XRT86VL38
PRELIMINARY
xr
OCTAL T1/E1/J1 FRAMER/LIU COMBO
REV. P1.0.6
87
3
E1
CRCSEL(1)
R/W
0
CRC Multiframe Alignment Criteria Select
These two READ/WRITE bit fields allow the user to select which
CRC-Multiframe Alignment criteria the Receive E1 Framer block will
employ. CRC Multiframe Alignment Synchronization is done by
observing whether the international bits (bit 1 of timeslot 0) of non-
FAS frames match the CRC multiframe alignment pattern
(0,0,1,0,1,1,E1,E2). The table below provides more details on the
three different CRC Multiframe Alignment Criteria.
2
E1
CRCSEL(0)
R/W
0
1
E1
CKSEQ_ENB
R/W
0
Check Sequence Enable-FAS Alignment
This READ/WRITE bit field enable or disable the frame check
sequence in FAS alignment process. By enabling the frame check
sequence, additional frame check sequence is initiated. The check
sequence consists of verifying the correct frame alignment for an
additional two frames.
0 = Setting this bit to ‘0’ will disable the Frame Check Sequence in
FAS alignment process.
1 = Setting this bit to ‘1’ will enable the Frame Check Sequence in
FAS alignment process.
T
ABLE
15: F
RAMING
S
ELECT
R
EGISTER
-E1 M
ODE
R
EGISTER
7- E1 M
ODE
F
RAMING
S
ELECT
R
EGISTER
(FSR) H
EX
A
DDRESS
: 0
X
n107
B
IT
F
UNCTION
T
YPE
D
EFAULT
D
ESCRIPTION
-O
PERATION
CRCSEL
[1:0]
CRC M
ULTIFRAME
A
LIGNMENT
C
RITERIA
S
ELECTED
00
CRC Multiframe Alignment is Disabled
01
CRC Multiframe Alignment is Enabled. Alignment is
declared if at least one valid CRC multiframe alignment
signal (0,0,1,0,1,1,E1,E2) is observed within 8ms.
10
CRC Multiframe Alignment is Enabled. Alignment is
declared if at least two valid CRC multiframe alignment
signals (0,0,1,0,1,1,E1,E2) are observed within 8ms.
11
CRC Multiframe Alignment is Enabled. Alignment is
declared if at least three valid CRC multiframe align-
ment signals (0,0,1,0,1,1,E1,E2) are observed within
8ms.