
PEB 22554
Functional Description T1 / J1
Semiconductor Group
258
09.98
7.7.5
Additional Functions
Error performance monitoring and alarm handling
Alarm detection and generation
Alarm Indication Signal: Detection and recovery is flagged by bit FRS0.AIS and
ISR2.AIS. Transmission is enabled via bit FMR1.XAIS.
Loss of Signal: Detection and recovery is flagged by bit FRS0.LOS and ISR2.LOS.
Remote Alarm Indication: Detection and release is flagged by bit FRS0.RRA and
ISR2.RA/RAR. Transmission is enabled via bit FMR4.XRA.
Excessive Zeros: Detection is flagged by bit FRS1.EXZD.
Pulse Density Violation: Detection is flagged by bit FRS1.PDEN and ISR0.PDEN.
Transmit Line Shorted: Detection and release is flagged by bit FRS1.XLS and
ISR1.XLSC.
Transmit Ones Density: Detection and release is flagged by bit FRS1.XLO and
ISR1.XLSC.
Table 27
Summary of Alarm Detection and Release
Alarm
Red Alarm or
Loss of Signal
(LOS)
Detection Condition
no transitions (logical zeros) in a
programmable time interval of 16
- 4096 consecutive pulse
periods. Programmable receive
input signal threshold
Clear Condition
programmable number of ones
(1-256) in a programmble time
interval of 16 - 4096 consecutive
pulse periods. A one is a signal
with a level above the
programmed threshold.
or
the pulse density is fulfilled and
no more than 15 contiguous
zeros during the recovery
interval are detected.
active for at least one multiframe.
FMR4.AIS3 = 0:
more than 2 zeros in 12 or 24
frames (ESF),
Blue Alarm or
Alarm Indication
Signal (AIS)
FMR4.AIS3 = 0:
less than 3 zeros in 12 frames or
24 frames (ESF),
FMR4.AIS3 = 1:
less than 4 zeros in 12 frames or
less than 6 zeros in 24 frames
(ESF)
FMR4.AIS3 = 1:
more than 3 zeros in 12 frames
or more than 5 zeros in 24
frames (ESF)