RS8953B/8953SPB
4.0 Registers
HDSL Channel Unit
4.13 Receive/Transmit Status
0x06—Receive Status 2 (STATUS_2)
7
6
5
4
3
2
1
0
FEBE_OVR
CRC_OVR
CRC_ERR
SYNC_STATE[1:0]
STATE_CNT[2:0]
STATE_CNT[2:0]
Intermediate State Count—Applicable only if SYNC_STATE reports SYNC_ACQUIRED or
SYNC_ERRORED states. STATE_CNT indicates the framer’s progress through the
intermediate states.
000
001
010
011
100
101
110
111
1 Frame
2 Consecutive Frames
3 Consecutive Frames
4 Consecutive Frames
5 Consecutive Frames
6 Consecutive Frames
7 Consecutive Frames
8 Consecutive Frames
SYNC_STATE[1:0] Receive Framer Synchronization State—Reports the state of the receive framer. Refer to the
Framer Synchronization State Diagram (Figure 3-23).
00
01
10
11
OUT_OF_SYNC
SYNC_ACQUIRED
IN_SYNC
SYNC_ERRORED
When the framer enters OUT_OF_SYNC, the RFIFO is automatically reset, FEBE and
CRC error counts are suspended, and RX_ERR is activated.
When the framer reports SYNC_ACQUIRED, the RFIFO and the payload mapper are
enabled, and RX_ERR is activated.
When the framer enters IN_SYNC, the RFIFO Water Level [RFIFO_WL; addr 0xCD] is
re-established, FEBE and CRC counting resumes, and RX_ERR is activated.
When the framer reports SYNC_ERRORED, STATE_CNT indicates the number of
consecutive frames in which SYNC was not detected.
CRC_ERR
CRC Error—Shows that the CRC comparison in the previous frame resulted in a mismatch of
1 or more CRC bits. CRC_ERR is invalid in the OUT_OF_SYNC state. The MPU may copy
CRC_ERR into the first transmit IND [TIND_LO; addr 0x02] to report FEBE.
0 = CRC pass
1 = CRC error detected
CRC_OVR
FEBE_OVR
CRC Error Count Overflow—Indicates the CRC Error Count [CRC_CNT; addr 0x21] has
reached its maximum value of 255, and generates an RX_ERR interrupt.
0 = CRC error count below maximum
1 = CRC error count equals maximum 255 (0xFF)
Far-End Block Error Count Overflow—Indicates the FEBE count [FEBE_CNT; addr 0x22]
has reached its maximum value of 255. Generates an RX_ERR interrupt.
0 = FEBE count below maximum
1 = FEBE count equals maximum 255 (0xFF)
N8953BDSB
Conexant
4-57