lxt975 Intel Corporation, lxt975 Datasheet - Page 64

• Manufacturer Part Number: lxt975
• Description: Fast Ethernet 10/100 Quad Transceivers
• Manufacturer: Intel Corporation

LXT974/LXT975 — Fast Ethernet 10/100 Quad Transceivers
64
0.15
0.14
0.13
0.12
0.11
0.10
0.9
0.8
0.7
0.6:4
0.3
0.2
0.1:0
1. R/W = Read/Write
2. If auto-negotiation is enabled, this bit is ignored. If auto-negotiation is disabled, the default value of bit 0.13 is determined by
3. If SD_TXn is tied High or to a 5V PECL input (FX Mode), the default value of bit 0.12 = 0. If SD_TXn is tied Low (TP Mode),
4. The LXT974/975 internally holds all set values of the configuration registers upon exiting power down mode. A delay of 500
5. The default value of bit 0.10 is determined by pin TRSTEn.
6. If auto-negotiation is enabled, the default value of bit 0.9 is determined by CFG_0.
7. If auto-negotiation is enabled, this bit is ignored. If auto-negotiation is disabled and the port is operating in TX mode, the
8. This bit is ignored unless loopback is enabled (bit 0.14 = 1).
Bit
RO = Read Only
SC = Self Clearing
CFG_0.
the default value of bit 0.12 is determined by AUTOENA.
ns minimum is required from the time power down is cleared until any register can be written.
If auto-negotiation is disabled, the bit is ignored.
default value of bit 0.8 is determined by pin FDE. If auto-negotiation is disabled and the port is operating in FX mode, the
default value of bit 0.8 is determined by pin FDE_FX.
Table 44. Control Register
Reset
Loopback
Speed
Selection
Auto-Negotiation
Enable
Power Down
Isolate
Restart Auto-
Negotiation
Duplex Mode
Collision Test
Transceiver Test
Mode
Master-Slave
Enable
Master-Slave Value
Reserved
Name
1 = Reset port.
0 = Enable normal operation.
1 = Enable loopback mode.
0 = Disable loopback mode.
1 = 100 Mbps.
0 = 10 Mbps.
1 = Enable auto-negotiate process (overrides speed select and
duplex mode bits).
0 = Disable auto-negotiate process.
1 = Enable power down.
0 = Enable normal operation.
1 = Electrically isolate port from MII.
0 = Normal operation.
1 = Restart auto-negotiation process.
0 = Normal operation.
1 = Enable full-duplex.
0 = Enable half-duplex.
1 = Enable COL signal test.
0 = Disable COL signal test.
Not supported.
Not supported.
Not supported.
Write as 0; ignore on read.
Description
Type
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
RO
RO
RO
SC
SC
1
Datasheet
Default
Note 2
Note 3
Note 4
Note 5
Note 6
Note 7
Note 8
N/A
0
0
0
0
0