TNETX3151 datasheet(48/65 Pages) TI1

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TNETX3151

ThunderSWITCH

™ 12/3 ETHERNET™ SWITCH

WITH 12 10-MBIT/S PORTS AND 3 10-/100-MBIT/S PORTS

SPWS048A – MARCH 1998 – REVISED APRIL 1999

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

TNETX3151

Figure 9. Internal Wrap Example

duplex wrap test

Duplex wrap test is similar to internal wrap mode (see Figure 10). The ports can be set to accept frame data

that is wrapped at the PHY. This permits network connections between the device and the PHY to be verified.

Any port can be the source port (not just the NM port as shown in Figure 9). By using multicast/broadcast frames,

traffic can be routed selectively between ports involved in the test or return the frame directly before

retransmission on the uplink. Software control of the external PHYs is required to configure them for loopback.

If the internal PCS is in use (port configured in PMA mode) loopback in PCSxcontrol also must be asserted. This

causes MxxEWRAP to be high, forcing external PMD into loopback mode.

Duplex frame-wrap test mode is selected by setting dpwrap in Systest. When selected, the port is forced into

full duplex, allowing it to receive frames it transmits.

The switch is configured in the same manner as internal wrap.

TNETX3151

PHY

Figure 10. Duplex Wrap Example

TNETX3151 数据表(PDF) 48 Page - Texas Instruments