How to Send SMS Messages Via a GSM Modem

1. Check whether your modem supports the text messaging function. Simply type 'AT+CMGF=1' and press 'Enter.' You should get 'OK' in response.
2. Insert a SIM card in your modem. The SIM card will be the number from which you'll send your SMS.
3. Type 'AT+CPIN='0000',' putting the PIN code of your SIM card---if it has any--- instead of the zeros. Press 'Enter.'
4. Put your modem in the sending SMS mode by typing 'AT+CMGF=1' and pressing 'Enter.'
5. Type 'AT+CMGS='+0000000000',' where the zeros stand fro the phone number of the SMS recipient.
6. Type the message of your SMS and press 'Ctrl' and 'Z' keys simultaneously. After a couple of seconds, the modem should reply with '+CMGS: 62,' indicating that the message was sent successfully.