan Model Number Order Number 80 PQFP 100 PQFP 68 PLCC Fax CI 1 and 2 Voice TAM Part No Part N
16. polis Cedex Europe South Tour GAN Cedex 13 92082 Paris La D fense 2 France Phone 33 1 49 06 39 80 Fax 33 1 49 06 39 90 APAC Headquarters 1 Kim Seng Promenade 09 01 East Tower Great World City Singapore 237994 Phone 65 737 7355 Fax 65 737 9077 Australia Suite 603 51 Rawson Street Epping NSW 2121 Australia Phone 61 2 9869 4088 Fax 61 2 9869 4077 China Shanghai Representative Office LT Square Building Suite 3002 500 Chengdu North Road Shanghai 200003 P R C Phone 86 21 6361 2515 Fax 86 21 6361 2516 Hong Kong 13th Floor Suites 8 10 Harbour Centre 25 Harbour Road Wanchai Hong Kong Phone 852 2 827 0181 Fax 852 2 827 6488 C 2e India Regional Office South Asia Capital Trust House 47 Community Centre Friends Colony New Delhi 110 065 India Phone 91 11 692 4780 Fax 91 11 692 4712 Korea Room No 1508 Korea Textile Centre Building 944 31 Daechi 3dong Kangnam P O Box 2037 Kangnam ku Seoul Korea Phone 82 2 565 2880 Fax 82 2 565 1440 Taiwan Headquarters Room 2808 International Trade Bldg 333 Keelung Road Section Taipei Taiwan 10548 ROC Phone 886 2 2720 0282 Fax 886 2 2757 6760 Japan Headquarters Shimomoto Bldg 1 46 3 Hatsudai Shibuya ku Tokyo 151 Japan Phone 81 3 5371 1520 Fax 81 3 5371 1501 SOUD981 214 cCcONEXAN T What s next in communications technologies sr puR This datash
17. rfaceNumber 1 Number Number of interface Zero based value identifying the index in the array of concurrent interfaces supported by this configuration bAlternateSetting 1 Number Value used to select alternate setting for the interface identified in the prior field bNumEnapoints Number of endpoints used by this interface excluding endpoint zero If this value is 0 this interface only uses endpoint zero binterfaceClass Class code assigned by USB If this field is reset to 0 the interface does not belong to any USB specified device class If this field is set to OxFF the interface class is vendor specific All other values are reserved for assignment by USB biInterfaceProtocol Protocol Protocol code assigned by USB These codes are qualified by the value of the binterfaceClass and the binterfaceSubClass fields If an interface supports class specific requests this code identifies the protocols that the device uses as defined by the specification of the device class If this field is reset to 0 the device does not use a class specific protocol on this interface If this field is set to OxFF the device uses a vendor specific protocol for this interface Index of string descriptor describing this interface ea ae W W binterfaceSubClass 1 SubClass Subclass code assigned by USB These codes are qualified by the value of the binterfaceClass field If the binterfaceClass field is reset to 0 this field must also be reset
18. sistor which allows the device to be reset by connecting a capacitor between this pin and VCC Asserting RST when the chip is in idle mode or powerdown mode returns the chip to normal operation SOF P3 1 Start of Frame Start of frame pulse Active low Asserted for 8 states when frame timer is locked to USB frame timing and SOF token or artificial SOF is detected NC MD234 GT conexant 5 RC56D USB Integrated V 90 K56flex Modem Device Sets with USB Interface Table 2 R8292 68 Pin PLCC Pin Signal Descriptions Cont d wre fo wete wie signal cutputo extemal memoy O oOo Oscillator Amplifier Input When implementing the on chip oscillator connect the external crystal or ceramic resonator across XTAL1 and XTAL2 If an external clock source is used connect it to this pin Oscillator Amplifier Output When implementing the on chip oscillator connect the external crystal or ceramic resonator across XTAL1 and XTAL2 If an external oscillator is used leave XTAL2 unconnected 6 GT conexant MD211 Integrated V 90 K56flex Modem Device Sets with USB Interface RC56D USB USB General Operation Descriptors USB devices report their attributes using descriptors A descriptor is a data structure with a defined format which begins with a byte wide field that contains the total number of bytes in the descriptor followed by a byte wide field that identifies the descriptor type Class and vendor specific descriptors may be returned i
19. tion descriptor The host requests and reads the device configuration descriptor to determine such information as the number of interfaces and endpoints endpoint transfer type packet size and direction power source maximum power etc When the host requests the configuration descriptor all related interface and endpoint descriptors are returned 5 Set configuration The host assigns a configuration value to the device to establish the current configuration Endpoint Pairs Data transfers with the host are made to from endpoint pairs on the USB module The R8292 provides three function endpoint pairs as follows Table 7 Endpoint Pairs Endpoint Pair Transmit FIFO Receive FIFO USB Data Transfer Types Function Endpoint 0 8 bytes 8 bytes Function Endpoint 1 16 bytes 16 bytes Control Interrupt Bulk lsochronous Function Endpoint 2 8 bytes 8 bytes Control Interrupt Bulk 12 GT conexant MD211 Integrated V 90 K56flex Modem Device Sets with USB Interface RC56D USB Design Considerations In addition to the design considerations found in the RC56D RC336D Designer s Guide Order No 1154 the following should be taken into account when designing a USB solution Series Resistor Requirement for Impedance Matching Per USB rev 1 0 specification the impedance of the differential driver must be between 29 Q and 33 should be connected to each USB line i e on D and D If the USB line is improperly terminated or not matched then signa
20. us AVCC Analog VCC AVCC input for the phase locked loop circuitry DMO DPO 1 0 USB Port 0 DPO and DMO are the differential data plus and data minus signals of USB port 0 the upstream differential port These lines do not have internal pullup resistors Provide an external 1 5 KQ pullup resistor at DPO If DPO is not pulled high a continuous SEO USB reset will be applied to these inputs causing the 8x931 to stay in reset EA External Access Directs program memory accesses to on chip or off chip code memory For EA strapped to ground all program memory accesses are off chip For EA strapped to VCC program accesses on chip ROM if the address is within the range of the on chip ROM otherwise the access is off chip The value of EA is latched at reset For devices without on chip ROM EA must be strapped to ground ECAP External Capacitor Connect a 2 2 uF capacitor between this pin and VSS to ensure proper operation of the differential line drivers FSSEL hie Full Speed Select Connect to VCC for 12MHz Xtal and 12Mbps full speed USB rate INT1 HINT Host bus interrupt input is set high by MCU when the MCU receiver error flag received data available transmitter holding register empty or modem status interrupt is asserted INTO at RINGWAKE Used to notify the host of an incoming ring in order to come out of suspend mode LED3 0 o LED Drivers Designed to drive LEDs connected directly to VCC NC OVRI P3 0 Overcurrent Sense
21. xant MD211 Integrated V 90 K56flex Modem Device Sets with USB Interface RC56D USB Configuration Descriptor A configuration descriptor describes information about a specific device configuration see Table 4 The descriptor describes the number of interfaces provided by the configuration Table 4 Configuration Descriptors Offset Field Size Value Detaut Description oo bLength J1 Number o9 Size of this descriptor in bytes bDescriptorType CONFIGURATION 2 wTotalLength 2 Number 002E Total length of data returned for this configuration Includes the combined length of all descriptors configuration interface endpoint and class or vendor specific returned for this configuration 4 bNuminterfaces Li e or Number of interfaces supported by this configuration bConfiguration Value Number Value to use as an argument to Set Configuration to select this configuration 6 iConfiguration 1 Index o Index of string descriptor describing this configuration 7 bmAttributes 1 Bitmap AO Configuration characteristics D7 Bus Powered D6 Self Powered D5 Remote Wakeup D4 0 Reserved reset to 0 A device configuration that uses power from the bus and a local source sets both D7 and D6 The actual power source at runtime may be determined using the Get Status device request If a device configuration supports remote wakeup D5 is set to 1 MaxPower 1 mA C8 Maximum power consumption of USB device from the bus
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