RS8953 Conexant Systems, Inc., RS8953 Datasheet - Page 87

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

RS8953B/8953SPB
HDSL Channel Unit
REACH_SYNC[2:0]
LOSS_SYNC[2:0]
FRAMER_EN[1:0]
N8953BDSB
0x60—Receive Command Register 1 (RCMD_1)
7
FRAMER_EN[1:0]
Reach Sync Framing Criteria—Contains the number of consecutive HDSL frames in which
the SYNC word is detected before the receive framer moves from the OUT_OF_SYNC to the
IN_SYNC state. REACH_SYNC determines the number of SYNC_ACQUIRED intermediate
states the framer must pass through during recovery of frame sync. ETSI standard criteria
requires two consecutive frames containing SYNC.
Loss of Sync Framing Criteria—Contains the number of consecutive HDSL frames in which
the SYNC word is not detected before the receive framer moves from the IN_SYNC to the
OUT_OF_SYNC state. LOSS_SYNC determines the number of SYNC_ERRORED
intermediate states the framer must pass through during loss of frame sync. ETSI standard
criteria requires six consecutive frames without SYNC word detected.
Receive Framer Enable—Instructs the receive framer to search for one or both of the SYNC
word patterns programmed in SYNC_WORD_A [addr 0xCB] or SYNC_WORD_B [addr
0xCC]. If enabled to search for both, then the SYNC acquisition state proceeds with only the
first detected pattern. When disabled, the framer does not count errors or generate interrupts.
6
5
LOSS_SYNC[2:0]
REACH_SYNC
LOSS_SYNC
FRAMER_EN
000
001
010
011
100
101
110
111
4
00
01
10
11
000
001
010
011
100
101
110
111
Conexant
3
Both SYNC_WORD_A and SYNC_WORD_B
Disabled; framer forced to OUT_OF_SYNC
1 frame not containing SYNC
OUT_OF_SYNC Criteria
1 frame containing SYNC
2
Receive Framer Search
2 consecutive frames
3 consecutive frames
4 consecutive frames
5 consecutive frames
6 consecutive frames
7 consecutive frames
8 consecutive frames
2 consecutive frames
3 consecutive frames
4 consecutive frames
5 consecutive frames
6 consecutive frames
7 consecutive frames
8 consecutive frames
SYNC_WORD_A
SYNC_WORD_B
IN_SYNC Criteria
REACH_SYNC[2:0]
1
4.4 HDSL Receive
4.0 Registers
0
4-19