TBR1: 10BASE-T Status Register (Register 1)
The Status Register identifies the physical and Auto-
negotiation capabilities of the local PHY. This register is
read only; a write will have no effect.
Table 66. TBR1: 10BASE-T PHY Status Register (Register 1)
Read/Write
Default
Value
Bits
Name
Description
(Note 1)
1 = 100BASE-T4 able,
0 = not 100BASE-T4 able
15
100BASE-T4
RO
0
0
0
1
1 = 100BASE-X full-duplex able,
0 = not 100BASE-X full-duplex able
14
13
12
100BASE-X Full-Duplex
100BASE-X Half-Duplex
10 Mbps Full-Duplex
RO
RO
RO
1 = 100BASE-X half-duplex able,
0 = not 100BASE-X half-duplex able
1 = 10 Mbps full-duplex able,
0 = not 10 Mbps full-duplex able
1 = 10 Mbps half-duplex able,
0 = not 10 Mbps half-duplex able
11
10 Mbps Half-Duplex
Reserved
RO
RO
1
10-7
Ignore when read
NA
1 = PHY can accept management (mgmt)
frames with or without preamble, 0 = PHY
can only accept mgmt frames with
preamble
6
MF Preamble Suppression
RO
1
1 = Auto-Negotiation completed,
0 = Auto-Negotiation not completed
5
4
3
2
1
0
Auto-Negotiation Complete
Remote Fault
RO
RO, LH
RO
0
0
1
0
0
1
1 = remote fault detected,
0 = no remote fault detected
1 = PHY able to auto-negotiate,
0 = PHY not able to auto-negotiate
Auto-Negotiation Ability
Link Status
1 = link is up,
0 = link is down
RO, LL
RO
1 = jabber condition detected,
0 = no jabber condition detected
Jabber Detect
1 = extended register capabilities,
0 = basic register set capabilities only
Extended Capability
RO
Note:
1. LH = Latching High, LL = Latching Low.
190
Am79C978
AMD [ AMD ]
