4.0 Registers
RS8953B/8953SPB
4.13 Receive/Transmit Status
HDSL Channel Unit
SYNC_AB
SYNC_WORD_A or SYNC_WORD_B Acquired—Reports which one of the two
programmed SYNC words is detected by the receive framer. Updated each time the receive
framer state transitions from OUT_OF_SYNC to SYNC_ACQUIRED.
0 = SYNC_ACQUIRED with SYNC_WORD_A
1 = SYNC_ACQUIRED with SYNC_WORD_B
TR_INVERT
Tip/Ring Inversion—Indicates the receive framer acquired an inverted SYNC word A or B,
indicating that the receive tip and ring wire pair connections are reversed. The RS8953B
automatically inverts the sign bits of all received data as it is presented on the RDATn input
when inversion is detected. TR_INVERT is updated each time the receive framer state
transitions from OUT_OF_SYNC to SYNC_ACQUIRED.
0 = SYNC_ACQUIRED with expected SYNC word
1 = SYNC_ACQUIRED with inverted SYNC word
RX_STUFF
Receive STUFF—Indicates whether the receive framer detected 4 STUFF bits or no STUFF
bits in the previous frame.
0 = No STUFF bits detected
1 = 4 STUFF bits detected
RFIFO_FULL
Receive FIFO Full Error—Indicates the RFIFO has overflowed. Also reported in
ERR_STATUS and IRR (if RX_ERR_EN in RCMD_2[addr0x61]), and generates an
RX_ERR interrupt (if RX_ERR in IMR is enabled). RFIFO_FULL is indicative of clock
problems and may be triggered by DPLL acquisition, DPLL switchover, or by changes to the
receive combination table, or to the receive payload map.
0 = RFIFO normal
1 = RFIFO overflowed
RFIFO_MPTY
RFIFO_SLIP
Receive FIFO Empty Error—Indicates the RFIFO has Underrun. Also reported in
ERR_STATUS and IRR (if RX_ERR_EN in RCMD_2[addr0x61]), and generates an
RX_ERR interrupt (if RX_ERR in IMR is enabled). RFIFO_MPTY is indicative of clock
problems and may be triggered by events similar to those which cause RFIFO_FULL errors.
0 = RFIFO normal
1 = RFIFO Underrun
Receive FIFO Slip—Indicates the number of payload bytes mapped into the RFIFO is not
equal to the number of PCM timeslots mapped out of the RFIFO over a 6 ms period, also
reported in ERR_STATUS and IRR (if RX_ERR_EN in RCMD_2[addr0x61]). It generates an
RX_ERR interrupt (if RX_ERR in IMR is enabled). RFIFO_SLIP errors are caused by a
receive framer OUT_OF_SYNC condition, or by improper configuration of the receive
payload map, or the receive combination table.
0 = RFIFO normal
1 = RFIFO unbalanced
MAJOR_VER[1:0] Major Version Number—Contains the device major revision level which the CPU can read to
determine the installed device, enable new software features, and remove unnecessary software
corrections from older versions.
Bt8953
01
01
Bt8953A
RS8953B
CH1 (address 0x05)
CH2 (address 0x0D)
CH3 (address 0x15)
01
01
10
01
01
11
01
4-56
Conexant
N8953BDSB