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XRT83SH38
54
REV. 1.0.7
8-CHANNEL T1/E1/J1 SHORT-HAUL LINE INTERFACE UNIT
TABLE 23: EQUALIZER CONTROL AND TRANSMIT LINE BUILD OUT
EQC[4:0]
T1/E1 MODE/RECEIVE SENSITIVITY
TRANSMIT LBO
CABLE
CODING
0x08h
T1 Short Haul/15dB
0 to 133 feet (0.6dB)
100
TP
B8ZS
0x09h
T1 Short Haul/15dB
133 to 266 feet (1.2dB)
100
TP
B8ZS
0x0Ah
T1 Short Haul/15dB
266 to 399 feet (1.8dB)
100
TP
B8ZS
0x0Bh
T1 Short Haul/15dB
399 to 533 feet (2.4dB)
100
TP
B8ZS
0x0Ch
T1 Short Haul/15dB
533 to 655 feet (3.0dB)
100
TP
B8ZS
0x0Dh
T1 Short Haul/15dB
Arbitrary Pulse
100
TP
B8ZS
0x1Ch
E1 Short Haul/15dB
ITU G.703
75
Coax
HDB3
0x1Dh
E1 Short Haul/15dB
ITU G.703
120
TP
HDB3
TABLE 24: MICROPROCESSOR REGISTER 0X01H BIT DESCRIPTION
CHANNEL 0-7 (0X01H-0X71H)
BIT
NAME
FUNCTION
Register
Type
Default
Value
(HW reset)
D7
RxTSEL
Receive Termination Select
Upon power up, the receiver is in "High" impedance. RxTSEL is
used to switch between the internal termination and "High" imped-
ance.
0 = "High" Impedance
1 = Internal Termination
R/W
0
D6
TxTSEL
Transmit Termination Select
Upon power up, the transmitter is in "High" impedance. TxTSEL is
used to switch between the internal termination and "High" imped-
ance.
0 = "High" Impedance
1 = Internal Termination
R/W
0
D5
D4
TERSEL1
TERSEL0
Receive Line Impedance Select
TERSEL[1:0] are used to select the line impedance for T1/J1/E1.
00 = 100
01 = 110
10 = 75
11 = 120
R/W
0
D[3:2]
JASEL[1:0] Jitter Attenuator Select
JASEL[1:0] are used to select the jitter attenuator in the transmit or
receive path.
00 = Disabled
01 = Transmit Path
10 = Receive Path
11 = Receive Path
R/W
0