Datasheet

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DP83848T
7.1.2 Basic Mode Status Register (BMSR)
7 Collision Test 0, RW Collision Test:
1 = Collision test enabled.
0 = Normal operation.
When set, this bit will cause the COL signal to be asserted in response
to the assertion of TX_EN within 512-bit times. The COL signal will be
de-asserted within 4-bit times in response to the de-assertion of
TX_EN.
6:0 RESERVED 0, RO RESERVED: Write ignored, read as 0.
Table 13. Basic Mode Status Register (BMSR), address 0x01
Bit Bit Name Default Description
15 100BASE-T4 0, RO/P 100BASE-T4 Capable:
0 = Device not able to perform 100BASE-T4 mode.
14 100BASE-TX
Full Duplex
1, RO/P 100BASE-TX Full Duplex Capable:
1 = Device able to perform 100BASE-TX in full duplex mode.
13 100BASE-TX
Half Duplex
1, RO/P 100BASE-TX Half Duplex Capable:
1 = Device able to perform 100BASE-TX in half duplex mode.
12 10BASE-T
Full Duplex
1, RO/P 10BASE-T Full Duplex Capable:
1 = Device able to perform 10BASE-T in full duplex mode.
11 10BASE-T
Half Duplex
1, RO/P 10BASE-T Half Duplex Capable:
1 = Device able to perform 10BASE-T in half duplex mode.
10:7 RESERVED 0, RO RESERVED: Write as 0, read as 0.
6MF Preamble
Suppression
1, RO/P Preamble suppression Capable:
1 = Device able to perform management transaction with preamble
suppressed, 32-bits of preamble needed only once after reset, invalid
opcode or invalid turnaround.
0 = Normal management operation.
5 Auto-Negotiation Com-
plete
0, RO Auto-Negotiation Complete:
1 = Auto-Negotiation process complete.
0 = Auto-Negotiation process not complete.
4 Remote Fault 0, RO/LH Remote Fault:
1 = Remote Fault condition detected (cleared on read or by reset).
Fault criteria: Far End Fault Indication or notification from Link Part-
ner of Remote Fault.
0 = No remote fault condition detected.
3 Auto-Negotiation Abili-
ty
1, RO/P Auto Negotiation Ability:
1 = Device is able to perform Auto-Negotiation.
0 = Device is not able to perform Auto-Negotiation.
2 Link Status 0, RO/LL Link Status:
1 = Valid link established (for either 10 or 100 Mb/s operation).
0 = Link not established.
The criteria for link validity is implementation specific. The occurrence
of a link failure condition will causes the Link Status bit to clear. Once
cleared, this bit may only be set by establishing a good link condition
and a read via the management interface.
Table 12. Basic Mode Control Register (BMCR), address 0x00 (Continued)
Bit Bit Name Default Description