BT8375 CONEXANT [Conexant Systems, Inc], BT8375 Datasheet - Page 303

• Manufacturer Part Number: BT8375
• Description: single chip transceivers for T1/E1 and Integrated Service Digital Network (ISDN) primary rate interfaces
• Manufacturer: CONEXANT [Conexant Systems, Inc]

Bt8370/8375/8376
Fully Integrated T1/E1 Framer and Line Interface
Figure A-2. T1 Extended Superframe PCM Format
N8370DSE
FPS
Fs
or
FDL
CRC
CH
FR
1
1
1
CH
2
FR
2
2
8 Bits per Channel
A.4 Extended Superframe Format (ESF)
In Extended Superframe Format (ESF)
multiframe structure is extended to 24 frames. The channel structure is identical
to D4 (SF) format. Robbed-bit signaling is accommodated in frame 6 (A-bit),
frame 12 (B-bit), frame 18 (C-bit), and frame 24 (D-bit).
The F-bit pattern of ESF contains three functions:
1.
2.
3.
3
Framing Pattern Sequence (FPS), which defines the frame and multiframe
boundaries.
Facility Data Link (FDL), which allows data such as error performance to
be passed within the T1 link.
Cyclic Redundancy Check (CRC), which allows error performance to be
monitored and enhances the reliability of the receiver's framing algorithm.
4
CH
13
FR
13
Conexant
5
6
7
Figure
FR
23
8
A-2, and
A.4 Extended Superframe Format (ESF)
FR
Signalling Information
CH
24
A
24
B
C
24 Channels per Frame
D
ESF = 24 Frames
Table
Frame = 193 Bits
Multiframe
A-4, the
Bit 8
During:
Frame 24
Frame 18
Frame 12
Frame 6
Appendix A
A-5