Chapter 3 - Using Your Wireless Modem; Phone Numbers For The Wireless Modem; Examples Of Useful At Commands - Multitech MTCBA-G-F1 User Manual

Gprs/Gsm wireless modem with RS232 interface
3. CHAPTER 3 – USING YOUR WIRELESS MODEM

Phone Numbers for the Wireless Modem

3.1.
Every wireless modem will have its own unique phone number.
•
The phone number may simply be given to you by your wireless service provider or it may be on the SIM card or
•
both. Wireless provider implementations may vary.

Examples of Useful AT Commands

3.2.
About HyperTerminal
In order to verify signal strength and roaming status, you must use a terminal application such as HyperTerminal.
To open this program in Windows XP or Windows 2003, go to Start > All Programs > Accessories >
Communications
> HyperTerminal. Other Windows operating systems have similar paths to HyperTerminal. See your system's
online
Help if you cannot find it.
A Note About AT Commands
AT commands can be used to operate, configure, and query your modem. A reference guide to the GPRS
commands is included on the Multi-Modem CD
The following two commands let you query signal strength and roaming status.
Verifying Signal Strength
Using HyperTerminal, type AT+CSQ
The modem responds with the received signal strength (rssi).
The modem responds with the received signal strength (rssi) and the channel bit error rate (ber).
RSSI ranges from 0 to 31.
Checking the Modem's Identity
Use the ATI command (Note: This command is illustrated using the capital letter i after AT)
Type ATI0 (Note: The command ends in a zero)
•
The manufacturing data displays. For example: Wavecom Modem Multiband G850 1900
Type ATI3
•
The software version displays. For example: 651_09gg...
Type ATI6
•
Displays modem data features. For example: data rates, data modes, fax classes.
Establishing a Voice Call
• Enter PIN Code (if required by your wireless provider)
Type AT+CPIN=1234
Responses: OK (PIN Code accepted)
+CME ERROR: 16 (Incorrect PIN Code)
+CME ERROR: 3 (PIN already entered [with +CMEE: 1 mode])
• Initiate a voice call
Type ATD1234; (Note: Don't forget the semicolon ";" at the end. This stands for voice calls)
Responses: OK (Communication established)
CME ERROR: 11 (PIN Code not entered [with +CMEE: 1 mode])
CME ERROR: 3 (Operation not allowed)
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