Modem Commands - Lenovo ThinkPad T420 User Manual

Industry standard fax support up to 14.4 Kbps:
Fax protocols
• V.21 Ch 2 (300-bps fax)
• V.17 (up to 14.4-Kbps fax)
• V.29 (9600-bps fax)
• V.27ter (4800-bps fax)
Computer telephony function support:
• DTMF and pulse dialing
• Detecting DTMF digits received from the phone line
• Call progress monitoring
• An auto-dialing feature
• Telephony API (TAPI)

Modem commands

This section provides information on the AT modem commands, in case you need to operate your modem
from terminal software.
Running commands
Your modem is in command mode at power-on and is ready to receive and run AT commands. It remains in
command mode until it connects with a remote modem. You can send commands to the modem from an
attached terminal or a PC running a communication program.
The modem is designed to operate at common DTE speeds ranging from 115.2 Kbps (or 57.6 Kbps) to 300
Kbps. All commands and data must be issued to the modem at one of the valid DTE speeds.
Command format
All commands except A/ A/ A/ must begin with the prefix AT, followed by the command letter, and must end with
the Enter key. Spaces are allowed in the command string to increase readability, but the modem ignores
them while executing a command. All commands may be typed in either uppercase or lowercase, but not in
mixed case. A command issued without a parameter is considered to have parameter "0".
Examples: A A A TL[Ent TL[Ent TL[Ent er] er] er]
This command causes your modem to lower the volume from its speaker.
Refer to the following tables of AT commands and extended AT commands.
Table 3. Modem command list
Command Description
Z Z Z
Reset to default
configuration
Syntax
Z Z Z
Values
.
Chapter 2 Using your computer
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