RS8953 Conexant Systems, Inc., RS8953 Datasheet - Page 59

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

RS8953B/8953SPB
HDSL Channel Unit
Figure 3-20. HDSL Auxiliary Channel Payload Timing
Figure 3-21. HDSL Auxiliary Channel Z-bit Timing
N8953BDSB
3.5.1.7 HDSL Auxiliary
TLOAD
NOTE(S):
TLOAD pulses high during auxiliary input sampling of byte1 in all payload blocks (B1-B48).
NOTE(S):
TAUX
TDAT
TLOAD
QCLK
BCLK
TAUX
TDAT
TLOAD shows transmit payload map byte1, TMAP = 11. In this case:
TAUX throughput delay varies by STUFF bit insertion, shown for illustration only.
47
Z
Sign Mag
SW
1
B47
48
Z
Transmit
SW
X1 X2 X3 X4 X5 X6 X7 X8
48
2
Z
B48
TAUX Throughput Delay
SW
3
Z
1
SW
4
B1
The HDSL auxiliary transmit channel provides an alternate source of HDSL
payload bytes and optionally, an alternate source for the last 40 Z-bits transmitted
in each HDSL frame. Auxiliary transmit data (TAUXn) is sampled by BCLKn
whenever TLOADn is active-high, as shown in
is enabled by TAUX_EN [TCMD_2; addr 0x07] and programmed in the Transmit
Payload Map Registers [TMAP; addr 0x08]. TLOADn marks specific payload
bytes selected in the TMAP registers or marks the last 40 Z-bits depending on the
setting of EXT_ZBIT [TCMD_2; addr 0x07].
SW
byte1
5
Z
2
B2
SW
6
Z
3
SW
TAUX Throughput Delay
7
B3
SW
8
Z
4
B4
SW
9
Conexant
Z
5
SW
10
B5
SW
11
Z
6
B6
SW
12
Z
7
SW
13
B7
SW
14
Z
8
B8
IND
Z
9
0
Z
9
Figures 3-20
IND
1
B9
10
Z
Z1
10
Z
B10
11
X1 X2
Z
3.0 Circuit Descriptions
11
Z
and 3-21. TLOADn
3.5 HDSL Channel
EXT_ZBIT = 0
TAUX_EN = 1
TAUX_EN = 1
EXT_ZBIT = 1
3-27