Ds1874 sfp+ controller with digital ldd interface – Rainbow Electronics DS1874 User Manual
Page 40

DS1874
SFP+ Controller with Digital LDD Interface
40
______________________________________________________________________________________
POWER-ON
VALUE
X0XX
0XXXb
READ
ACCESS
All
WRITE
ACCESS
See
below
MEMORY
TYPE
Volatile
Write
Access
N/A All N/A All All N/A N/A N/A
6Eh
TXDS TXDC IN1S RSELS
RSELC TXF RXL RDYB
BIT
7
BIT
0
BIT
7
TXDS: TXD Status Bit. Reflects the logic state of the TXD pin (read only).
0 = TXD pin is logic-low.
1 = TXD pin is logic-high.
BIT
6
TXDC: TXD Software Control Bit. This bit allows for software control that is identical to the TXD pin.
See the section on TXD for further information. Its value is wire-ORed with the logic value of the
TXD pin (writable by all users).
0 = (Default).
1 = Forces the device into a TXD state regardless of the value of the TXD pin.
BIT
5
IN1S: IN1 Status Bit. Reflects the logic state of the IN1 pin (read only).
0 = IN1 pin is logic-low.
1 = IN1 pin is logic-high.
BIT
4
RSELS: RSEL Status Bit. Reflects the logic state of the RSEL pin (read only).
0 = RSEL pin is logic-low.
1 = RSEL pin is logic-high.
BIT
3
RSELC: RSEL Software Control Bit. This bit allows for software control that is identical to the RSEL
pin. Its value is wire-ORed with the logic value of the RSEL pin to create the RSELOUT pin’s logic
value (writable by all users).
0 = (Default).
1 = Forces the device into a RSEL state regardless of the value of the RSEL pin.
BIT
2
TXF: Reflects the driven state of the TXF pin (read only).
0 = TXF pin is driven low.
1 = TXF pin is pulled high.
BIT
1
RXL: Reflects the driven state of the LOSOUT pin (read only).
0 = LOSOUT pin is driven low.
1 = LOSOUT pin is pulled high.
BIT
0
RDYB: Ready Bar.
0 = V
CC
is above POA.
1 = V
CC
is below POA and/or too low to communicate over the I
2
C bus.
Lower Memory, Register 6Eh: STATUS