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XRT83VSH38
63
8-CHANNEL T1/E1/J1 SHORT-HAUL LINE INTERFACE UNIT
REV. 1.1.0
TABLE 38: MICROPROCESSOR REGISTER 0X81H, BIT DESCRIPTION
REGISTER ADDRESS
0X81H
NAME
FUNCTION
REGISTER
TYPE
RESET
VALUE
BIT #
D7
LCV_OF
Line Code Violation / Over Flow Select
0 = LCV_OFD monitors LCV activity
1 = LCV_OFD monitors OF activity
R/W
0
D6
CLKSEL2
Clock Select Inputs for Master Clock Synthesizer bit 2:
In Host mode, CLKSEL[2:0] are input signals to a programma-
ble frequency synthesizer that can be used to generate a mas-
ter clock from an external accurate clock source according to
the following table;
In Hardware mode, the state of these signals are ignored and
the master frequency PLL is controlled by the corresponding
Hardware pins.
R/W
0
D5
CLKSEL1
Clock Select inputs for Master Clock Synthesizer bit 1:
See description of bit D6 for function of this bit.
R/W
0
D4
CLKSEL0
Clock Select inputs for Master Clock Synthesizer bit 0:
See description of bit D6 for function of this bit.
R/W
0
D3
MCLKRATE
Master clock Rate Select: The state of this bit programs the
Master Clock Synthesizer to generate the T1/J1 or E1 clock.
The Master Clock Synthesizer will generate the E1 clock when
MCLKRATE = “0”, and the T1/J1 clock when MCLKRATE =
“1”.
R/W
0
D2
RXMUTE
Receive Output Mute: Writing a “1” to this bit, mutes receive
outputs at RPOS/RDATA and RNEG/LCV pins to a “0” state for
any channel that detects an RLOS condition.
NOTE: RCLK is not muted.
R/W
0
D1
EXLOS
Extended LOS: Writing a “1” to this bit extends the number of
zeros at the receive input of each channel before RLOS is
declared to 4096 bits. Writing a “0” reverts to the normal mode
(175+75 bits for T1 and 32 bits for E1).
R/W
0
D0
ICT
In-Circuit-Testing: Writing a “1” to this bit configures all the
output pins of the chip in high impedance mode for In-Circuit-
Testing. Setting the ICT bit to “1” is equivalent to connecting
the Hardware ICT pin 88 to ground.
R/W
0
2048
1544
MCLKE1
kHz
2048
1544
MCLKT1
kHz
1544
2048
1544
2048
CLKOUT/
kHz
1544
2048
1544
0
1
CLKSEL0
0
CLKSEL1
0
CLKSEL2
0
1
0
1544
2048
0
1
0
1
MCLKRATE
1
0