XRT83SL28
xr
8-CHANNEL E1 SHORT-HAUL LINE INTERFACE UNIT
REV. 1.0.0
HARDWARE MODE INTERFACE
NAME
PIN
TYPE
DESCRIPTION
SR/DR
2
I
Single Rail / Dual Rail Select Input
This pin is used to select Single Rail or Dual Rail data formats. By default,
Dual Rail is selected. To select Single Rail mode, this pin must be pulled
"High". Once this pin is pulled "High", TNEGn/CODEn can be used to select
between AMI and HDB3 Encoding/Decoding.
NOTE: Internally pulled "Low" with a 50kΩ resistor.
TERSEL1
TERSEL0
125
124
I
Termination Impedance Select
TERSEL[1:0] are used to set the internal impedance of the LIU for the Receive
and Transmit paths.
"00" = 75Ω for Tx and "High-Z" for Rx
"01" = 120Ω for Tx and "High-Z" for Rx
"10" = 75Ω for Tx and Rx
"11" = 120Ω for Tx and Rx
TCLKinv
RCLKinv
107
74
I
I
I
Transmit Clock Data
"Low" = TPOS/TNEG data is sampled on the falling edge of TCLK
"High" = TPOS/TNEG data is sampled on the rising edge of TCLK
NOTE: Internally pulled "Low" with a 50kΩ resistor.
Receive Clock Data
"Low" = RPOS/RNEG data is updated on the rising edge of RCLK
"High" = RPOS/RNEG data is updated on the falling edge of RCLK
NOTE: Internally pulled "Low" with a 50kΩ resistor.
LBM1
LBM0
56
57
Loop Back Mode Select
LBM[1:0] are used to configure the LIU into diagnostic loopback modes. To
select the channel number, see pins CHLB[3:0].
LBM1 LBM0
Loopback Mode
No Loopback
0
0
1
1
0
1
0
1
Analog Loopback
Remote Loopback
Digital Loopback
NOTE: Internally pulled "Low" with a 50kΩ resistor.
JASEL1
JASEL0
20
21
I
Jitter Attenuator Select
JASEL[1:0] are used to configure the jitter attenuator into the Receive or
Transmit path for all eight channels.
JASEL1 JASEL0
JA Select Mode
JA Disabled
0
0
1
1
0
1
0
1
Transmit Path
Receive Path
JA Disabled
NOTE: Internally pulled "Low" with a 50kΩ resistor.
10
EXAR [ EXAR CORPORATION ]
