Texas Instruments TMS320DM36X manual Back Off Test Register Bofftest

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Ethernet Media Access Controller (EMAC) Registers

5.39 Back Off Test Register (BOFFTEST)

The back off test register (BOFFTEST) is shown in Figure 78 and described in Table 76.

Figure 78. Back Off Random Number Generator Test Register (BOFFTEST)

31

 

 

26

25

16

 

Reserved

 

 

 

RNDNUM

 

 

 

 

 

 

 

R-0

 

 

 

R-0

15

12

11

10

9

0

 

 

 

 

 

 

COLLCOUNT

Reserved

 

TXBACKOFF

 

 

 

 

 

 

 

R-0

 

R-0

 

R-0

LEGEND: R = Read only; -n= value after reset

Table 76. Back Off Test Register (BOFFTEST) Field Descriptions

Bit

Field

Value

Description

 

 

 

 

31-26

Reserved

0

Reserved

 

 

 

 

25-16

RNDNUM

0-3FFh

Backoff random number generator. This field allows the Backoff Random Number Generator to be

 

 

 

read. Reading this field returns the generator's current value. The value is reset to 0 and begins

 

 

 

counting on the clock after the deassertion of reset.

 

 

 

 

15-12

COLLCOUNT

0-Fh

Collision count. These bits indicate the number of collisions the current frame has experienced.

 

 

 

 

11-10

Reserved

0

Reserved

 

 

 

 

9-0

TXBACKOFF

0-3FFh

Backoff count. This field allows the current value of the backoff counter to be observed for test

 

 

 

purposes. This field is loaded automatically according to the backoff algorithm, and is decremented

 

 

 

by one for each slot time after the collision.

 

 

 

 

5.40 Transmit Pacing Algorithm Test Register (TPACETEST)

The transmit pacing algorithm test register (TPACETEST) is shown in Figure 79 and described in Table 77.

Figure 79. Transmit Pacing Algorithm Test Register (TPACETEST)

31

 

 

16

 

Reserved

 

 

 

 

 

 

 

R-0

 

 

15

5

4

0

 

 

 

 

Reserved

 

 

PACEVAL

 

 

 

 

R-0

 

 

R-0

LEGEND: R = Read only; -n= value after reset

Table 77. Transmit Pacing Algorithm Test Register (TPACETEST) Field Descriptions

Bit

Field

Value

Description

 

 

 

 

31-5

Reserved

0

Reserved

 

 

 

 

4-0

PACEVAL

0-1Fh

Pacing register current value. A nonzero value in this field indicates that transmit pacing is active. A

 

 

 

transmit frame collision or deferral causes PACEVAL to be loaded with 1Fh (31); good frame

 

 

 

transmissions (with no collisions or deferrals) cause PACEVAL to be decremented down to 0. When

 

 

 

PACEVAL is nonzero, the transmitter delays four Inter Packet Gaps between new frame transmissions

 

 

 

after each successfully transmitted frame that had no deferrals or collisions. If a transmit frame is

 

 

 

deferred or suffers a collision, the IPG time is not stretched to four times the normal value. Transmit

 

 

 

pacing helps reduce capture effects, which improves overall network bandwidth.

 

 

 

 

SPRUFI5B –March 2009 –Revised December 2010 Ethernet Media Access Controller (EMAC)/Management Data Input/Output 117

Submit Documentation Feedback

(MDIO)

 

© 2009–2010, Texas Instruments Incorporated

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Contents Users Guide Submit Documentation Feedback Mdio Registers Mdio Version Register Version Mdio Control Register Control Appendix B Appendix aList of Figures Transmit Interrupt Mask Set Register Txintmaskset List of Tables MAC Control Register Maccontrol Field Descriptions Read This First Related Documentation From Texas Instruments Related Documentation From Texas Instruments Purpose of the Peripheral FeaturesEmac and Mdio Block Diagram Functional Block DiagramIndustry Standards Compliance Statement Clock ControlMII Clocking Signal Descriptions Memory MapMedia Independent Interface MII Connections Emac and Mdio Signals for MII Interface Signal Type DescriptionPin Multiplexing Ethernet Frame Format Ethernet Protocol OverviewEthernet Frame Description Field Bytes DescriptionProgramming Interface Ethernet’s Multiple Access ProtocolPacket Buffer Descriptors WordField Field Description Basic Descriptor DescriptionTransmit and Receive Descriptor Queues Transmit and Receive Emac Interrupts Example 1. Transmit Buffer Descriptor in C Structure Format Transmit Buffer Descriptor FormatBuffer Pointer Next Descriptor PointerBuffer Offset Buffer LengthOwnership Owner Flag End of Packet EOP FlagEnd of Queue EOQ Flag Teardown Complete Tdowncmplt FlagReceive Buffer Descriptor Format Receive Buffer Descriptor FormatExample 2. Receive Buffer Descriptor in C Structure Format Buffer Length Alignment Error Alignerror Flag Code Error Codeerror FlagCRC Error Crcerror Flag Jabber FlagInternal Memory Emac Control ModuleBus Arbiter CPUInterrupt Control Transmit Pulse InterruptReceive Pulse Interrupt Receive Threshold Pulse Interrupt Miscellaneous Pulse InterruptInterrupt Pacing Mdio Module Components Mdio ModuleMdio Clock Generator Global PHY Detection and Link State MonitoringPHY Register User Access Active PHY MonitoringMdio Module Operational Overview Initializing the Mdio Module Writing Data To a PHY RegisterReading Data From a PHY Register Example 3. Mdio Register Access Macros Example of Mdio Register Access CodeEmac Module Components Emac ModuleReceive DMA Engine Receive FifoMAC Receiver Clock and Reset LogicReceive Address Transmit DMA EngineEmac Module Operational Overview Data Reception Media Independent Interface MIIReceive Control Receive Inter-Frame IntervalIeee 802.3x-Based Receive Buffer Flow Control Collision-Based Receive Buffer Flow ControlCRC Insertion Transmit ControlAdaptive Performance Optimization APO Interpacket-Gap IPG EnforcementSpeed, Duplex, and Pause Frame Support Transmit Flow ControlReceive DMA Host Configuration Packet Receive OperationReceive Channel Enabling Hardware Receive QOS Support Receive Address MatchingHost Free Buffer Tracking Receive Channel TeardownReceive Frame Classification Promiscuous Receive Mode Receive Frame Treatment SummaryReceive Frame Treatment Receive Overrun Middle of Frame Overrun TreatmentMiddle of Frame Overrun Treatment Packet Transmit Operation Transmit DMA Host ConfigurationReceive and Transmit Latency Transmit Channel TeardownReset Considerations Software Reset ConsiderationsTransfer Node Priority Initialization Hardware Reset ConsiderationsEnabling the EMAC/MDIO Peripheral Emac Control Module InitializationExample 4. Emac Control Module Initialization Code Example 5. Mdio Module Initialization Code Mdio Module InitializationEmac Module Initialization Emac Module Interrupt Events and Requests Interrupt SupportReceive Threshold Interrupts Transmit Packet Completion InterruptsReceive Packet Completion Interrupts Statistics Interrupt Host Error InterruptMdio Module Interrupt Events and Requests User Access Completion InterruptLink Change Interrupt Proper Interrupt ProcessingEmulation Considerations Power ManagementEmulation Control Soft Free DescriptionSlave Vbus Emac Control Module RegistersAcronym Register Description Bit Field Value DescriptionSoftreset Emac Control Module Software Reset Register CmsoftresetEmac Control Module Emulation Control Register Cmemcontrol Soft FreeEmac Control Module Interrupt Control Register Cmintctrl IntpaceenIntprescale Rxpulseen RxthreshenTxpulseen Statpendinten Hostpendinten Linkinten Userinten Bit FieldStatpendinten Rxpulseinttstat Rxthreshinttstat31-8 Reserved TXPULSEINTTSTATn TxpulseinttstatStatpendintstat Statpendintstat Hostpendintstat Linkintstat UserintstatTximax RximaxMdio Version Register Version Management Data Input/Output Mdio RegistersMdio Version Register Version Field Descriptions Mdio Control Register Control Field Descriptions Mdio Control Register ControlPHY Link Status Register Link PHY Acknowledge Status Register AlivePHY Acknowledge Status Register Alive Field Descriptions PHY Link Status Register Link Field Descriptions31-2 Reserved Will clear the event and writing a 0 has no effect No Mdio user command complete event USERINTMASKED0 and USERINTMASKED1 correspond to USERACCESS0 W1S-0 Mdio User Command Complete Interrupt Mask Clear Register Mdio User Command Complete Interrupt Mask Clear RegisterMdio User Access Register 0 USERACCESS0 Field Descriptions Mdio User Access Register 0 USERACCESS0Linksel Linkintenb Mdio User PHY Select Register 0 USERPHYSEL0Phyadrmon LinkselMdio User Access Register 1 USERACCESS1 Field Descriptions Mdio User Access Register 1 USERACCESS1Mdio User PHY Select Register 1 USERPHYSEL1 Mdio User PHY Select Register 1 USERPHYSEL1Ethernet Media Access Controller Emac Registers Offset Acronym Register Description Network Statistics Registers Transmit Identification and Version Register Txidver Transmit Control Register TxcontrolTransmit Control Register Txcontrol Field Descriptions Transmit Teardown Register Txteardown Transmit Teardown Register Txteardown Field DescriptionsTxtdnch Rxident Receive Identification and Version Register RxidverRxmajorver Rxminorver RxmajorverReceive Teardown Register Rxteardown Receive Control Register RxcontrolReceive Control Register Rxcontrol Field Descriptions Receive Teardown Register Rxteardown Field DescriptionsTX7PEND Transmit Interrupt Status Unmasked Register TxintstatrawTransmit Interrupt Status Masked Register Txintstatmasked Transmit Interrupt Status Masked Register TxintstatmaskedTX7MASK Transmit Interrupt Mask Set Register TxintmasksetTransmit Interrupt Mask Clear Register Txintmaskclear Transmit Interrupt Mask Clear Register TxintmaskclearMAC End Of Interrupt Vector Register Maceoivector MAC Input Vector Register MacinvectorMAC Input Vector Register Macinvector Field Descriptions StatpendRX7PEND Receive Interrupt Status Unmasked Register RxintstatrawReceive Interrupt Status Masked Register Rxintstatmasked Receive Interrupt Status Masked Register RxintstatmaskedRX7MASK Receive Interrupt Mask Set Register RxintmasksetReceive Interrupt Mask Clear Register Rxintmaskclear Receive Interrupt Mask Clear Register RxintmaskclearMAC Interrupt Status Unmasked Register Macintstatraw MAC Interrupt Status Masked Register MacintstatmaskedHostpend Statpend MAC Interrupt Mask Clear Register Macintmaskclear MAC Interrupt Mask Set Register MacintmasksetHostmask Statmask HostmaskRxcmfen Rxpasscrc Rxqosen RxnochainRxcsfen Rxcefen Rxcafen RxpromchFrames containing errors are filtered Receive multicast channel select RXCH7EN Receive Unicast Enable Set Register RxunicastsetReceive Unicast Clear Register Rxunicastclear Receive Unicast Clear Register RxunicastclearReceive Maximum Length Register Rxmaxlen Receive Buffer Offset Register RxbufferoffsetReceive Maximum Length Register Rxmaxlen Field Descriptions Rxfilterthresh Receive Channel 0-7 Free Buffer Count Register RXnFREEBUFFER MAC Control Register Maccontrol Field Descriptions MAC Control Register MaccontrolRxbufferflowen TxflowenLoopback FullduplexMAC Status Register Macstatus Field Descriptions MAC Status Register MacstatusRxqosact Fifo Control Register Fifocontrol Emulation Control Register EmcontrolEmulation Control Register Emcontrol Field Descriptions Fifo Control Register Fifocontrol Field DescriptionsSoft Reset Register Softreset MAC Configuration Register MacconfigMAC Configuration Register Macconfig Field Descriptions Soft Reset Register Softreset Field DescriptionsMAC Source Address High Bytes Register Macsrcaddrhi MAC Source Address Low Bytes Register MacsrcaddrloMAC Hash Address Register 2 MACHASH2 MAC Hash Address Register 1 MACHASH1MAC Hash Address Register 1 MACHASH1 Field Descriptions MAC Hash Address Register 2 MACHASH2 Field DescriptionsBack Off Test Register Bofftest Transmit Pacing Algorithm Test Register TpacetestBack Off Test Register Bofftest Field Descriptions Transmit Pause Timer Register Txpause Receive Pause Timer Register RxpauseReceive Pause Timer Register Rxpause Field Descriptions Transmit Pause Timer Register Txpause Field DescriptionsMAC Address Low Bytes Register Macaddrlo Field Descriptions MAC Address Low Bytes Register MacaddrloValid Matchfilt Channel MACADDR0 MACADDR1 ValidMAC Index Register Macindex MAC Address High Bytes Register MacaddrhiMAC Index Register Macindex Field Descriptions MACADDR2 MACADDR3 MACADDR4 MACADDR5TXnHDP Receive Channel 0-7 Completion Pointer Register RXnCP Transmit Channel 0-7 Completion Pointer Register TXnCPGood Receive Frames Register Rxgoodframes Network Statistics RegistersBroadcast Receive Frames Register Rxbcastframes Multicast Receive Frames Register RxmcastframesReceive Alignment/Code Errors Register Rxaligncodeerrors Receive CRC Errors Register RxcrcerrorsPause Receive Frames Register Rxpauseframes Receive Oversized Frames Register RxoversizedReceive Undersized Frames Register Rxundersized Receive Jabber Frames Register RxjabberReceive Frame Fragments Register Rxfragments Filtered Receive Frames Register RxfilteredReceive Octet Frames Register Rxoctets Receive QOS Filtered Frames Register RxqosfilteredGood Transmit Frames Register Txgoodframes Broadcast Transmit Frames Register TxbcastframesDeferred Transmit Frames Register Txdeferred Pause Transmit Frames Register TxpauseframesTransmit Collision Frames Register Txcollision Transmit Single Collision Frames Register TxsinglecollTransmit Carrier Sense Errors Register Txcarriersense Transmit Underrun Error Register TxunderrunTransmit Late Collision Frames Register Txlatecoll Transmit Octet Frames Register TxoctetsSubmit Documentation Feedback Receive DMA Overruns Register Rxdmaoverruns Network Octet Frames Register NetoctetsAppendix a Glossary Term Definition Physical Layer DefinitionsReference Additions/Modifications/Deletions Document Revision HistoryProducts Applications DSPRfid
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