XRT84L38IB Exar Corporation, XRT84L38IB Datasheet - Page 409

• Manufacturer Part Number: XRT84L38IB
• Description: Network Controller & Processor ICs 8 Ch T1/E1 Framer
• Manufacturer: Exar Corporation

Specifications of XRT84L38IB

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

REV. 1.0.1
The table below shows configurations of the Receive Bipolar Violation Interrupt Enable bit of the Alarm and
Error Interrupt Enable Register (AEIER).
ALARM AND ERROR INTERRUPT ENABLE REGISTER (AEIER)
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 Bipolar Violations are present in the incoming E1
frame, the XRT84L38 framer will declare Receive Bipolar Violation by doing the following:
•
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 Bipolar Violation status bits of the Alarm and Error Status Register.
ALARM AND ERROR STATUS REGISTER (AESR) (INDIRECT ADDRESS = 0XNAH, 0X02H)
12.5.6
A Loss of Signal or LOS occurs when neither RPOS nor RNEG inputs of the framer receives a high level input
for 32 consecutive bit times. The Alarm indication logic within the Receive Framer block of the XRT84L38
framer monitors the incoming E1 frames for Loss of Signal conditions. If used in conjunction with EXAR LIUs,
for example, the XRT83L3x family, the XRT84L38 framer also declares LOS when the Receive LOS (RxLOS)
input pin is pulled HIGH.
The removal of LOS condition is through detection of 12.5% ones over 32 consecutive bits. In the other words,
XRT84L38 framer will remove LOS alarm when there is no 4 consecutive zeros received.
N
OTE
N
N
N
Set the Receive Bipolar Violation bit of the Alarm and Error Status Register to one indicating there are one or
more Bipolar Violations. This status indicator is valid until the Framer Interrupt Status Register is read.
UMBER
UMBER
UMBER
B
B
B
3
1
3
: The implementation of LOS detection and removal only apply to B8ZS coded bipolar inputs.
IT
IT
IT
How to configure the framer to detect Loss of Signal
Violation Interrupt
Alarm and Error
Interrupt Enable
Receive Bipolar
Receive Bipolar
Violation State
B
B
B
Change
Enable
IT
IT
IT
N
N
N
AME
AME
AME
B
B
B
RUR /
IT
IT
IT
R/W
R/W
WC
T
T
T
YPE
YPE
YPE
0 - The Receive Bipolar Violation interrupt is disabled. Occurrence of one
or more bipolar violations will not generate an interrupt.
1 - The Receive Bipolar Violation interrupt is enabled. Occurrence of one
or more bipolar violations will generate an interrupt.
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.
0 - There is no change of Bipolar Violation state in the incoming E1 pay-
load data.
1 - There is change of Bipolar Violation state in the incoming E1 payload
data.
389
B
B
B
IT
IT
IT
D
D
D
ESCRIPTION
ESCRIPTION
ESCRIPTION
(INDIRECT ADDRESS = 0XNAH,
OCTAL T1/E1/J1 FRAMER
XRT84L38