RX Message Registers, 2. RX Message Routing

RX Message Registers

A 4-message-deep FIFO stores the incoming messages. Status flags indicate how many messages are stored. Additional flags determine from which acceptance filter the actual message is coming from.

Figure 5-2. RX Message Routing

uP Bus	0	1	2	3

	RxMessage	RxMessage	RxMessage	RxMessage
	RxMessage	RxMessage	RxMessage	RxMessage

To read received messages:

1.Wait for rx_msg interrupt.

2.MessageReadLoop:

MESSAGE FILTERS

CAN Module

CAN BUS

read message

acknowledge ‘ message read’ by writing a ‘ 1’ to MsgAv register read MsgAv; reading a ‘ 1’ means a new message is available IF MsgAv=1 THEN jump to MessageReadLoop

3.Acknowledge rx_msg interrupt by writing a ‘ 1’ to this register location.

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Lantronix DSTni-EX manual RX Message Registers, 2. RX Message Routing

Contents

DSTni-EX User Guide Section FivePage Technical Support Copyright & TrademarkLantronix Master Distributor Warranty 2 SPI Controller Contents1 About This User Guide 3 I2C Controller List of Tables 5 CAN Controllers Table 3-17. Clock Control Register List of Figures 1 About This User Guide Navigating Online Intended AudienceConventions Notes Notes are information requiring attention Organization SPI Background 2 SPI ControllerTheory of Operation DSTni SPI Controller SPI Controller Register Summary Table 2-1. SPI Controller Register Summary RESET SPI Controller Register DefinitionsSPIDATA Register Table 2-2. SPIDATA Register Phase Select CTL RegisterInterrupt Request Enable Wire-O Table 2-7. SPISTAT Register Definitions SPISTAT RegisterTable 2-6. SPISTAT Register Interrupt Request SelectO Signal SPISSEL RegisterTable 2-10. BCNT Bit Settings Table 2-8. SPISSEL Register Table 2-11. DVDCNTRLO Register DVDCNTRLO RegisterDVDCNTRHI Table 2-12. DVDCNTRLO Register Definitions Features 3 I2C Controller Figure 3-1. DSTni I2C Controller Block Diagram Block DiagramI2C Background Master Transmit Mode I2C ControllerOperating Modes I2C State Table 3-1. Master Transmit Status CodesCode Microprocessor Response Servicing the Interrupt Table 3-2. Codes After Servicing Interrupts Master Transmit All Bytes Transmit Completely Transmitting Each Data ByteTable 3-3. Status Codes After Each Data Byte Transmits Master Receive Mode Table 3-4. Master Receive Status Codes Table 3-5. Codes After Servicing Interrupt Master Receive Slave Transmit Mode Receiving Each Data ByteTable 3-6. Codes After Receiving Each Data Byte Slave Receive Mode Clock Synchronization Bus Clock ConsiderationsBus Clock Speed Bus Arbitration Resetting the I2C Controller Programmer’s ReferenceI2C Controller Register Summary Table 3-7. I 2C Controller Register Summary General Call Address Enable I2C Controller Register DefinitionsSlave Address Register Table 3-8. Slave Address Register Data Register Table 3-10. Data Register Table 3-13. Control Register Definitions Control RegisterTable 3-12. Control Register Extended Slave Address Status Register Table 3-14. Status Register Status Code Table 3-15. Status Register DefinitionsTable 3-16. Status Codes Table 3-18. Clock Control Register Definitions Clock Control RegisterTable 3-17. Clock Control Register Table 3-21. Software Reset Register Software Reset RegisterExtended Slave Address Register Table 3-22. Software Reset Register Definitions 4 USB Controller USB Core USB BackgroundUSB Interrupt Serial Interface Engine Microprocessor Interface USB Hardware/Software InterfaceDigital Phase Lock Loop Logic Buffer Descriptor Table Figure 4-1. Buffer Descriptor Table Rx vs. Tx as a Target Device or Host Table 4-2. 16-Bit USB Address Table 4-1. USB Data DirectionAddressing BDT Entries Table 4-3. 16-Bit USB Address Definitions Microprocessor Determines… Table 4-4. BDT Data Used by USB Controller and MicroprocessorUSB Controller Determines… Table 4-5. USB Buffer Descriptor Format DATA0/1 Transmit or Receive Table 4-6. USB Buffer Descriptor Format DefinitionsBD Owner USB Ownership USB Transaction Figure 4-2. USB Token Transaction Dedicated to host mode USB Register SummaryTable 4-7. USB Register Summary Table 4-8. Interrupt Status Register USB Register DefinitionsInterrupt Status Register Table 4-9. 16- Interrupt Status Register Definitions Error Condition Enable/Disable USBRST InterruptSleep Timer USB Reset Table 4-11. 16- Error Interrupt Status Register Definitions Error RegisterTable 4-10. Error Interrupt Status Register CRC16 Failure Error interrupt with two functionsData Field Received Not 8 Bits PID check field failed Table 4-12. Status Register Live USB Differential Receiver JSTATE SignalLive USB Single Ended Zero Signal Table 4-13. Status Register Definitions Resume Signaling USB Reset SignalHost Mode Enable valid for host mode only BDT PDD Reset Table 4-15. 16- Address Register Definitions Address RegisterTable 4-14. Address Register Table 4-17. Frame Number Register Definitions Frame Number RegistersTable 4-16. Frame Number Register Frame Number Token Register Table 4-19. Token Register Definitions Endpoint for Token CommandTable 4-18. Token Register Table 4-20. Valid PID Tokens Table 4-21. Endpoint Control Registers Endpoint Control RegistersEndpoint Enable Table 4-22. Endpoint Control Register Definitions Host Mode Operation Table 4-23. Endpoint Control Register Definitions Sample Host Mode Operations Figure 3. Enable Host Mode and Configure a Target Device Figure 4. Full-Speed Bulk Data Transfers to a Target Device USB Pull-up/Pull-down Resistors Figure 4-5. Pull-up/Pull-down USB HOST Mode Enable USB Interface SignalsUSB Output Enable Clock CLK 5 CAN Controllers Data Exchanges and Communication Arbitration and Error CheckingCANBUS Background CANBUS Speed and Length Table 5-1. Bit Rates for Different Cable Lengths Hex Offset CAN Register SummariesRegister Summary Register Hex Offset Detailed CAN Register Map Table 5-4. Detailed CAN Register Map Acceptance Filter Enable Register Hex Offset Register Figure 5-1. TX Message Routing CAN Register DefinitionsTX Message Registers Sending a Message Table 5-6. TxMessage0ID12 Tx Message RegistersTable 5-5. TxMessage0ID28 Table 5-7. TxMessage0Data Message Identifier for Both Standard and Extended Messages Table 5-12. TxMessage0Ctrl FlagsTable 5-13. TxMessage0 Register Definitions Message Data RX Message Registers Figure 5-2. RX Message Routing Table 5-15. Rx Message ID28 Register Definitions Rx Message RegistersTable 5-14. RxMessageID28 Table 5-16. RxMessageID12 Table 5-22. Rx Message Data Table 5-20. Rx Message DataTable 5-21. Rx Message Data 39 Register Definitions Table 5-23. Rx Message Data 23 Register Definitions Table 5-28. Rx Message Msg Flags Table 5-26. RxMessage RTRTable 5-27. Rx Message RTR Register Definitions Table 5-29. Rx Message Msg Flags Register Definitions Table 5-31. Tx\Rx Error Count Register Definitions Error Count and Status RegistersTable 5-30. Tx/Rx Error Count Table 5-32. Error Status rxlevel10 Table 5-34. Tx/Rx Message Level RegisterTable 5-35. Tx/Rx Message Level Register Definitions txlevel10 CRC Error Interrupt FlagsNote The reset value of this register’s bits is indeterminate Format Error Table 5-39. Interrupt Enable Register Definitions Interrupt Enable RegistersTable 5-38. Interrupt Enable Registers Bus Off State − int2n group error interrupts Table 5-41. Interrupt Enable Register Definitions CAN Operating ModeTable 5-40. Interrupt Enable Registers Overload Condition − int3n group diagnostic interrupts Figure 5-3. CAN Operating Mode CAN Configuration RegistersConfiguration Bit Rate Table 5-42. Bit Rate Divisor Register Overwrite Last Message Table 5-44. Configuration RegisterTable 5-45. Configuration Register Definitions Cfgsjw tseg2 + Bit Timetseg1 + time quanta TQ Table 5-47. Acceptance Filter Enable Register Definitions Acceptance Filter and Acceptance Code MaskTable 5-46. Acceptance Filter Enable Register Table 5-48. Acceptance Mask 0 Register Table 5-52. Acceptance Mask Register Data Table 5-50. Acceptance Mask Register IDTable 5-51. Acceptance Mask Register ID12 Definitions D5556 Table 5-56. Acceptance Mask Register ID12 Table 5-54. Acceptance Code RegisterTable 5-55. Acceptance Code Register Definitions Table 5-57. Acceptance Mask Register ID12 Definitions Table 5-60. Arbitration Lost Capture Register CANbus AnalysisArbitration Lost Capture Register Table 5-61. Arbitration Lost Capture Register Definitions Table 5-63. Error Capture Register Definitions Error Capture RegisterTable 5-62. Error Capture Register Errorcode Table 5-64. Frame Reference Register Table 5-65. Error Capture Register DefinitionsFrame Reference Register Stuff Bit Inserted Figure 5-6. CAN Connector CAN Bus InterfaceInterface Connections Figure 5-5. CAN Bus Interface GNDCAN Figure 5-7. Power for CAN+5CAN +24V Figure 5-8. CAN Transceiver and Isolation Circuits 0.01uf