4.0 Registers
RS8953B/8953SPB
4.16 PRA Transmit Write
HDSL Channel Unit
SA8_MODE
E_MODE
Controls the behavior of Sa8 bits, transmitted towards the HDSL link, as follows:
0 = Transparent
1 = From bits buffer 1
Controls the behavior of the E-bits transmitted towards the HDSL link, as follows:
Code
00
01
E-bits
Transparent
From bits buffer 0
Automatic
10
11
Illegal
The Automatic mode operates in conjunction with the receiver CRC4 check result (reported
also in RX_PRA_MON0), as follows:
Receiver CRC Check
E-bits Forced to
Error
OK
0
1
NOTE:
The value of this register takes effect starting with the next PCM multiframe
following the write access cycle completion.
0x71—PRA Transmit Control Register 1 (TX_PRA_CTRL1)
7
6
5
4
3
2
1
0
—
RESET_E_CNT
AIS
A_MODE
CRC4_MODE[1:0]
SYNCHR_EN
PRA_EN
PRA_EN
Enable or globally disable the receive PRA circuitry, as follows:
0 = Disable ALL RX PRA functionality
1 = Enable ALL RX PRA functionality
SYNCHR_EN
CRC4_MODE
Enable or disable the PCM multiframe synchronization state machine, as follows:
0 = Enable. Use TMSYNC input pin as a qualifier of the frame and force
synchronization state machine to HUNT mode.
1 = Disable. Use TMSYNC input as a qualifier of multiframe.
Controls the behavior of the CRC bits, transmitted towards the HDSL link, as follows:
Code
00
01
CRC4 Bits
Transparent
All ‘1’s
10
11
Re-calculated
Illegal
A_MODE
Controls the behavior of A-bits, transmitted towards the HDSL link, as follows:
0 = Transparent
1 = From bits buffer 0
4-70
Conexant
N8953BDSB