RS8953 Conexant Systems, Inc., RS8953 Datasheet - Page 30

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

2.0 Pin Descriptions
2.2 Signal Definitions
Table 2-2. Signal Definitions (2 of 4)
2-8
TLOAD2
TLOAD3
RAUX2
RAUX3
BCLK2
BCLK3
QCLK2
QCLK3
TAUX2
TAUX3
RDAT2
RDAT3
TDAT2
TDAT3
TLOAD1
ROH2
ROH3
RAUX1
Signal
BCLK1
QCLK1
RDAT1
TDAT1
TAUX1
ROH1
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
(3)
Receive Overhead
Quaternary Clock
Receive Auxiliary
Transmit Load
Transmit Data
Auxiliary Data
Receive Data
Bit Clock
Transmit
Indicator
Indicator
Name
Data
I/O
I
I
I
I
(1)
(1)
O
(1)
(1)
O
O
O
Corresponds to three HDSL and three Auxiliary channels. BCLKn operates at
twice the 2B1Q symbol rate. The rising edge of BCLKn outputs TDATn, TLOADn,
RAUXn and ROHn; the falling edge samples QCLKn, RDATn, and TAUXn inputs.
Operates at the 2B1Q symbol rate (half-bit rate) and identifies sign and
magnitude alignment of both RDATn and TDATn serially encoded bit streams.
The falling edge of BCLKn samples QCLKn: 0 = sign bit; 1 = magnitude bit.
HDSL transmit data output at the bit rate on the rising edge of BCLKn. Serially
encoded with the 2B1Q sign bit aligned to the QCLKn low level and the 2B1Q
magnitude bit aligned to the QCLKn high level.
HDSL transmit auxiliary data input sampled on the falling edge of BCLKn when
TLOADn is active. TAUXn replaces data normally supplied by PCM or HDSL
transmitters to the HDSL scrambler input. Payload bytes or Z-bits can be
mapped from TAUXn.
HDSL receive data input sampled on the falling edge of BCLKn. The serially
encoded 2B1Q sign bit is sampled when QCLKn is low, and the 2B1Q magnitude
bit is sampled when QCLKn is high.
Receives data from the HDSL descrambler output on the rising edge of BCLKn.
Includes all SYNC, STUFF, HOH, payload, and Z-bits. RAUXn shares pin locations
with DROP, INSERT, and MSYNC, as controlled by RAUX_EN (CMD_6; addr
0xF3).
Active-high output that indicates when specific payload or Z-bits are sampled at
TAUXn. TLOADn is active for 8 bits coincident with each marked payload byte or
1 bit for Z-bits. The last 40 Z-bits or any combination of payload bytes may be
marked.
Indicate when overhead is received. Has two modes of operation:
• RAS = 0. ROHn is high to mark only data passed into the RFIFO.
• RAS=1. ROHn is high to mark only the last 40 Z-bits.
HDSL Channels
Conexant
Description
RS8953B/8953SPB
HDSL Channel Unit
N8953BDSB