LXT972 Level One, LXT972 Datasheet - Page 62

• Manufacturer Part Number: LXT972
• Description: 3.3V Dual-Speed Fast Ethernet Transceiver Datasheet
• Manufacturer: Level One

LXT972 3.3V Dual-Speed Fast Ethernet Transceiver
Table 50: LED Configuration Register (Address 20, Hex 14)
62
20.15:12 LED1
20.11:8
1. R/W = Read /Write
2. Link status is the primary LED driver. The LED is asserted (solid ON) when the link is up.
3. Combined event LED settings are not affected by Pulse Stretch bit 20.1. These display settings are stretched regardless of the value of 20.1.
4. Duplex status is the primary LED driver. The LED is asserted (solid ON) when the link is full duplex.
5. Values are relative approximations. Not guaranteed or production tested.
Bit
RO = Read Only
LH = Latching High
The secondary LED driver (Receive or Activity) causes the LED to change state (blink).
Collision status is the secondary LED driver. The LED changes state (blinks) when a collision occurs.
Programming
bits
LED2
Programming
bits
Name
0000 = Display Speed Status (Continuous, Default)
0001 = Display Transmit Status (Stretched)
0010 = Display Receive Status (Stretched)
0011 = Display Collision Status (Stretched)
0100 = Display Link Status (Continuous)
0101 = Display Duplex Status (Continuous)
0110 = Unused
0111 = Display Receive or Transmit Activity (Stretched)
1000 = Test mode- turn LED on (Continuous)
1001 = Test mode- turn LED off (Continuous)
1010 = Test mode- blink LED fast (Continuous)
1011 = Test mode- blink LED slow (Continuous)
1100 = Display Link and Receive Status combined
1101 = Display Link and Activity Status combined
1110 = Display Duplex and Collision Status combined
1111 = Unused
0000 = Display Speed Status
0001 = Display Transmit Status
0010 = Display Receive Status
0011 = Display Collision Status
0100 = Display Link Status (Default)
0101 = Display Duplex Status
0110 = Unused
0111 = Display Receive or Transmit Activity
1000 = Test mode- turn LED on
1001 = Test mode- turn LED off
1010 = Test mode- blink LED fast
1011 = Test mode- blink LED slow
1100 = Display Link and Receive Status combined
1101 = Display Link and Activity Status combined
1110 = Display Duplex and Collision Status combined
1111 = Unused
Description
2
2
2
2
(Stretched)
(Stretched)
(Stretched)
(Stretched)
4
4
(Stretched)
(Stretched)
3
3
3
3
3
3
Type
R/W
R/W
1
Default
0000
0100