CX28344 Conexant, CX28344 Datasheet - Page 58

• Manufacturer Part Number: CX28344
• Description: (CX2834x) Dual / Triple / Quad / Hex / Octal - Enhanced DS3 / E3 Framer
• Manufacturer: Conexant

Functional Description
Table 2-1. Overhead Sourcing Methods (2 of 2)
2.1.1.1
2-12
E3-G.832
Note(s):
(1)
(2)
(3)
(4)
(5)
(6)
(7)
Mode
Either all fields enter via data stream, or only Justification Control bits (in DS3 M13/M23 and E3-G.751), or Stuff Opportunity
bits, or either justification control and stuff bits value or none.
In M12/M23 mode.
In C-bit Parity mode.
In non-SSM mode.
In SSM mode.
In either SSM or non-SSM mode.
Only one of these Overhead bits should be used at a time to enable the LAPD datalink.
FA1, FA2 (Frame)
EM (BIP-8)
TR (Trail Trace)
MA RDI
MA REI
MA PT
MA PD
MA MI
MA TM/SSM
NR (DL)
GC (DL)
(5)
(4)
(6)
Field
DS3 Mode
There are 56 Frame Overhead bits in a DS3 M-frame structure. See
details.
The External-Data source option for the DS3 mode provides the ability to insert all
the Frame Overhead bits with the data stream. When the framer operates in C-bit
parity mode there is an option to either insert all the Frame Overhead bits with the
data stream or none of them by setting bit ExtDat in the Transmit Overhead Insertion
1 Control register. When the framer operates in M13/M23 mode there are five options
(see
1.
2.
3.
4.
All Overhead bits can be inserted with the data stream by setting bit ExtDat to 1.
Only C-bits (justification control bits) enter with the data stream and the 7 Stuff
Opportunity bits are inserted via TEXT by setting bit ExtDat to 0 and ExtFEBE/
Cj-bit to 0 and ExtStf to 1.
Only 7 Stuff Opportunity bits are inserted with the data stream while Justification
Control bits are inserted from TEXT by setting bit ExtDat to 0 and ExtFEBE/Cj-
bit to 1 and ExtStf to 0.
Both C-bits (justification control bits) and the 7 Stuff Opportunity bits are
inserted with the data stream by setting bit ExtDat to 0 and ExtFEBE/Cj-bit to 0
and ExtStf to 0.
Table
2-2) concerning the insertion of Overhead bits with the data stream:
Mindspeed Technologies™
Internal-Auto
Internal-Reg
(7)
(7)
Technique
External-Data
CX28342/3/4/6/8 Data Sheet
(1)
Appendix B
28348-DSH-001-B
External-Pin
for