REV. 1.0.1
BIT NUMBER
BIT NAME
5
J1 CRC Calculation
4
One Synchronization
Candidate Only
3
Fast Synchronization
2-0
T1 Framing Select
XRT84L38
OCTAL T1/E1/J1 FRAMER
BIT TYPE
BIT DESCRIPTION
R/W J1 CRC Calculation:
This READ/WRITE bit-field forces the framer to calculate CRC-6
bits in J1 format.In J1 format, CRC-6 calculation is done based
on the actual values of all payload bits as well as the framing
bits. In DS1 format, CRC-6 calculation is done based on the pay-
load bits only while assuming all the framing bits are one.
When this bit is set to zero:
The framer will perform CRC-6 calculation in DS1 format.
When this bit is set to one:
The framer will perform CRC-6 calculation in J1 format. This fea-
ture permits the driver to comply with J1 standard.
R/W One Synchronization Candidate Only:
This READ/WRITE bit-field forces the framing search engine of
the framer to declare synchronization while there is one and only
one candidate left.
R/W Fast Synchronization:
This READ/WRITE bit-field permits the framing search engine of
the framer to declare synchronization earlier.
R/W T1 Framing Select:
These READ/WRITE bit-fields allow the user to select one of the
five T1 framing formats supported by the framer. These framing
® formats include ESF, SLC 96, SF, N and T1DM mode.
Framing
Format
ESF
SLC®96
SF
N
T1DM
Bit 2
0
1
1
1
1
Bit 1
X
0
0
1
1
Bit 0
X
0
1
0
1
NOTE: Changing of framing format will automatically force the
framer to RESYNC.
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