Chapter 3 – Using Your Wireless Modem
Multi-Tech Systems, Inc. MultiModem GPRS USB Wireless Modem User Guide 25
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.
Signal Strength Verification – RSSI
21 – 31 Exceptional
11 - 20 Average
0 - 10 Weak or Insufficient
99 No signal
BER ranges from 0 to 7 (Seven is the highest error rate).
Checking Network Registration and Roaming Status
In this procedure, you will verify that the Wireless MultiModem has been registered on the wireless network.
Using HyperTerminal, type AT+CREG?
The modem will respond in one of the following ways:
Network Registration Verification
Value Network Registration Status
0,0 The modem is not registered on any network
0,1 The modem is registered on the home network
0,5 The modem is registered on a network and it is roaming
Note: If the modem indicates that it is not registered, verify the signal strength to determine if the problem
is the strength of the received signal.
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)
• Initiate an emergency call
Type ATD112; (Note: Don’t forget the semicolon “;” at the end. This stands for voice calls)
Responses: OK
• Hang up
Type ATH
Responses: OK