How to make a call using AT commands

1. Command -> ATD123456789;
2. Press Enter
3. Modem returns <- OK

To end the call -
1. command -> ATH
2. Press Enter

SENDING SMS USING AT

AT commands: "AT" meaning attention
AT commands are means of communication between processor and modem.This is the only language any modem can understand. Following are the usage of AT commands -

1. Sending SMS Messages from a Computer GSM/GPRS Modem

Command -> AT                                          // to check the modem is alive
Reply   <- OK                                             // modem send ok to say I am alive
Command -> AT+CMGF=1                        // to set modem in sms mode
Reply   <- OK                                             // modem send ok
Command -> AT+CMGS=”mobile number” // enter mobile  number
Reply   <- '>'                                               // > promt will come
Now type your message and press Ctrl+z. If everything will be fine then message will go successfully.