RS8953 Conexant Systems, Inc., RS8953 Datasheet - Page 108

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

4.0 Registers
4.10 Data Path Options
DBANK_3[7:0]
FILL_PATT[7:0]
TSTUFF[3:0]
4-40
0xDE—Data Bank Pattern 3 (DBANK_3)
0xEA—Fill Pattern (FILL_PATT)
0xE4—Transmit Stuff Bit Value (TSTUFF)
—
7
7
7
Data Bank Pattern 3—Holds a third possible 8-bit pattern for transmit or receive insertion. See
DBANK_1 above. If RSIG_EN = 1 [CMD_6; addr 0xF3], DBANK_3 is a receive signaling
buffer and is not available as an alternate source for receive PCM timeslots. If TAUX_EN = 1
[TCMD_2; addr 0x07], DBANK_3 is a transmit auxiliary channel data buffer and is not
available for insertion into transmit HDSL payload bytes but remains available for insertion
into RSER timeslots.
Fill Pattern—When PRBS_DIS [CMD_3; addr 0xE7] is set, FILL_PATT replaces the PRBS
generator output with its 8-bit programmable pattern. The transmit Routing Table
[ROUTE_TBL; addr 0xED] may then select FILL_PATT as a fourth possible data bank to fill
idle or unpopulated PCM timeslots and HDSL payload bytes. In this case, FILL_PATT also
establishes an 8-bit pattern checked by the receiver’s BER meter when enabled [BER_EN in
COMBINE_TBL; addr 0xEE].
significant byte of the PRBS generator’s LFSR. In this case, FILL_PATT must be initialized to
any non-zero value before the MPU issues the PRBS_RST command.
Transmit Stuffing Bits—Contains the 4-bit STUFF value used by all HDSL transmitters when
any HDSL output frame contains bit stuffing. TSTUFF[0] is the sign bit and first bit of the
first quat transmitted during STUFF words.
—
The following configuration can cause the HDSL frame to become corrupted:
DBank_1, DBank_2, or DBank_3 is the source of data for HDSL payload byte 33.
DBank_2 is the source of data for HDSL payload byte 0.
The LSB of the DBank_2 pattern is equal to one (1).
The following configuration can cause the HDSL frame to become corrupted:
DBank_1, DBank_2, or DBank_3 is the source of data for HDSL payload byte 33.
DBank_3 is the source of data for HDSL payload byte 0.
The LSB or the DBank_3 pattern is equal to one (1).
When PRBS_DIS is zero (PRBS enabled), FILL_PATT is used to initialize the least
6
6
6
—
5
5
5
—
4
4
4
Conexant
FILL_PATT[7:0]
DBANK_3[7:0]
MAG1
3
3
3
SIGN1
2
2
2
TSTUFF[3:0]
MAG0
RS8953B/8953SPB
1
1
1
HDSL Channel Unit
N8953BDSB
SIGNO
0
0
0