DS2154
5.4 FAS Error Counter
FAS Count Register 1 (FASCR1) is the most significant word and FASCR2 is the least significant word
of a 12-bit counter that records word errors in the Frame Alignment Signal in timeslot 0. This counter is
disabled during loss of synchronization conditions, (RLOS = 1). Since the maximum FAS word error
count in a 1-second period is 4000, this counter cannot saturate.
FASCR1: FAS BIT COUNT REGISTER 1 (Address=02 Hex)
FASCR2: FAS BIT COUNT REGISTER 2 (Address=04 Hex)
(MSB)
(LSB)
FAS11
FAS10
FAS4
FAS9
FAS3
FAS8
FAS2
FAS7
FAS1
FAS6
FAS0
(note 2)
(note 1)
(note 2) FASCR1
FAS5
(note 1) FASCR2
SYMBOL
FAS11
POSITION NAME AND DESCRIPTION
FASCR1.7
FASCR2.2
MSB of the 12-bit FAS error count.
LSB of the 12-bit FAS error count.
FAS0
NOTES:
1. The lower 2 bits of FASCR1 at address 02 are the most significant bits of the 10-bit CRC4 error
counter.
2. The lower 2 bits of FASCR2 at address 04 are the most significant bits of the 10-bit E-bit counter.
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