Texas Instruments TNETX3270 specifications Internal wrap test

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TNETX3270

ThunderSWITCH24/3 ETHERNETSWITCH

WITH 24 10-MBIT/S PORTS AND 3 10-/100-MBIT/S PORTS

SPWS043B ± NOVEMBER 1997 ± REVISED APRIL 1999

pause frame transmission (continued)

Pause frames are transmitted if required, even if the port is observing the pausetime period from a pause frame it has received.

internal wrap test

Internal wrap mode causes some or all of the Ethernet MACs to be configured to loop back transmitted data into the receive path. This allows a frame to be sent into a designated source port and then selectively routed successively to and from ports involved in the test, before finally transmitting the frame out of the original port. By varying the number of ports between which the frame is forwarded, the potential fault capture area is expanded or constrained.

Intwrap in Systest determines which ports loop back. Ports 0 or 8 can be configured to not loop back, allowing them to be used as the start/end port for the test. Alternatively, the NM port (accessed via DIO) can be used for this purpose, with all MII ports configured to loop back.

For a frame to be forwarded from one port to another in this fashion, the switch must be programmed as follows:

DAssign a unique VID to each of the PortxQtag registers, and program these tags into the VLANnQID registers.

DThe VLANnports register associated with each of the VLANnQID registers should have only one bit set, indicating the port to which frames containing that IEEE Std 802.3 tag should be routed.

DRxacc and Txacc for each port must be 1. This causes the port to add the VID from its PortxQtag to the frame on reception, and strip the tag before transmission.

DThe destination address of the frames to be applied is not known, and UnkUniPorts and UnkMultiPorts should be all 1s.

This causes the following:

1.The VID from the source port PortxQtag register is added to the frame upon reception. As the address of the frame is unknown, it is forwarded to the AND of the appropriate VLANnports and Unkuniports (unicast) or Unkmultiports (multicast). As VLANnports should contain only a single 1, this should be a single port.

2.The frame is transmitted from the destination port selected in 1. Its VLAN tag is stripped beforehand; the frame loops back to the receive path.

3.Steps 1 and 2 are repeated, but the VID added upon reception is different from the one just stripped off at transmission. This means a different VLANnports register is used to determine the destination.

4.Eventually, the frame is sent to a port that is not configured for loopback and leaves the switch.

The operational status of the PHYs or external connections to the device do not have to be considered or assumed good when in internal loopback mode.

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Contents TNETX3270 ThunderSWITCH 24/3 ETHERNET Switch With 24 10-MBIT/S Ports and 3 10-/100-MBIT/S PortsWith 24 10-MBIT/S Ports and 3 10-/100-MBIT/S Ports DescriptionThunderSWITCH 24/3 ETHERNET ContentsPGV Package TOP View ThunderSWITCH  24/3Terminal Internal Description Name RESISTOR³ 10-/100-Mbit/s MAC interface ports 24±26³ Terminal Internal Description Name ResistorTerminal Functions 10-/100-Mbit/s MAC interface ports 24±26 ²Sdram interface Dras DcasDclk DrasHost DIO interface Serial MII management PHY interface Eeprom interfaceJtag interface Power interface Summary of signal terminals by signal group functionMiscellaneous DIO register groups Internal Register and Statistics Memory MapVlan Detailed DIO Register Map Byte DIO AddressSIO VLAN1QID VLAN0QID VLAN3QID VLAN2QIDVLAN5QID VLAN4QID VLAN7QID VLAN6QIDVLAN17QID VLAN16QID VLAN19QID VLAN18QIDVLAN21QID VLAN20QID VLAN23QID VLAN22QIDIntenable TNETX3270 reset reinitializes the TNETX3270 0x40000x5FFFFindnode23±16 Findnode31±24 Findnode39±32 Findnode47±40 Findcontrol Findnode7±0 Findnode15±8State of DIO signals during hardware reset Interface descriptionReceiving/transmitting management frames Network management port Frame format on the NM port Vlan ID FCSTpid TCI CRCMII serial management interface PHY management Mbit/s and 10-/100-Mbit/s MAC interface receive controlGiant long frames Short framesReceive filtering of frames Data transmissionTransmit control Adaptive performance optimization APO transmit pacingReceive versus transmit priority Uplink pretaggingSource-Port Pretag Encoding Source PortReceived Pretag Port Assignments TAGPort 27 NM Eeprom interface Edio TNETX3270 Eclk SCL SDAGND Outcome Stop Load Initd ² Fault LED Eclk Interaction of Eeprom load with the SIO registerSummary of Eeprom load outcomes Summary of Eeprom Load OutcomesJtag interface Jtag Instruction OpcodesHighz instruction LED interfaceHardware configurations LED Status Bit Definitions and Shift OrderLamp test Multi-LED displayMbit/s Interface Connections TNETX3270 TNETE2008 TerminalPort CLK Sync TXD3 M03TXD M04TXDM06TXD M03COLConnecting to TNETE2008 PHY² 10-/100-Mbit/s port configuration Switch TNETE2101 Terminal10-/100-Mbit/s MAC interfaces ports 24±26 100-Mbit/s Interface ConnectionsSpeed Configuration ± MxxFORCE10 Duplex Configuration ± MxxFORCEHD10-/100-Mbit/s port configuration in a nonmanaged switch 10-/100-Mbit/s port configuration in a managed switch Sdram interface TNETX3270 Terminal Interface to SDRAMs Sdram Terminals Not Driven by the TNETX3270Terminals Sdram Terminal Function TNETX3270 Held Sdram Terminal Terminal FunctionTNETX3270 State Terminal During Reset SDRAM-type and quantity indicationInitialization RefreshFrame routing Vlan supportIale Address maintenance Ieee Std 802.1Q headers ± receptionIeee Std 802.1Q headers ± transmission Spanning-tree support Aging algorithmsFrame-routing determination Frame-Routing Algorithm SPWS043B ± November 1997 ± Revised April Port mirroring CDEPort trunking/load sharing Flow controlCollision-based flow control Ieee Std 802.3 flow controlPause frame reception Internal wrap test Duplex wrap test PHY TNETX3270Copy to uplink Recommended operating conditions MIN NOM MAX UnitParameter Test Conditions MIN TYP MAX Unit Test measurement MIN MAX Unit Parameter MIN MAX Unit10-/100-Mbit/s MAC interface Timing requirements see Note 7 and Figure10-/100-Mbit/sreceive ports 24, 25 Timing requirements see Figure 10-/100-Mbit/stransmit ports 24, 25,Sdram command to command see Figure TdDA Delay time, from Dclk ↑ to DA Invalid Sdram subcycleDclk Dras DcasDIO/DMA interface DIO/DMA write cycleSDATA7± Z SDATA0 DIO/DMA read cycle Serial MII Management Read/Write Cycle Eeprom Parameter TNETX3150 TNETX3150A Unit MIN MAXTdLEDDATA Delay time, from LEDCLK↑ to 1st LED invalid ² During hard reset, Ledclk runs continuouslyPower-up Oscin and Reset Timing requirements see Figure TsuRESET Setup time Low before Oscin ↑ThRESET Hold time Low after Oscin ↑ TtOSCIN Transition time, Oscin rise and fallMechanical Data Important Notice
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