XRT72L13 Datasheet, PDF (359/370 Pages) Exar Corporation – M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC

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PRELIMINARY
XRT72L13
M13 MULTIPLEXER/CLEAR CHANNEL DS3 FRAMER IC
REV. P1.0.6
transmit the “DS2 FERF” indicator to the remote ter-
minal equipment.
M12 DS2 # 1 CONFIGURATION REGISTER (ADDRESS = 0X1A)
BIT 7
Reserved
7
R/W
0
BIT 6
Reserved
6
R/W
0
BIT 5
M12
Bypass
R/W
0
BIT 4
M12
G.747
R/W
0
BIT 3
M12
G.747 Res
R/W
X
BIT 2
M12 FERF
R/W
1
BIT 1
BIT 0
M12LBCode[1:0]
R/W
R/W
X
X
The user can terminate this forced transmission of
the “DS2 FERF” indicator by setting Bit 2 (M12 FERF)
to “0”. At this point, the M12 MUX block will set the
“X” bits, based upon “receive conditions” as detected
by M12 DEMUX block # 1.
The user can configure any of the remaining seven
(7) M12 MUX blocks to transmit a FERF condition by
also setting the Bit 2 (M12 FERF), within the corre-
sponding “M12 DS2 Configuration” Register (Address
Locations 0x1B through 0x20), to “1”.
5.2.1.1.1.2.2 Forcing the “DS1 AIS” Condition
The XRT72L13 permits the user to configure (or
force) a given M12 MUX block to transmit a DS1 AIS
signal. This can be accomplished by setting the cor-
responding bits (within the appropriate “M12 DS2
AIS” Register to “1”).
An illustration of the “M12 DS2 # 1 AIS” Register, is
presented below. This particular register permits the
user to command the M12 MUX block to overwrite
DS1 Channels 0 through 3 (e.g., the DS1 Channels
associated with M12 MUX block # 1), with a DS1 AIS
pattern..
M12 DS2 # 1 AIS REGISTER (ADDRESS = 0X21)
BIT 7
Insert
AIS
Rx DS1
Channel 3
R/W
0
BIT 6
Insert
AIS
Rx DS1
Channel 2
R/W
0
BIT 5
Insert
AIS
Rx DS1
Channel 1
R/W
0
BIT 4
Insert
AIS
Rx DS1
Channel 0
R/W
0
BIT 3
Insert
AIS
Tx DS1
Channel 3
R/W
1
BIT 2
Insert
AIS
Tx DS1
Channel 2
R/W
1
BIT 1
Insert
AIS
Tx DS1
Channel 1
R/W
1
BIT 0
Insert
AIS
Tx DS1
Channel 0
R/W
1
The XRT72L13 also contains “M12 DS2 AIS” Regis-
ters, which corresponds to the remaining M12 MUX
blocks. Each of these register also provide bit-fields
with permits the user to configure these M12 MUX
blocks to overwrite any of these DS1 channels with a
DS1 AIS pattern.
5.2.1.1.1.2.3 Forcing the DS2 AIS Pattern
M23 TX DS2 AIS REGISTER (ADDRESS = 0X08)
In addition to be able to transmit a DS1 AIS pattern,
the XRT72L13 permits the user to force the transmis-
sion of a DS2 AIS pattern.
This can be accomplished by setting the appropriate
bit-field, within the “M23 TX DS2 AIS” Register (Ad-
dress = 0x08) to “1”.
BIT 7
Not Used
R/O
0
BIT 6
TxDS2 AIS
Channel 6
R/W
0
BIT 5
TxDS2 AIS
Channel 5
R/W
0
BIT 4
TxDS2 AIS
Channel 4
R/W
0
BIT 3
TxDS2 AIS
Channel 3
R/W
0
BIT 2
TxDS2 AIS
Channel 2
R/W
0
BIT 1
TxDS2 AIS
Channel 1
R/W
0
BIT 0
TxDS2 AIS
Channel 0
R/W
0
For example, setting Bit 3 (TxDS2 AIS Channel 3),
within the “M23 Tx DS2 AIS” register, to “1” config-
ures M12 MUX Block # 4 to transmit a DS2 AIS signal
to the remote terminal equipment. Setting this partic-
ular bit-field to “0” terminates the transmission of the
DS2 AIS signal.
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