Appendix A
Bt8370/8375/8376
A.6 IRSM CEPT Frame Format
Fully Integrated T1/E1 Framer and Line Interface
A.6 IRSM CEPT Frame Format
Table A-7. IRSM CEPT Frame Format Time Slot 0-Bit Allocations
SMF
Frame #
Time Slot 0 Bits 1 to 8 of Each Frame
1
2
3
4
5
6
7
8
0
1
C1/Si
0/Si
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
D
1
1
E0
1
0
E1
0
1
E16
1
1
E17
1
A
0
I
2
C2/Si
0/Si
3
A
0
D
1
E2
1
E3
0
E18
1
E19
1
4
C3/Si
1/Si
5
A
0
D
1
E4
1
E5
0
E20
1
E21
1
6
C4/Si
0/Si
7
A
0
D
1
E6
1
E7
0
E22
1
E23
1
8
C1/Si
1/Si
9
A
0
D
1
E8
1
E9
0
E24
1
E25
1
II
10
11
12
13
14
15
C2/Si
1/Si
A
0
D
1
E10
1
E11
0
E26
1
E27
1
C3/Si
E/Si
A
0
D
1
E12
1
E13
0
E28
1
E29
1
C4/Si
E/Si
A
D
E14
E15
E30
E31
Note:
1. SMF indicates the sub-multiframe. This partitioning is used in the CRC-4 calculation.
2. Si bits are International Spare Bits.
3. A bit is used to indicate a remote alarm condition (active-high).
4. Ei are per channel control bits.
5. E-bit is used to indicate a CRC-4 error. The normal state is both bits set to 1, when a CRC-4 error is detected, one of the E bits
is set to 0.
6. C1 to C4 bits are used to carry the CRC-4 code.
7. Time slot 0 that contains the 0011011 sequence is defined as the FAS word and time slot 0 that does not contain the FAS is
the Not-Word.
8. D-bits are a 4 kbps data link.
9. Bit 2 of the Not-Word is defined as the alternate framing bit.
A-10
Conexant
N8370DSE
CONEXANT [ CONEXANT SYSTEMS, INC ]
