Lantronix DSTni-EX manual Slave Receive Mode

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−The IFLG is set and the Status register contains B8h.

−After the last transmission byte loads in the Data register, clear AAK when IFLG clears.

−After the last byte is transmitted, the IFLG is set and the Status register contains C8h.

−The I2C controller returns to the idle state and the AAK bit must be set to 1 before slave mode can be entered again.

If the I2C controller does not receive an acknowledge:

−The IFLG is set.

−The Status register contains C0h.

−The I2C controller returns to the idle state.

4. If the I2C detects a STOP condition after an acknowledge bit, it returns to the idle state.

Slave Receive Mode

In slave receive mode, a number of data bytes are received from a master transmitter.

The I2C controller enters slave receive mode when it receives its own slave address and write bit (least-significant bit = 0) after a START condition. The I2C controller then transmits an acknowledge bit and sets the IFLG bit in the Control register. The Status register status code is 60h.

The I2C controller also enters slave receive mode when it receives the general call address 00h (if the GCE bit in the Slave Address register is set). The status code is 70h.

Note: If the I2C controller has an extended slave address (signified by F0h - F7h in the Slave Address register), it transmits an acknowledge after receiving the first address byte, but does not generate an interrupt; the IFLG is not set and the status does not change. Only after receiving the second address byte does the I2C controller generate an interrupt and set the IFLG bit and the status code as described above.

The I2C controller also enters slave transmit mode directly from a master mode if arbitration is lost during address transmission, and both the slave address and write bit (or general call address if bit GCE in the Slave Address register is set to one) are received. The status code in the Status register is 68h if the slave address is received or 78h if the general call address is received. The IFLG bit must clear to 0 to allow the data transfer to continue.

If the AAK bit in the Control register is set to 1:

1.Receiving each byte transmits an acknowledge bit (LOW level on SDA) and sets the IFLG bit.

2.The Status register contains status code 80h (or 90h if slave receive mode was entered with the general call address).

3.The received data byte can be read from the Data register and the IFLG bit must clear to allow the transfer to continue.

4.When the STOP condition or repeated START condition is detected after the acknowledge bit, the IFLG bit is set and the Status register contains status code A0h.

If the AAK bit clears to zero during a transfer, the I2C controller transfers a not acknowledge bit (high level on SDA) after the next byte is received and sets the IFLG bit. The Status register contains status code 88h (or 98h if slave receive mode was entered with the general call address). When the IFLG bit clears to zero, the I2C controller returns to the idle state.

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Contents DSTni-EX User Guide Section FivePage Copyright & Trademark LantronixTechnical Support Master DistributorWarranty Contents 1 About This User Guide2 SPI Controller 3 I2C ControllerList of Tables 5 CAN ControllersTable 3-17. Clock Control Register List of Figures 1 About This User Guide Intended Audience ConventionsNavigating Online Notes Notes are information requiring attentionOrganization 2 SPI Controller Theory of OperationSPI Background DSTni SPI ControllerSPI Controller Register Summary Table 2-1. SPI Controller Register SummarySPI Controller Register Definitions SPIDATA RegisterRESET Table 2-2. SPIDATA RegisterCTL Register Interrupt Request EnablePhase Select Wire-OSPISTAT Register Table 2-6. SPISTAT RegisterTable 2-7. SPISTAT Register Definitions Interrupt RequestSPISSEL Register Table 2-10. BCNT Bit SettingsSelectO Signal Table 2-8. SPISSEL RegisterDVDCNTRLO Register DVDCNTRHITable 2-11. DVDCNTRLO Register Table 2-12. DVDCNTRLO Register DefinitionsFeatures 3 I2C ControllerI2C Background Block DiagramFigure 3-1. DSTni I2C Controller Block Diagram Operating Modes I2C ControllerMaster Transmit Mode Table 3-1. Master Transmit Status Codes CodeI2C State Microprocessor ResponseServicing the Interrupt Table 3-2. Codes After Servicing Interrupts Master TransmitTransmitting Each Data Byte Table 3-3. Status Codes After Each Data Byte TransmitsAll Bytes Transmit Completely Master Receive Mode Table 3-4. Master Receive Status Codes Table 3-5. Codes After Servicing Interrupt Master Receive Table 3-6. Codes After Receiving Each Data Byte Receiving Each Data ByteSlave Transmit Mode Slave Receive Mode Bus Clock Considerations Bus Clock SpeedClock Synchronization Bus ArbitrationProgrammer’s Reference I2C Controller Register SummaryResetting the I2C Controller Table 3-7. I 2C Controller Register SummaryI2C Controller Register Definitions Slave Address RegisterGeneral Call Address Enable Table 3-8. Slave Address RegisterData Register Table 3-10. Data RegisterControl Register Table 3-12. Control RegisterTable 3-13. Control Register Definitions Extended Slave AddressStatus Register Table 3-14. Status RegisterTable 3-16. Status Codes Table 3-15. Status Register DefinitionsStatus Code Table 3-17. Clock Control Register Clock Control RegisterTable 3-18. Clock Control Register Definitions Software Reset Register Extended Slave Address RegisterTable 3-21. Software Reset Register Table 3-22. Software Reset Register Definitions4 USB Controller USB Background USB InterruptUSB Core Serial Interface EngineUSB Hardware/Software Interface Digital Phase Lock Loop LogicMicroprocessor Interface Buffer Descriptor TableFigure 4-1. Buffer Descriptor Table Rx vs. Tx as a Target Device or HostTable 4-1. USB Data Direction Addressing BDT EntriesTable 4-2. 16-Bit USB Address Table 4-3. 16-Bit USB Address DefinitionsTable 4-4. BDT Data Used by USB Controller and Microprocessor USB Controller Determines…Microprocessor Determines… Table 4-5. USB Buffer Descriptor FormatTable 4-6. USB Buffer Descriptor Format Definitions BD OwnerDATA0/1 Transmit or Receive USB OwnershipUSB Transaction Figure 4-2. USB Token TransactionTable 4-7. USB Register Summary USB Register SummaryDedicated to host mode USB Register Definitions Interrupt Status RegisterTable 4-8. Interrupt Status Register Table 4-9. 16- Interrupt Status Register DefinitionsEnable/Disable USBRST Interrupt Sleep TimerError Condition USB ResetTable 4-10. Error Interrupt Status Register Error RegisterTable 4-11. 16- Error Interrupt Status Register Definitions Error interrupt with two functions Data Field Received Not 8 BitsCRC16 Failure PID check field failedLive USB Differential Receiver JSTATE Signal Live USB Single Ended Zero SignalTable 4-12. Status Register Table 4-13. Status Register DefinitionsUSB Reset Signal Host Mode Enable valid for host mode onlyResume Signaling BDT PDD ResetTable 4-14. Address Register Address RegisterTable 4-15. 16- Address Register Definitions Frame Number Registers Table 4-16. Frame Number RegisterTable 4-17. Frame Number Register Definitions Frame NumberToken Register Endpoint for Token Command Table 4-18. Token RegisterTable 4-19. Token Register Definitions Table 4-20. Valid PID TokensEndpoint Control Registers Endpoint EnableTable 4-21. Endpoint Control Registers Table 4-22. Endpoint Control Register DefinitionsHost Mode Operation Table 4-23. Endpoint Control Register DefinitionsSample Host Mode Operations Figure 3. Enable Host Mode and Configure a Target DeviceFigure 4. Full-Speed Bulk Data Transfers to a Target Device USB Pull-up/Pull-down Resistors Figure 4-5. Pull-up/Pull-down USBUSB Interface Signals USB Output EnableHOST Mode Enable Clock CLK5 CAN Controllers CANBUS Background Arbitration and Error CheckingData Exchanges and Communication CANBUS Speed and Length Table 5-1. Bit Rates for Different Cable LengthsCAN Register Summaries Register SummaryHex Offset RegisterHex Offset Detailed CAN Register Map Table 5-4. Detailed CAN Register MapAcceptance Filter Enable Register Hex OffsetRegister CAN Register Definitions TX Message RegistersFigure 5-1. TX Message Routing Sending a MessageTx Message Registers Table 5-5. TxMessage0ID28Table 5-6. TxMessage0ID12 Table 5-7. TxMessage0DataTable 5-12. TxMessage0Ctrl Flags Table 5-13. TxMessage0 Register DefinitionsMessage Identifier for Both Standard and Extended Messages Message DataRX Message Registers Figure 5-2. RX Message RoutingRx Message Registers Table 5-14. RxMessageID28Table 5-15. Rx Message ID28 Register Definitions Table 5-16. RxMessageID12Table 5-20. Rx Message Data Table 5-21. Rx Message Data 39 Register DefinitionsTable 5-22. Rx Message Data Table 5-23. Rx Message Data 23 Register DefinitionsTable 5-26. RxMessage RTR Table 5-27. Rx Message RTR Register DefinitionsTable 5-28. Rx Message Msg Flags Table 5-29. Rx Message Msg Flags Register DefinitionsError Count and Status Registers Table 5-30. Tx/Rx Error CountTable 5-31. Tx\Rx Error Count Register Definitions Table 5-32. Error StatusTable 5-34. Tx/Rx Message Level Register Table 5-35. Tx/Rx Message Level Register Definitionsrxlevel10 txlevel10Interrupt Flags Note The reset value of this register’s bits is indeterminateCRC Error Format ErrorInterrupt Enable Registers Table 5-38. Interrupt Enable RegistersTable 5-39. Interrupt Enable Register Definitions Bus Off State − int2n group error interruptsCAN Operating Mode Table 5-40. Interrupt Enable RegistersTable 5-41. Interrupt Enable Register Definitions Overload Condition − int3n group diagnostic interruptsCAN Configuration Registers Configuration Bit RateFigure 5-3. CAN Operating Mode Table 5-42. Bit Rate Divisor RegisterTable 5-44. Configuration Register Table 5-45. Configuration Register DefinitionsOverwrite Last Message CfgsjwBit Time tseg1 +tseg2 + time quanta TQAcceptance Filter and Acceptance Code Mask Table 5-46. Acceptance Filter Enable RegisterTable 5-47. Acceptance Filter Enable Register Definitions Table 5-48. Acceptance Mask 0 RegisterTable 5-50. Acceptance Mask Register ID Table 5-51. Acceptance Mask Register ID12 DefinitionsTable 5-52. Acceptance Mask Register Data D5556Table 5-54. Acceptance Code Register Table 5-55. Acceptance Code Register DefinitionsTable 5-56. Acceptance Mask Register ID12 Table 5-57. Acceptance Mask Register ID12 DefinitionsCANbus Analysis Arbitration Lost Capture RegisterTable 5-60. Arbitration Lost Capture Register Table 5-61. Arbitration Lost Capture Register DefinitionsError Capture Register Table 5-62. Error Capture RegisterTable 5-63. Error Capture Register Definitions ErrorcodeTable 5-65. Error Capture Register Definitions Frame Reference RegisterTable 5-64. Frame Reference Register Stuff Bit InsertedCAN Bus Interface Interface ConnectionsFigure 5-6. CAN Connector Figure 5-5. CAN Bus InterfaceFigure 5-7. Power for CAN +5CANGNDCAN +24VFigure 5-8. CAN Transceiver and Isolation Circuits 0.01uf
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