CX06833-3x/4x SMXXD Modem Data Sheet
1.4.2
MCU Firmware
MCU firmware performs processing of general modem control, command sets, data
modem, error correction and data compression (ECC), fax class 1, fax class 1.0,
voice/audio/TAM/speakerphone, worldwide, V.80, and serial DTE/parallel host interface
functions according to modem models (Table 1-1).
MCU firmware can be customized to include OEM-defined commands, i.e.,
identification codes (I3), identifier string (I4), manufacturer identification (+GMI), model
identification (+GMM), and revision identification (+GMR), as well as code
modification.
The modem firmware is provided in object code form for the OEM to program into
external ROM/flash ROM. The modem firmware may also be provided in source code
form under a source code addendum license agreement. External ROM/Flash ROM and
RAM must be installed in order to operate the modem with customized firmware.
1.4.3
Operating Modes
1.4.3.1
Data/Fax Modes
Data modem modes perform complete handshake and data rate negotiations. Using
modem modulations to optimize modem configuration for line conditions, the modem
can connect at the highest data rate that the channel can support from 56 kbps down to
2400 bps with automatic fallback.
In V.92/V.90 data modem modes (V.92 models), the modem can receive data from a
digital source using a V.92-compatible central site modem at line speeds up to 56 kbps.
With PCM upstream enabled (V.92 only), data transmission supports sending data at line
speeds up to 48 kbps. When PCM upstream is disabled, data transmission supports
sending data at line speeds up to V.34 rates. This mode can fallback to V.34 mode and to
lower rates as dictated by line conditions.
The following modes are supported in V.92 models when connected to a V.92-
compatible server supporting the feature listed.
•
Quick connect: Allows quicker subsequent connections to a server by using stored
line parameters obtained during the initial connection.
•
Modem-on-Hold: Allows detection and reporting of incoming phone calls on the
PSTN with enabled Call Waiting. If the incoming call is accepted by the user, the
user has a pre-defined amount of time of holding the data connection for a brief
conversation. The data connection resumes upon incoming call termination.
•
PCM upstream: Boosts the upstream data rates. A maximum of 48 kbps is supported
when connected to a V.92 server that supports PCM upstream.
In V.34 data modem mode (V.92 and V.34 models), the modem can operate in full-
duplex, asynchronous modes at line rates up to 33.6 kbps. Automode operation in V.34 is
provided in accordance with PN3320 and in V.32 bis in accordance with PN2330. All
tone and pattern detection functions required by the applicable ITU or Bell standards are
supported.
In V.32 bis data modem mode, the modem can operate at line speeds up to 14.4 kbps.
In fax modem mode, the modem can operate in half-duplex, synchronous modes and can
support Group 3 facsimile send and receive speeds of 14400, 12000, 9600, 7200, 4800,
and 2400 bps. Fax data transmission and reception performed by the modem are
controlled and monitored through the EIA/TIA-578 Fax Class 1, or T.31 Fax Class 1.0
1-6
Conexant
102228A
CONEXANT [ CONEXANT SYSTEMS, INC ]
