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XRT86VL30
147
SINGLE T1/E1/J1 FRAMER/LIU COMBO - T1 REGISTER DESCRIPTION
REV. 1.0.1
TABLE 129: LIU CHANNEL CONTROL REGISTER 2 (LIUCCR2)
HEX ADDRESS: 0X0F02
BIT
FUNCTION
TYPE
DEFAULT
DESCRIPTION-OPERATION
7
INVQRSS_n
R/W
0
Invert QRSS Pattern:
This bit inverts the output PRBS/QRSS pattern if the LIU Block is
configured to transmit a PRBS/QRSS pattern.
0 = The LIU will NOT invert the output PRBS/QRSS pattern
1 = The LIU will invert the output PRBS/QRSS pattern
6-4
TXTEST[2:0]
R/W
000
Transmit Test Pattern [2:0]:
These bits are used to configure the Transmit T1 LIU Block to gen-
erate and transmit test patterns according to the following table.
Use of these bits automatically places the LIU section in Single Rail
mode. When this happens, the Framer section must be placed in
Single Rail mode in Reg 0x0101.
TDQRSS (Transmit/Detect Quasi-Random Signal):
QRSS pattern is a 220-1 pseudo-random bit sequence (PRBS) with
no more than 14 consecutive zeros.
TAOS (Transmit All Ones):
Whenever the user implements this configuration setting, the Trans-
mit T1 LIU Block will ignore the data that it is accepting from the
Transmit T1 Framer block (as well as the upstream system-side ter-
minal equipment) and overwrite this data with the All Ones Pattern.
TLUC (Transmit Network Loop-Up Code):
The Transmit T1 LIU Block will generate and transmit the Network
Loop-Up Code of “00001” to the line for the selected channel num-
ber n.
When Network Loop-Up code is being transmitted, the XRT86VL30
will ignore the “Automatic Loop-Code detection and Remote Loop-
Back activation” (NLCDE1 =“1”, NLCDE0 =“1” of register 0x0F03) in
order to avoid activating Remote Digital Loop-Back automatically
when the remote terminal responds to the Loop-Back request.
TLDC (Transmit Network Loop-Down Code):
The Transmit T1 LIU Block will generate and transmit the Network
Loop-Down Code of “001” to the line for the selected channel num-
ber n.
0
1
0
1
X
0
No Pattern
TDQRSS
TAOS
TLUC
Test Pattern
TLDC
TXTEST1
TXTEST0
TXTEST2