cx20493-35/app Conexant Systems, Inc., cx20493-35/app Datasheet - Page 28

• Manufacturer Part Number: cx20493-35/app
• Description: With Cx20493 Smartdaa?
• Manufacturer: Conexant Systems, Inc.

2.7.3
2.8
2.9
2.10
2.10.1
2.10.2
2-8
CX81801-7x/8x SmartV.XX Modem in 128-Pin LQFP with CX20493 in 32-Pin LQFP Data Sheet
Remote Hangup Detection
Fax Class 1 and Fax Class 1.0 Operation
Point-of-Sales Support
Voice/Audio Mode
Online Voice Command Mode
Voice Receive Mode
The Remote Hangup Detection feature will cause the modem to go back on-hook and
respond with the message “LINE REVERSAL DETECTED” during a data connection
when the remote modem is disconnected for abnormal termination reasons (remote phone
line unplugged, remote server/modem shutdown). For Voice applications, this method
can be used in addition to silence detection to determine when a remote caller has hung
up to terminate a voice recording.
Facsimile functions operate in response to fax class 1 commands when +FCLASS=1 or to
fax class 1.0 commands when +FCLASS=1.0.
In the fax mode, the on-line behavior of the modem is different from the data (non-fax)
mode. After dialing, modem operation is controlled by fax commands. Some AT
commands are still valid but may operate differently than in data modem mode.
Calling tone is generated in accordance with T.30.
Point-of-Sales (POS) terminals usually need to exchange a small amount of data in the
shortest amount of time. Low speed modulations such as Bell212A or V.22 are still
mainly used in POS applications. Additionally, new non-standard sequences have been
developed to better support POS applications.
Industry standard and shortened answer tone B103 and V.21 are supported, as well as
FastPOS (V.29) and V.22 Fast Connect. POS terminal modulations are supported by the
$F command.
Voice and audio functions are supported by the Voice Mode. Voice Mode includes four
submodes: Online Voice Command Mode, Voice Receive Mode, Voice Transmit Mode
and Full-Duplex Receive and Transmit Mode.
This mode results from the connection to the telephone line or a voice/audio I/O device
(e.g., microphone, speaker, or handset) through the use of the +FCLASS=8 and +VLS
commands. After mode entry, AT commands can be entered without aborting the
connection.
This mode is entered when the +VRX command is active in order to record voice or
audio data input at the RIN pin, typically from a microphone/handset or the telephone
line.
Received analog voice samples are converted to digital form and compressed for reading
by the host. AT commands control the codec bits-per-sample rate.
Conexant
102247B