RS8953 Conexant Systems, Inc., RS8953 Datasheet - Page 62

• Manufacturer Part Number: RS8953
• Description: High-bit-rate Digital Subscriber Line (hdsl) Channel unit
• Manufacturer: Conexant Systems, Inc.

3.0 Circuit Descriptions
3.5 HDSL Channel
Figure 3-23. HDSL Receive Framer Synchronization
3-30
No SYNC
OUT_OF
SYNC
SYNC
No SYNC
No SYNC
Consecutive SYNC_ACQUIRED States per REACH_SYNC Criteria
Consecutive SYNC_ERRORED States per LOSS_SYNC Criteria
8
1
framer progresses through a programmable number of intermediate “Sync
Acquired” states before entering the In Sync state. In each “Sync Acquired” state,
the framer searches for the previously detected sync word value in one of two
locations based upon the absence or presence of the 4 STUFF bits. If the sync
word is detected in one of the two possible locations, the STATE_CNT counter is
incremented [STATUS_2; addr 0x06]. When STATE_CNT increments to the
value selected by the REACH_SYNC criteria [RCMD_1; addr 0x60], the framer
changes to the In Sync state. During the Sync Acquired state, if valid sync is not
detected at one of the two possible locations, the framer returns to the Out Of
Sync state, as shown in
After detecting a sync word and changing to the Sync Acquired state, the
7
2
6
3
Conexant
5
4
Figure
4
5
3-23.
3
6
2
7
1
8
SYNC
SYNC
RS8953B/8953SPB
HDSL Channel Unit
IN_SYNC
SYNC
No SYNC
N8953BDSB