Datasheet

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DP83848T
7.2.7 PHY Control Register (PHYCR)
Table 27. PHY Control Register (PHYCR), address 0x19
Bit Bit Name Default Description
15 MDIX_EN Strap, RW Auto-MDIX Enable:
1 = Enable Auto-neg Auto-MDIX capability.
0 = Disable Auto-neg Auto-MDIX capability.
The Auto-MDIX algorithm requires that the Auto-Negotiation En-
able bit in the BMCR register to be set. If Auto-Negotiation is not
enabled, Auto-MDIX should be disabled as well.
14 FORCE_MDIX 0, RW Force MDIX:
1 = Force MDI pairs to cross.
(Receive on TPTD pair, Transmit on TPRD pair)
0 = Normal operation.
13 PAUSE_RX 0, RO Pause Receive Negotiated:
Indicates that pause receive should be enabled in the MAC. Based
on ANAR[11:10] and ANLPAR[11:10] settings.
This function shall be enabled according to IEEE 802.3 Annex 28B
Table 28B-3, “Pause Resolution”, only if the Auto-Negotiated High-
est Common Denominator is a full duplex technology.
12 PAUSE_TX 0, RO Pause Transmit Negotiated:
Indicates that pause transmit should be enabled in the MAC. Based
on ANAR[11:10] and ANLPAR[11:10] settings.
This function shall be enabled according to IEEE 802.3 Annex 28B
Table 28B-3, “Pause Resolution”, only if the Auto-Negotiated High-
est Common Denominator is a full duplex technology.
11 BIST_FE 0, RW/SC BIST Force Error:
1 = Force BIST Error.
0 = Normal operation.
This bit forces a single error, and is self clearing.
10 PSR_15 0, RW BIST Sequence select:
1 = PSR15 selected.
0 = PSR9 selected.
9 BIST_STATUS 0, LL/RO BIST Test Status:
1 = BIST pass.
0 = BIST fail. Latched, cleared when BIST is stopped.
For a count number of BIST errors, see the BIST Error Count in the
CDCTRL1 register.
8 BIST_START 0, RW BIST Start:
1 = BIST start.
0 = BIST stop.
7 BP_STRETCH 0, RW Bypass LED Stretching:
This will bypass the LED stretching and the LED will reflect the in-
ternal value.
1 = Bypass LED stretching.
0 = Normal operation.
6 RESERVED 0 RESERVED: Must be zero.