
XRT84L38
351
REV. 1.0.1
OCTAL T1/E1/J1 FRAMER
If Loss of Signal condition is present in the incoming DS1 frame, the XRT84L38 framer can generate a Receive
Loss of Signal interrupt associated with the setting of Receive Loss of Signal bit of the Alarm and Error Status
Register to one.
To enable the Receive Loss of Signal interrupt, the Receive Loss of Signal Interrupt Enable bit of the Alarm and
Error Interrupt Enable Register (AEIER) has to be set to one. In addition, the Alarm and Error Interrupt Enable
bit of the Block Interrupt Enable Register (BIER) needs to be one.
The table below shows configurations of the Receive Loss of Signal Interrupt Enable bit of the Alarm and Error
Interrupt Enable Register (AEIER).
ALARM AND ERROR INTERRUPT ENABLE REGISTER (AEIER) (INDIRECT ADDRESS = 0XNAH, 0X03H)
The table below shows configurations of the Alarm and Error Interrupt Enable bit of the Block Interrupt Enable
Register.
BLOCK INTERRUPT ENABLE REGISTER (BIER) (INDIRECT ADDRESS = 0XNAH, 0X01H)
When these interrupt enable bits are set and one or more Loss of Signals are present in the incoming DS1
frame, the XRT84L38 framer will declare Receive Loss of Signal by doing the following:
Set the Receive Loss of Signal bit of the Alarm and Error Status Register to one indicating there is one or
more Loss of Signals. This status indicator is valid until the Framer Interrupt Status Register is read.
Reading this register clears the associated interrupt if Reset-Upon-Read is selected in Interrupt Control
Register (ICR). Otherwise, a write-to-clear operation by the microprocessor is required to reset these status
indicators.
The table below shows the Receive Loss of Signal status bits of the Alarm and Error Status Register.
ALARM AND ERROR STATUS REGISTER (AESR) (INDIRECT ADDRESS = 0XNAH, 0X02H)
B
IT
N
UMBER
B
IT
N
AME
B
IT
T
YPE
B
IT
D
ESCRIPTION
4
Receive Loss of
Signal Interrupt
Enable
R/W
0 - The Receive Loss of Signal interrupt is disabled. Occurrence of Loss of
Signals will not generate an interrupt.
1 - The Receive Loss of Signal interrupt is enabled. Occurrence of Loss of
Signals will generate an interrupt.
B
IT
N
UMBER
B
IT
N
AME
B
IT
T
YPE
B
IT
D
ESCRIPTION
1
Alarm and Error
Interrupt Enable
R/W
0 - Every interrupt generated by the Alarm and Error Interrupt Status Reg-
ister (AEISR) is disabled.
1 - Every interrupt generated by the Alarm and Error Interrupt Status Reg-
ister (AEISR) is enabled.
B
IT
N
UMBER
B
IT
N
AME
B
IT
T
YPE
B
IT
D
ESCRIPTION
4
Receive Loss of
Signal State
RUR /
WC
0 - There is no change of Loss of Signal state in the incoming DS1 payload
data.
1 - There is change of Loss of Signal state in the incoming DS1 payload
data.