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Data Sheet
149
Rev. 1.2, 2006-01-26
QuadFALC
TM
PEF 22554 E
Functional Description E1
AIS in time slot 16: Detection and release is flagged by bit FRS1.TS16AIS and ISR3.AIS16. Transmission is
enabled by writing all ones in registers XS(16:1).
LOS in time slot 16: Detection and release is flagged by bit FRS1.TS16LOS. Transmission is enabled by
writing all zeros in registers XS(16:1)
Remote Alarm in time slot 16: Detection and release is flagged by bit FRS1.TS16RA and ISR3.RA16.
Transmission is enabled by bit XS1.2
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 40
Summary of Alarm Detection and Release (E1)
Alarm
Detection Condition
Clear Condition
Loss-Of-Signal
(LOS)
No transitions (logical zeros) in a
programmable time interval of 16 to
4096 consecutive pulse periods.
Programmable receive input signal
threshold
Programmable number of ones (1 to 256) in
a programmable time interval of 16 to 4096
consecutive pulse periods. A one is a signal
with a level above the programmed
threshold.
Alarm Indication Signal (AIS) FMR0.ALM = 0:
Less than 3 zeros in
250
s and loss of frame alignment
declared.
FMR0.ALM = 1:
Less than 3 zeros in
Each of two consecutive 250
s
periods
FMR0.ALM = 0:
More than 2 zeros in 250
s.
FMR0.ALM = 1:
More than 2 zeros in each of two
500
s periods
Remote Defect Indication
"alarm indication to the remote" bit is
binary ONE (1) for z consecutive
CAS multiframe periods, where z = 1
...5. z is not provisionable.
"Remote alarm indication" bit is
binary ONE (1) for z consecutive
double frame periods, where z =
2,...5. z is not provisionable.
"alarm indication to the remote end" bit is
binary ZERO (0) for z consecutive CAS
multiframe periods.
"Remote alarm indication" bit is binary
ZERO (0) for z consecutive double frame
periods.
Severely Errored Frames
(SEF) Indication
Two or more frame bit errors in the
timing window are detected.
Signal is in-frame and there are less than
two frame bit errors in the timing window
Remote Alarm
(RRA)
Bit 3 = 1 in time slot 0 not containing
the FAS word
Set conditions no longer detected.
Remote Alarm in
time slot 16 (TS16RA)
Y-bit = 1 received in CAS multiframe
alignment word
Y-bit = 0 received in CAS multiframe
alignment word
Loss-of-Signal in
time slot 16
(TS16LOS)
All zeros for at least 16
consecutively received time slots 16
Receiving a one in
time slot 16
Alarm Indication Signal in
time slot 16 (TS16AIS)
Time slot 16 containing less than 4
zeros in each of two consecutive
CAS multiframes periods
Time slot 16 containing more than 3 zeros in
one CAS multiframe
Transmit Line Short
(XLS)
More than 3 pulse periods with
highly increased transmit line
current on XL1/2
Transmit line current limiter inactive, see
Transmit Ones-Density
(XLO)
32 consecutive zeros in the transmit
data stream on XL1/2
Cleared with each transmitted pulse