Lantronix DSTni-EX CANBUS Speed and Length, Features, 1. Bit Rates for Different Cable Lengths

Page 65

CANBUS Speed and Length

Table 7-1 shows the relationship between the bit rate and cable length.

Table 5-1. Bit Rates for Different Cable Lengths

Bit Rate	Cable Length
10 KB/s	6.7 km
20 KB/s	3.3 km
50 KB/s	1.3 km
125 KB/s	530 m
250 KB/s	270 m
500 KB/s	130 m
1 MB/s	40 m

Features

Three programmable acceptance filters

−Message filter covers: ID, IDE, RTR, 16 DATA bits

−Each filter has its own enable flag

Transmit Path

−Three Tx message holding registers with internal priority arbiter

−Message abort command

Receive FIFO

−Four message deep receive FIFO

−FIFO status indicator

Bus coupler

−Intel style interface module

−Full synchronous zero wait-states interface

−Status and configuration interface

Programmable Interrupt Controller

Listen only mode

CANbus analysis functions

−Arbitration lost capture

−Error event capture

−Actual frame reference pointer

Programmable CANbus physical layer interface

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Contents Section Five DSTni-EX User GuidePage Lantronix Copyright & TrademarkTechnical Support Master DistributorWarranty 1 About This User Guide Contents2 SPI Controller 3 I2C Controller5 CAN Controllers List of TablesTable 3-17. Clock Control Register List of Figures 1 About This User Guide Conventions Intended AudienceNavigating Online Notes Notes are information requiring attentionOrganization Theory of Operation 2 SPI ControllerSPI Background DSTni SPI ControllerTable 2-1. SPI Controller Register Summary SPI Controller Register SummarySPIDATA Register SPI Controller Register DefinitionsRESET Table 2-2. SPIDATA RegisterInterrupt Request Enable CTL RegisterPhase Select Wire-OTable 2-6. SPISTAT Register SPISTAT RegisterTable 2-7. SPISTAT Register Definitions Interrupt RequestTable 2-10. BCNT Bit Settings SPISSEL RegisterSelectO Signal Table 2-8. SPISSEL RegisterDVDCNTRHI DVDCNTRLO RegisterTable 2-11. DVDCNTRLO Register Table 2-12. DVDCNTRLO Register Definitions3 I2C Controller FeaturesFigure 3-1. DSTni I2C Controller Block Diagram Block DiagramI2C Background Master Transmit Mode I2C ControllerOperating Modes Code Table 3-1. Master Transmit Status CodesI2C State Microprocessor ResponseTable 3-2. Codes After Servicing Interrupts Master Transmit Servicing the InterruptTable 3-3. Status Codes After Each Data Byte Transmits Transmitting Each Data ByteAll Bytes Transmit Completely Master Receive ModeTable 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 Bus Clock Speed Bus Clock ConsiderationsClock Synchronization Bus ArbitrationI2C Controller Register Summary Programmer’s ReferenceResetting the I2C Controller Table 3-7. I 2C Controller Register SummarySlave Address Register I2C Controller Register DefinitionsGeneral Call Address Enable Table 3-8. Slave Address RegisterTable 3-10. Data Register Data RegisterTable 3-12. Control Register Control RegisterTable 3-13. Control Register Definitions Extended Slave AddressTable 3-14. Status Register Status RegisterStatus 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 Extended Slave Address Register Software Reset RegisterTable 3-21. Software Reset Register Table 3-22. Software Reset Register Definitions4 USB Controller USB Interrupt USB BackgroundUSB Core Serial Interface EngineDigital Phase Lock Loop Logic USB Hardware/Software InterfaceMicroprocessor Interface Buffer Descriptor TableRx vs. Tx as a Target Device or Host Figure 4-1. Buffer Descriptor TableAddressing BDT Entries Table 4-1. USB Data DirectionTable 4-2. 16-Bit USB Address Table 4-3. 16-Bit USB Address DefinitionsUSB Controller Determines… Table 4-4. BDT Data Used by USB Controller and MicroprocessorMicroprocessor Determines… Table 4-5. USB Buffer Descriptor FormatBD Owner Table 4-6. USB Buffer Descriptor Format DefinitionsDATA0/1 Transmit or Receive USB OwnershipFigure 4-2. USB Token Transaction USB TransactionDedicated to host mode USB Register SummaryTable 4-7. USB Register Summary Interrupt Status Register USB Register DefinitionsTable 4-8. Interrupt Status Register Table 4-9. 16- Interrupt Status Register DefinitionsSleep Timer Enable/Disable USBRST InterruptError Condition USB ResetTable 4-11. 16- Error Interrupt Status Register Definitions Error RegisterTable 4-10. Error Interrupt Status Register Data Field Received Not 8 Bits Error interrupt with two functionsCRC16 Failure PID check field failedLive USB Single Ended Zero Signal Live USB Differential Receiver JSTATE SignalTable 4-12. Status Register Table 4-13. Status Register DefinitionsHost Mode Enable valid for host mode only USB Reset SignalResume Signaling BDT PDD ResetTable 4-15. 16- Address Register Definitions Address RegisterTable 4-14. Address Register Table 4-16. Frame Number Register Frame Number RegistersTable 4-17. Frame Number Register Definitions Frame NumberToken Register Table 4-18. Token Register Endpoint for Token CommandTable 4-19. Token Register Definitions Table 4-20. Valid PID TokensEndpoint Enable Endpoint Control RegistersTable 4-21. Endpoint Control Registers Table 4-22. Endpoint Control Register DefinitionsTable 4-23. Endpoint Control Register Definitions Host Mode OperationFigure 3. Enable Host Mode and Configure a Target Device Sample Host Mode OperationsFigure 4. Full-Speed Bulk Data Transfers to a Target Device Figure 4-5. Pull-up/Pull-down USB USB Pull-up/Pull-down ResistorsUSB Output Enable USB Interface SignalsHOST Mode Enable Clock CLK5 CAN Controllers Data Exchanges and Communication Arbitration and Error CheckingCANBUS Background Table 5-1. Bit Rates for Different Cable Lengths CANBUS Speed and LengthRegister Summary CAN Register SummariesHex Offset RegisterRegister Table 5-4. Detailed CAN Register Map Detailed CAN Register MapHex Offset Acceptance Filter Enable RegisterRegister TX Message Registers CAN Register DefinitionsFigure 5-1. TX Message Routing Sending a MessageTable 5-5. TxMessage0ID28 Tx Message RegistersTable 5-6. TxMessage0ID12 Table 5-7. TxMessage0DataTable 5-13. TxMessage0 Register Definitions Table 5-12. TxMessage0Ctrl FlagsMessage Identifier for Both Standard and Extended Messages Message DataFigure 5-2. RX Message Routing RX Message RegistersTable 5-14. RxMessageID28 Rx Message RegistersTable 5-15. Rx Message ID28 Register Definitions Table 5-16. RxMessageID12Table 5-21. Rx Message Data 39 Register Definitions Table 5-20. Rx Message DataTable 5-22. Rx Message Data Table 5-23. Rx Message Data 23 Register DefinitionsTable 5-27. Rx Message RTR Register Definitions Table 5-26. RxMessage RTRTable 5-28. Rx Message Msg Flags Table 5-29. Rx Message Msg Flags Register DefinitionsTable 5-30. Tx/Rx Error Count Error Count and Status RegistersTable 5-31. Tx\Rx Error Count Register Definitions Table 5-32. Error StatusTable 5-35. Tx/Rx Message Level Register Definitions Table 5-34. Tx/Rx Message Level Registerrxlevel10 txlevel10Note The reset value of this register’s bits is indeterminate Interrupt FlagsCRC Error Format ErrorTable 5-38. Interrupt Enable Registers Interrupt Enable RegistersTable 5-39. Interrupt Enable Register Definitions Bus Off State − int2n group error interruptsTable 5-40. Interrupt Enable Registers CAN Operating ModeTable 5-41. Interrupt Enable Register Definitions Overload Condition − int3n group diagnostic interruptsConfiguration Bit Rate CAN Configuration RegistersFigure 5-3. CAN Operating Mode Table 5-42. Bit Rate Divisor RegisterTable 5-45. Configuration Register Definitions Table 5-44. Configuration RegisterOverwrite Last Message Cfgsjwtseg1 + Bit Timetseg2 + time quanta TQTable 5-46. Acceptance Filter Enable Register Acceptance Filter and Acceptance Code MaskTable 5-47. Acceptance Filter Enable Register Definitions Table 5-48. Acceptance Mask 0 RegisterTable 5-51. Acceptance Mask Register ID12 Definitions Table 5-50. Acceptance Mask Register IDTable 5-52. Acceptance Mask Register Data D5556Table 5-55. Acceptance Code Register Definitions Table 5-54. Acceptance Code RegisterTable 5-56. Acceptance Mask Register ID12 Table 5-57. Acceptance Mask Register ID12 DefinitionsArbitration Lost Capture Register CANbus AnalysisTable 5-60. Arbitration Lost Capture Register Table 5-61. Arbitration Lost Capture Register DefinitionsTable 5-62. Error Capture Register Error Capture RegisterTable 5-63. Error Capture Register Definitions ErrorcodeFrame Reference Register Table 5-65. Error Capture Register DefinitionsTable 5-64. Frame Reference Register Stuff Bit InsertedInterface Connections CAN Bus InterfaceFigure 5-6. CAN Connector Figure 5-5. CAN Bus Interface+5CAN Figure 5-7. Power for CANGNDCAN +24V0.01uf Figure 5-8. CAN Transceiver and Isolation Circuits