AM79C901AJCT AMD [Advanced Micro Devices], AM79C901AJCT Datasheet - Page 57

• Manufacturer Part Number: AM79C901AJCT
• Description: HomePHY Single-Chip 1/10 Mbps Home Networking PHY
• Manufacturer: AMD [Advanced Micro Devices]

TBR0: 10BASE-T PHY Control Register (Register 0)
Notes:
1. R/W = Read/Write, SC = Self Clearing, R = Read only.
2. Soft Reset does not reset the PDX block. Refer to the Soft Reset section for details.
3. Bits 8 and 13 have no effect if Auto-Negotiation is enabled (Bit 12 = 1).
4. If the ISOL pin of the chip and the Isolate bit in Register 0 is 1, this bit will be set.
5. The “enable loopback mode” bit must also be set to ensure that collision traffic is not imposed on the network.
Bits
6:0
15
14
13
12
11
10
9
8
7
Soft Reset (Note 2)
Enable Loopback Mode
Speed Selection
(Note 3)
Auto-Negotiation Enable
Power Down
Isolate
(Note 4)
Restart Auto-Negotiation
Duplex Mode
(Note 3)
Collision Test
(Note 5)
Reserved
Name
Table 41. TBR0: 10BASE-T PHY Control Register (Register 0)
When write
1 = PHY software reset
0 = Normal operation
When read
1 = Reset in process
0 = Reset done
1 = Loopback mode enable
0 = Loopback mode disable
1 = 100 Mbps (not available)
0 = 10 Mbps
1 = Enable Auto-Negotiation
0 = Disable Auto-Negotiation
1 = Power down
0 = Normal operation
1 = Electrically isolates PHY from the MII/GPSI
0 = Normal operation
1 = Restart Auto-Negotiation
0 = Normal operation
1 = Full-Duplex
0 = Half-Duplex
1 = Enable COL signal test
0 = Disable COL signal test
Write as 0, ignore on read
P R E L I M I N A R Y
Am79C901A
Description
Read/Write
(Note 1)
R/W, SC
R/W, SC
R/W
R/W
R/W
R/W
R/W
R/W
R
R
Default
Value
(hex)
0
0
0
1
0
1
0
1
0
0
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