Somerdata R2D3-ASSY-0130, Установка и эксплуатация

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R
2
D
3
Data Capture Card
Installation and Operation 5-6
G.704 Framed Data Structure
All versions of the card synchronise to framed E1/PRI
(ITU-T G.703/G.704) input signals with the following data
structure.
The bitstream should consist of 32 byte frames containing a
Frame Alignment Synchronising Byte (FAS) in every other
frame with an appropriate alternate (NFAS) Byte in other
frames.
A sequence of correct FAS/NFAS/FAS (three frames) is
required to ensure synchronisation is achieved.
Loss of synchronisation will be indicated when this sequence
is not present.
To ensure correct operation, the signal should be present
before recording commences.
Sequence of
transmission
TS
0
TS
1
TS
2
TS
3
TS
4
TS
5
TS
6
TS
7
TS
8
TS
9
TS
1
0
TS
1
1
TS
1
2
TS
1
3
TS
1
4
TS
1
5
TS
1
6
TS
1
7
TS
1
8
TS
1
9
TS
2
0
TS
2
1
TS
2
2
TS
2
3
TS
2
4
TS
2
5
TS
2
6
TS
2
7
TS
2
8
TS
2
9
TS
3
0
TS
3
1
8 bits
X 0 0 1 1 0 1 1
Alternate frames X = don't care
X 1 0 X X X X X
Frame
Alignment
Word
1 Frame - 256 bits - 2,048 kbits/s
TS 0