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Intel 8XC196NT 87C196CB SUPPLEMENT, 14. CAN Message Object x Control 0 CANMSGxCON0 Register

Models: 8XC196NT 87C196CB

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Program the CAN message object x control 0 (CAN_MSGxCON0) register to indicate whether the message object is ready to transmit and to control whether a successful transmission or reception generates an interrupt. The least-significant bit-pair indicates whether an interrupt is pending.

87C196CB SUPPLEMENT

CAN_MSGxCON0	Address:	1Ex0H (x = 1–F)
x = 1–15 (87C196CB)	Reset State:	Unchanged

Program the CAN message object x control 0 (CAN_MSGxCON0) register to indicate whether the message object is ready to transmit and to control whether a successful transmission or reception generates an interrupt. The least-significant bit-pair indicates whether an interrupt is pending.

This register consists of four bit-pairs — the most-significant bit of each pair is in true form and the least-significant bit is in complement form. This format allows software to set or clear any bit with a single write operation, without affecting the remaining bits.

87C196CB

7

MSGVAL	MSGVAL	TXIE	TXIE

0

RXIE	RXIE	INT_PND	INT_PND

Bit	Bit			Function
Number	Mnemonic			Function
Number	Mnemonic

7:6	MSGVAL	Message Object Valid
		Set this bit-pair to indicate that a message object is valid (configured and
		ready for transmission or reception).
		bit 7	bit 6
		0	1	not ready
		1	0	message object is valid
		The CAN peripheral will access a message object only if this bit-pair
		indicates that the message is valid. If multiple message objects have the
		same identifier, only one can be valid at any given time.
		During initialization, software should clear this bit for any unused message
		objects. Software can clear this bit if a message is no longer needed or if
		you need to change a message object’s contents or identifier.

5:4	TXIE	Transmit Interrupt Enable
		Receive message objects do not use this bit-pair.
		For transmit message objects, set this bit-pair to enable the CAN
		peripheral to initiate a transmit (TX) interrupt after a successful trans-
		mission. You must also set the interrupt enable bit (CAN_CON.1) to enable
		the interrupt.
		bit 5	bit 4
		0	1	no interrupt
		1	0	generate an interrupt

Figure 7-14. CAN Message Object x Control 0 (CAN_MSGxCON0) Register

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Image 85

Intel 8XC196NT user manual 87C196CB SUPPLEMENT, 14. CAN Message Object x Control 0 CANMSGxCON0 Register

Contents

87C196CB Supplement to 8XC196NT User’s Manual August 87C196CB Supplement to 8XC196NT User’s ManualOrder Number Copyright Intel Corporation, 1998 CHAPTER CONTENTSGUIDE TO THIS MANUAL CHAPTER87C196CB SUPPLEMENT SIGNAL DESCRIPTIONSCHAPTER SPECIAL OPERATING MODESCONTENTS FIGURESInternal Clock Phases Effect of Clock Mode on CLKOUT Frequency8XC196CB SUPPLEMENT FIGURESPage 87C196CB 100-pin QFP PackageCONTENTS TABLESPage Page Guide to This Manual Page CHAPTER GUIDE TO THIS MANUAL 1.1 MANUAL CONTENTSAppendix A - Signal Descriptions 1.2 RELATED DOCUMENTSChapter 9 - Interfacing with External Memory Architectural Overview Page CHAPTER ARCHITECTURAL OVERVIEW 2.1 DEVICE FEATURES2.3 INTERNAL TIMING 2.2 BLOCK DIAGRAMPage 12 MHz 8 MHz16 MHz 20 MHzARCHITECTURAL OVERVIEW Figure 2-4. Effect of Clock Mode on CLKOUT FrequencyFrequency Input Frequency toPage Memory Partitions Page 3.1 MEMORY MAP, SPECIAL-FUNCTION REGISTERS, AND WINDOWING CHAPTER MEMORY PARTITIONSAddress 87C196CB SUPPLEMENT Table 3-2. 87C196CB Memory MapMEMORY PARTITIONS Table 3-3. 87C196CB Peripheral SFRs Timer 1, Timer 2, and EPA SFRsPorts 0, 1, 2, and 6 SFRs SIO and SSIO SFRs1EDCH 87C196CB SUPPLEMENT Table 3-4. CAN Peripheral SFRs1ECCH Message MEMORY PARTITIONS Table 3-4. CAN Peripheral SFRs Continued32-byte Window 87C196CB SUPPLEMENT Table 3-5. Selecting a Window of Peripheral SFRs64-byte Window 128-byte WindowTable 3-6. Selecting a Window of the Upper Register File MEMORY PARTITIONSRegister RAM Locations87C196CB SUPPLEMENT Table 3-7. Selecting a Window of Upper Register RAM MEMORY PARTITIONS0DE0-0DFFH 87C196CB SUPPLEMENT Table 3-8. Windows Table 3-8. Windows Continued MEMORY PARTITIONSUpper Register File 87C196CB SUPPLEMENT Table 3-9. WSR Settings and Direct Addresses for Windowable SFRsMEMORY PARTITIONS 87C196CB SUPPLEMENT MEMORY PARTITIONS 87C196CB SUPPLEMENT MEMORY PARTITIONS 87C196CB SUPPLEMENT 32-byte Windows MEMORY PARTITIONS64-byte Windows 128-byte Windows32-byte Windows Standard and PTS Interrupts Page 4.1 INTERRUPT SOURCES, VECTORS, AND PRIORITIES CHAPTER STANDARD AND PTS INTERRUPTSFigure 4-1. Interrupt Mask 1 INTMASK1 Register 87C196CB SUPPLEMENTFigure 4-2. interrupt Pending 1 INTPEND1 Register Standard VectorI/O Ports Page 5.1 PORT 0 AND EPORT CHAPTER I/O PORTS87C196CB SUPPLEMENT Figure 5-3. Extended Port Mode EPMODE RegisterFigure 5-2. Extended Port I/O Direction EPDIR Register EPDIRFigure 5-4. Extended Port Input EPPIN Register I/O PORTSFigure 5-5. Extended Port Data Output EPREG Register EPPINPage Analog-to-digital A/D Converter Page 6.1 ADDITIONAL A/D INPUT CHANNELS CHAPTER 6 ANALOG-TO-DIGITAL A/D CONVERTERADCOMMAND Figure 6-1. A/D Command ADCOMMAND Register87C196CB SUPPLEMENT FunctionFigure 6-2. A/D Result ADRESULT Register - Read Format ANALOG-TO-DIGITAL A/D CONVERTERADRESULT Read FunctionPage CAN Serial Communications Controller Page 7.1 CAN FUNCTIONAL OVERVIEW CHAPTER 7 CAN SERIAL COMMUNICATIONS CONTROLLERPage Table 7-1. CAN Controller Signals 7.2 CAN CONTROLLER SIGNALS AND REGISTERSCAN SERIAL COMMUNICATIONS CONTROLLER Table 7-2. Control and Status Registers87C196CB SUPPLEMENT Table 7-2. Control and Status Registers Continued 7.3 CAN CONTROLLER OPERATION7.3.2 Message Objects 7.3.1 Address Map87C196CB SUPPLEMENT Table 7-4. Message Object Structure Contents7.3.2.1 Receive and Transmit Priorities 7.3.2.2 Message Acceptance Filtering7.3.3 Message Frames Table 7-7. Extended Message Frame 87C196CB SUPPLEMENT Table 7-6. Standard Message Frame7.3.4 Error Detection and Management Logic Symbol 7.3.5 Bit TimingDefinition Figure 7-5. A Bit Time as Implemented in the CAN Controller CAN SERIAL COMMUNICATIONS CONTROLLERTable 7-9. CAN Controller Bit Time Segments t SYNCTable 7-10 defines the bit timing relationships of the CAN controller where87C196CB SUPPLEMENT 7.3.5.1 Bit Timing Equations Table 7-10. Bit Timing Relationships7.4.1 Programming the CAN Control CANCON Register 7.4 CONFIGURING THE CAN CONTROLLER87C196CB SUPPLEMENT This bit globally enables and disables interrupts error, status-change, andFigure 7-6. CAN Control CANCON Register Continued Unchanged 7.4.2 Programming the Bit Timing 0 CANBTIME0 Register87C196CB SUPPLEMENT 7.4.3 Programming the Bit Timing 1 CANBTIME1 RegisterFigure 7-8. CAN Bit Timing 1 CANBTIME1 Register TSEG2Bit Time 7.4.4 Programming a Message Acceptance FilterRequirement CommentsFigure 7-9. CAN Standard Global Mask CANSGMSK Register 87C196CB SUPPLEMENTCANSGMSK 87C196CBFigure 7-10. CAN Extended Global Mask CANEGMSK Register CAN SERIAL COMMUNICATIONS CONTROLLERCANEGMSK 87C196CB87C196CB SUPPLEMENT 7.5 CONFIGURING MESSAGE OBJECTSFigure 7-11. CAN Message 15 Mask CANMSK15 Register 7.5.1 Specifying a Message Object’s Configuration 87C196CB SUPPLEMENT 7.5.2 Programming the Message Object IdentifierFigure 7-13. CAN Message Object x Identifier CANMSGxID0-3 Register 7.5.4 Programming the Message Object Data 7.5.3 Programming the Message Object Control RegistersAccess Type Figure 7-14. CAN Message Object x Control 0 CANMSGxCON0 Register 87C196CB SUPPLEMENTProgram the CAN message object x control 0 CANMSGxCON0 register to indicate whether the message object is ready to transmit and to control whether a successful transmission or reception generates an interrupt. The least-significant bit-pair indicates whether an interrupt is pending CAN SERIAL COMMUNICATIONS CONTROLLER Figure 7-15. CAN Message Object x Control 1 CANMSGxCON1 Register 87C196CB SUPPLEMENTCAN SERIAL COMMUNICATIONS CONTROLLER Figure 7-16. CAN Message Object Data CANMSGxDATA0-7 Registers 87C196CB SUPPLEMENTFunction 7.6 ENABLING THE CAN INTERRUPTS Figure 7-17. CAN Control CANCON Register Continued 87C196CB SUPPLEMENTCANCON Continued 87C196CBWhen the SIE bit in the CAN control register is set, the CAN controller generates a successful reception RXOK interrupt request each time it receives a valid message, even if no message ob- ject accepts it. If you set both the SIE bit Figure 7-17 and an individual message object’s RXIE bit Figure 7-18, the CAN controller generates two interrupt requests each time a message object receives a message. The status change interrupt is useful during development to detect bus errors caused by noise or other hardware problems. However, you should disable this interrupt during normal operation in most applications. If the status change interrupt is enabled, each status change generates an interrupt request, placing an unnecessary burden on the CPU. To prevent re- dundant interrupt requests, enable the error interrupt sources with the EIE bit and enable the re- ceive and transmit interrupts in the individual message objects 7.7 DETERMINING THE CAN CONTROLLER’S INTERRUPT STATUS Figure 7-20. CAN Status CANSTAT Register CAN SERIAL COMMUNICATIONS CONTROLLERFigure 7-21. CAN Message Object x Control 0 CANMSGxCON0 Register 87C196CB SUPPLEMENTRegister Mnemonic 7.8 FLOW DIAGRAMS87C196CB SUPPLEMENT Process message contentsFigure 7-22. Receiving a Message for Message Objects 1-14 - CPU Flow A2594-01Figure 7-23. Receiving a Message for Message Object 15 - CPU Flow CAN SERIAL COMMUNICATIONS CONTROLLERRestart Process Figure 7-24. Receiving a Message - CAN Controller Flow 87C196CB SUPPLEMENTReceived frame with same identifer as thisUpdate Power UpCAN SERIAL COMMUNICATIONS CONTROLLER Figure 7-25. Transmitting a Message - CPU FlowFigure 7-26. Transmitting a Message - CAN Controller Flow 87C196CB SUPPLEMENTReceived remote frame with same identifer as7.9 DESIGN CONSIDERATIONS 7.9.1 Hardware Reset7.9.2 Software Initialization 7.9.3 Bus-off StateThe CAN controller synchronizes itself to the CAN bus by waiting for 128 bus idle states 128 occurrences of 11 consecutive recessive bits before participating in bus activities. During this sequence, the CAN controller writes a bit 0 error code to the LEC20 bits of the status register each time it receives a recessive bit. Software can check the status register to determine whether the CAN bus is stuck in a dominant state. Once the CAN controller is resynchronized with the CAN bus, it clears the BUSOFF bit and starts transferring messages again Special Operating Modes Page 8.1 CLOCK CIRCUITRY CHAPTER SPECIAL OPERATING MODESFigure 8-1. Clock Circuitry Page Interfacing with External Memory Page CHAPTER 9 INTERFACING WITH EXTERNAL MEMORY 9.1 ADDRESS PINS9.2 BUS TIMING MODES Figure 9-1. Modes 0 and 3 Timings 87C196CB SUPPLEMENTT RLDV = 1t T AVDV = 3tno direct access † Figure 9-2. Chip Configuration 1 CCR1 Register= always enabled INTERFACING WITH EXTERNAL MEMORY87C196CB SUPPLEMENT Figure 9-2. Chip Configuration 1 CCR1 Register ContinuedCCR1 Continued FunctionProgramming the Nonvolatile Memory Page CHAPTER 10 PROGRAMMING THE NONVOLATILE MEMORY 10.2 MEMORY MAP FOR SLAVE PROGRAMMING MODE10.1 SIGNATURE WORD AND PROGRAMMING VOLTAGES 87C196CB SUPPLEMENT Table 10-2. Slave Programming Mode Memory Map 10.3 MEMORY MAP AND CIRCUIT FOR AUTO PROGRAMMINGTable 10-3. Auto Programming Memory Map PROGRAMMING THE NONVOLATILE MEMORY 10.4 MEMORY MAP FOR SERIAL PORT PROGRAMMINGFigure 10-1. Auto Programming Circuit 74HC1410.4.2 Selecting Bank 1 FF8000-FFFFFFH 10.4.1 Selecting Bank 0 FF2000-FF7FFFHSerial Port Programming Mode Signal Descriptions Page A.1 FUNCTIONAL GROUPINGS OF SIGNALS APPENDIX A SIGNAL DESCRIPTIONSFigure A-1. 87C196CB 84-pin PLCC Package 87C196CB Supplementxx87C196CB View of component asSIGNAL DESCRIPTIONS A.2 SIGNAL DESCRIPTIONSFigure A-2. 87C196CB 100-pin QFP Package xx87C196CB87C196CB Supplement Table A-3. Signal DescriptionsTable A-2. Description of Columns of Table A-3 Table A-3. Signal Descriptions Continued SIGNAL DESCRIPTIONSread or write. AINC# is sampled after each location is programmed or dumped 87C196CB Supplement Table A-3. Signal Descriptions ContinuedTable A-3. Signal Descriptions Continued SIGNAL DESCRIPTIONS87C196CB Supplement Table A-3. Signal Descriptions ContinuedTable A-3. Signal Descriptions Continued SIGNAL DESCRIPTIONS87C196CB Supplement Table A-3. Signal Descriptions ContinuedA-10 Table A-3. Signal Descriptions Continued SIGNAL DESCRIPTIONSA-11 87C196CB Supplement Table A-3. Signal Descriptions ContinuedA-12 Table A-3. Signal Descriptions Continued SIGNAL DESCRIPTIONSA-13 Table A-3. Signal Descriptions Continued A.3 DEFAULT CONDITIONSTable A-4. Definition of Status Symbols 87C196CB SupplementTable A-5. 87C196CB Pin Status Continued SIGNAL DESCRIPTIONSA-15 Page Glossary Page GLOSSARY two adjacent code transitions on the A/D converter transfer function of an A/D converterchannel-to-channel matching error characteristicSee off-isolation earity errorsconversion result. Differential nonlinearity is a code widthlinearity errors. Quantizing error is the only error The characteristic of an ideal A/D converter. An idealare to be serviced by interrupt service routines that starting address of an interrupt service routineSee differential nonlinearity and nonlinearity See interrupt service routinelinearity errors serviced by interrupt service routines that you terminal-based characteristic from the correOTPROM. Consult the Automotive Products or Embedded Microcontrollers databook to determineSee PTS control block directly to the interrupt service routine whenprioritized interrupt ideal A/D converter transitions from different actual characteristics takenquantizing error repeatability errorthe A/D converter Successive approximation register. A component ofsample delay scaled to remove zero-offset error and full-scale service routinecharacteristic of the A/D converter interrupt controller for processing by an interrupterror, differential nonlinearity, and nonlinearity process quantizing error, zero-offset error, full-scaleisolation, and VCC rejection errors characteristicPage Index Page INDEX Index-2 87C196CB SUPPLEMENT