RS8953B/8953SPB
4.0 Registers
HDSL Channel Unit
4.4 HDSL Receive
0x60—Receive Command Register 1 (RCMD_1)
7
6
5
4
3
2
1
0
FRAMER_EN[1:0]
LOSS_SYNC[2:0]
REACH_SYNC[2:0]
REACH_SYNC[2:0] 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.
REACH_SYNC
IN_SYNC Criteria
1 frame containing SYNC
2 consecutive frames
3 consecutive frames
4 consecutive frames
5 consecutive frames
6 consecutive frames
7 consecutive frames
8 consecutive frames
000
001
010
011
100
101
110
111
LOSS_SYNC[2:0] 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.
LOSS_SYNC
OUT_OF_SYNC Criteria
1 frame not containing SYNC
2 consecutive frames
3 consecutive frames
4 consecutive frames
5 consecutive frames
6 consecutive frames
7 consecutive frames
8 consecutive frames
000
001
010
011
100
101
110
111
FRAMER_EN[1:0] 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.
FRAMER_EN
Receive Framer Search
Disabled; framer forced to OUT_OF_SYNC
SYNC_WORD_A
SYNC_WORD_B
Both SYNC_WORD_A and SYNC_WORD_B
00
01
10
11
N8953BDSB
Conexant
4-19
CONEXANT [ CONEXANT SYSTEMS, INC ]
