Freescale Semiconductor MPC860T user manual Reception Errors

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Freescale Semiconductor, Inc.

 

Table 3-4. Reception Errors

 

 

Error

Description

 

 

Overrun Error

The FEC maintains an internal FIFO for receiving data. If a receiver FIFO overrun occurs, the FEC

 

closes the buffer and sets RxBD[OV].

 

 

Non-Octet

The FEC handles up to seven dribbling bits when the receive frame terminates nonoctet aligned and

Error

it checks the CRC of the frame on the last octet boundary. If there is a CRC error, the frame nonoctet

(Dribbling Bits)

aligned (NO) error is reported in the RxBD. If there is no CRC error, no error is reported.

 

 

CRC Error

When a CRC error occurs with no dribbling bits, the FEC closes the buffer and sets RxBD[CR]. CRC

 

checking cannot be disabled, but the CRC error can be ignored if checking is not required.

 

 

Frame Length

When the receive frame length exceeds R_HASH[MAX_FRAME_LENGTH], I_EVENT[BABR] is set

Violation

indicating babbling receive error, and the LG bit in the end of frame RxBD is set.

 

Note: Receive frames exceeding 2047 bytes are truncated.

 

 

Freescale Semiconductor, Inc.

3-8MPC860T (Rev. D) Fast Ethernet Controller Supplement MOTOROLA

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MPC860T Rev. D Fast Ethernet Controller Freescale Semiconductor, IncMotorola Literature Distribution Centers Contents Parallel I/O Ports Contents Paragraph Title Number Illustrations Title NumberViii MPC860T Rev. D Fast Ethernet Controller Supplement Tables Number Document Revision History OverviewLists signiÞcant changes between revisions of this document Document Revision HistoryFeatures Comparison with the MPC8601 MPC860TBlock Diagram System Interface Unit SIU Embedded PowerPC Processor CoreFast Ethernet Controller Glueless System Design SIU Interrupt ConÞgurationInc FEC Signal Descriptions Signal DescriptionsName Pin Description L1RSYNCB MiimdcRXD3 MiitxerREJECT3 MIITXD2REJECT4 MIITXD1Freescale Semiconductor, Inc MII Signals Signal Description FEC Signal NameTransceiver Connection This chapter discusses the operation of the FECSerial Mode Connections to the External Transceiver FEC Frame TransmissionTXD0 RXD0FEC Frame Reception CAM Interface FEC Command Set Ethernet Address Recognition Hash Table Algorithm Rcntrlprom =Inter-Packet Gap Time Collision HandlingEthernet Error-Handling Procedure Transmission ErrorsReception Errors Internal and External LoopbackReception Errors Chapter Parallel I/O Ports Port D Pin FunctionsEnabling MII Mode Signal FunctionPort D Registers Shows the port D pin assignmentsSdma Registers CLKDescribes Sdcr Þelds Sdcr Field DescriptionsFRZ Faid RAID BitsParameter RAM Brießy describes each enter in the FEC parameter RAMFEC Parameter RAM Memory Map Address Name Description SectionRAM Perfect Match Address Low Register Addrlow RAM Perfect Match Address High Addrhigh RAM Hash Table High HashtablehighDescribes the Addrlow Þelds Describes the Addrhigh ÞeldsRAM Hash Table Low Hashtablelow Describes Hashtablehigh ÞeldsHashtablehigh Field Descriptions HashhighBeginning of RxBD Ring Rdesstart Beginning of TxBD Ring XdesstartDescribes Hashtablelow Þelds Describes Rdesstart ÞeldsDescribes Xdesstart Þelds Receive Buffer Size Register RbuffsizeXdesstart Field Descriptions Spare Fecpin Etheren Reset MUX Ethernet Control Register EcntrlDescribes Rbuffsize Þelds Rbuffsize Field DescriptionsInterrupt Event IEVENT/Interrupt Mask Register Imask Describes Ecntrl ÞeldsEcntrl Field Descriptions FecpinmuxEthernet Interrupt Vector Register Ivec Rfint to notify at the end of frame10. IEVENT/IMASK Field Descriptions HberrRxBD Active Register Rdesactive 11 describes Ivec Þelds11. Ivec Field Descriptions Ilevel12 describes Rdesactive Þelds TxBD Active Register Xdesactive12. Rdesactive Field Descriptions 13 describes Xdesactive Þelds MII Management Frame Register Miidata13. Xdesactive Field Descriptions 14 describes Miidata Þelds 14. Miidata Field DescriptionsMII Speed Control Register Miispeed 15 describes Miispeed Þelds15. Miispeed Field Descriptions Dispreamble MiispeedFifo Receive Bound Register Rbound 17 describes Rbound Þelds16. Programming Examples for Miispeed Register 17. Rbound Field DescriptionsFifo Receive Start Register Rfstart Transmit Watermark Register Xwmrk18 describes Rñfstart Þelds 18. Rfstart Field Descriptions19 bit Þeld descriptions for Xwmrk Fifo Transmit Start Register Xfstart19. Xwmrk Field Descriptions DMA Function Code Register Funcode 20 describes Xfstart Þelds20. Xfstart Field Descriptions DATABO0 DATABO1 DESCBO0 DESCBO1 FC1 FC2 FC3Receive Control Register Rcntrl 21 describes Funcode Þelds21. Funcode Field Descriptions DescboReceive Hash Register Rhash 22 describes Rcntrl Þelds22. Rcntrl Field Descriptions BcrejTransmit Control Register Xcntrl 22 describes Rhash Þelds24 describes Xcntrl Þelds 23. Rhash Field DescriptionsUser Initialization before Setting Ecntrletheren Initialization SequenceHardware Initialization 25. Hardware Initialization27. User Initialization before Setting Ecntrletheren Descriptor Controller InitializationUser Initialization after Asserting Ecntrletheren Step Description27. User Initialization after Setting Ecntrletheren Buffer Descriptors BDsEthernet Receive Buffer Descriptor RxBD StepRxBD format is shown in Table 27. Receive Buffer Descriptor RxBD Field DescriptionRO1 RO2 Data Length RO1Ethernet Transmit Buffer Descriptor TxBD 29 describes TxBD Þelds29. Transmit Buffer Descriptor TxBD Field Descriptions TO1 TO2 DEF CSLXcntrlhbc = DataFreescale Semiconductor, Inc DC Electrical Characteristics AC Electrical CharacteristicsMII Receive Signal Timing RXD30, RXDV, RXER, Rxclk Electrical SpeciÞcationsMII Transmit Signal Timing TXD30, TXEN, TXER, Txclk MII Receive Signal TimingMII Transmit Signal Timing Num Characteristic Min Max UnitMII Async Inputs Signal Timing CRS, COL MII Async Inputs Signal TimingTxen Txer CRS, COLShows the MII serial management channel timing diagram MII Serial Management Channel TimingFollowing pins are marked as spare on MPC860T Pin AssignmentsFreescale Semiconductor, Inc Freescale Semiconductor, Inc For More Information On This Product
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