specific call with SIM900 !!

[kkny]

hi everyone !!
i work on my project with SIM900 to give a specific call :
so i want to make a call, wait until i get a couple ring tones (or couple seconds) and then hang up the call (before the GSM receiver picks up the call)
the problem is that i don't know when the GSM receiver start ringing !!!
i used "ATX4" and i get no response from SIM900 when the GSM receiver start ringing !!
i used "ATS7" and it's not so accurate it depends on the GSM network !!

anyone who could help me please !!

 

[samuelr]

If I am not wrong, when a call comes in you should get an unsolicated message RING/r/n RING etc. Did you turn on the unsolicated message option?

 

[kkny]

Hi !!
yes i did and yes it works..thank you !!