3 frames out of sync count register (foscr) – Maxim Integrated DS21Q55 User Manual
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Register Name:
PCVCR1
Register Description:
Path Code Violation Count Register 1
Register Address:
44h
Bit #
7
6
5
4
3
2
1
0
Name
PCVC15
PCVC14
PCVC13
PCVC12
PCVC11
PCVC10
PCVC9
PCVC8
Default
0
0
0
0
0
0
0
0
Bits 0 to 7/Path Code Violation Counter Bits 8 to 15 (PCVC8 to PCVC15). PCVC15 is the MSB of the 16-bit path code
violation count.
Register Name:
PCVCR2
Register Description:
Path Code Violation Count Register 2
Register Address:
45h
Bit #
7
6
5
4
3
2
1
0
Name
PCVC7
PCVC6
PCVC5
PCVC4
PCVC3
PCVC2
PCVC1
PCVC0
Default
0
0
0
0
0
0
0
0
Bits 0 to 7/Path Code Violation Counter Bits 0 to 7 (PCVC0 to PCVC7). PCVC0 is the LSB of the 16-bit path code
violation count.
13.3 Frames Out Of Sync Count Register (FOSCR)
T1 Operation
The FOSCR is used to count the number of multiframes that the receive synchronizer is out of sync. This
number is useful in ESF applications needing to measure the parameters loss of frame count (LOFC) and
ESF error events as described in AT&T publication TR54016. When the FOSCR is operated in this
mode, it is not disabled during receive loss of synchronization (RLOS = 1) conditions. The FOSCR has
alternate operating mode whereby it will count either errors in the Ft framing pattern (in the D4 mode) or
errors in the FPS framing pattern (in the ESF mode). When the FOSCR is operated in this mode, it is
disabled during receive loss of synchronization (RLOS = 1) conditions. See Table 15-4 for a detailed
description of what the FOSCR is capable of counting.
T1 FRAMES OUT OF SYNC COUNTING ARRANGEMENTS Table 15-4
FRAMING MODE
(T1RCR1.3)
COUNT MOS OR F-BIT ERRORS
(ERCNT.1)
WHAT IS COUNTED IN THE
FOSCRs
D4
MOS
Number of Multiframes Out of Sync
D4
F-Bit
Errors in the Ft Pattern
ESF
MOS
Number of Multiframes Out of Sync
ESF
F-Bit
Errors in the FPS Pattern
E1 Operation
The FOSCR counts word errors in the frame alignment signal in timeslot 0. This counter is disabled when
RLOS is high. FAS errors will not be counted when the framer is searching for FAS alignment and/or
synchronization at either the CAS or CRC4 multiframe level. Since the maximum FAS word error count
in a one-second period is 4000, this counter cannot saturate.