Agere Systems DSP1648C
Host-Based Controller V.92 Modem Chip Set
Product Brief
September 2001
Video-Ready Interface
Functional Description
The video-ready interface supplied by the DSP1648C
chip set provides video conferencing capability using
traditional POTS lines. The implementation of the
ITU-T V.80 standard provides a seamless interface for
either software or hardware-accelerated ITU-T H.324
implementation. The host-based architecture of this
chip set facilitates future upgrades.
DSP1648C
The Agere Systems DSP1648C chip set is a two-chip
solution consisting of Agere Systems DSP1648C
digital signal processor, a CSP1035A silicon data
access arrangement (DAA) or a CSP1034 line codec.
An optional CSP1027 audio codec is required to sup-
port full-duplex speakerphone. It supports V.92, V.90,
V.34 data, and FAX rates up to 14.4 kbits/s. The host-
based controller solution is compatible with Windows
95 and Windows 98 telephony application program
interface (TAPI), including the unimodem and unimo-
dem-V service providers, and can be used with off-the-
shelf TAPI compliant voice and telephony applications.
Telephone Answering Machine
The TAM mode uses a modified version of the com-
mand set defined by ITU-T recommendation V.253. All
AT commands are sent through the COM port. The
actual voice samples are sent by a WAVE driver
directly to the data pump hardware.
In order to be backward compatible to some voice
applications, the DSP1648C also supports a standard
V.253 command set. In V.253 voice commands, voice
samples are sent to the COM port along with <DLE>
shielded commands.
The DSP1648C chip set supports ITU-T V.253 based
TAM features, using DLE shielded commands and
AT+V commands supporting 7.2 kHz, 8.0 kHz, and
11.025 kHz for both 8-bit and 16-bit samples.
Concurrent data, FAX, voice discrimination, and DTMF
tone detection are supported during TAM mode. Dis-
tinctive ring and synthesized rings are available in TAM
mode.
AGERE SYSTEMS
DSP1648C HOST-BASED CONTROLLER MODEM CHIP
ROM CODED
DSP1648C
LINE CODEC
HOST
PROCESSOR
TELEPHONE
LINE
CSP1034C
DAA
PCI
100-PIN
TQFP
48-PIN TQFP
MICROPHONE
AUDIO
CODEC
AUDIO
CIRCUITRY
CSP1027
48-PIN TQFP
SPEAKER
OPTIONAL FOR DSP-BASED FDSP
5-6393 (F) n
Figure 1. Agere Systems DSP1648C and Transformer-Based DAA Block Diagram
with Audio Codec
2
Agere Systems Inc.
AGERE [ AGERE SYSTEMS ]
