Datasheet

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8.0 Register Block (Continued)
1 RESERVED 0, RO Reserved: Writes as 0, read as 0
0 RESERVED 0, RO Reserved: Writes as 0, read as 0
Table 22. 10BASE-T Control & Status Register (10BTSCR) Address 18h
Bit Bit Name Default Description
15:14 RESERVED 0, RO Reserved: Writes ignored, read as 0
13 AUI_TPI 0, RO TREX Operating Mode:
This bit shows the current operating mode of TREX as chosen by
the Auto-Switch function.
1 = AUI mode
0 = TPI mode
12 RX_SERIAL Strap, RW 10BASE-T RX Serial Mode:
This bit is set according to the strap configuration of the
SERIAL10 pin at power-up/reset. After reset this bit may be writ-
ten to by software.
1 = 10BASE-T rx Serial mode selected
0 = 10BASE-T rx Nibble mode selected
Serial mode is not supported for 100 Mb/s operation.
11 TX_SERIAL Strap, RW 10BASE-T TX Serial Mode:
This bit is set according to the strap configuration of the
SERIAL_10 pin at power-up/reset. After reset this bit may be writ-
ten to by software.
1 = 10BASE-T tx Serial mode selected
0 = 10BASE-T tx Nibble mode selected
Serial mode is not supported for 100 Mb/s operation.
10 POL_DS 0, RW Polarity Detection & Correction Disable:
1 = Polarity Sense & Correction disabled
0 = Polarity Sense & Correction enabled
9 AUTOSW_EN 0, RW AUI/TPI Autoswitch:
1 = Enable autoswitch
0 = Disable autoswitch function
The use of autoswitch should be strictly limited to applications
that do not support Auto-Negotiation. Do not enable Auto-Nego-
tiation when enabling autoswitch as this may result in improper
operation.
8 LP_DS 0, RW Link Pulse Disable:
1 = Reception of link pulses ignored, good link condition forced
0 = Good link not forced, link pulses observed for good link
7 HB_DS 0, RW Heartbeat Disable:
1 = Heartbeat function disabled
0 = Heartbeat function enabled
When the device is configured for full duplex operation, this bit will
be ignored (the collision/heartbeat function has no meaning in
Full Duplex mode). HB_DS will read back as 1 if in Full Duplex
mode or Repeater mode.
Table 21. Loopback & Bypass Register (LBR) Address 17h (Continued)
Bit Bit Name Default Description