i am using proteus to simulate my project that has an avr microcontroller controlling relays ,the avr is interfaced or attached to the gsm modem sim900d , call on gsm modem from stored number would activate the relay for a short period of time..
now i am using the compim to attach the modem to the simulation
i can read sms , extract the number and message..
but the problem is whenever there is a call on the number the RI pin 9 of compim is set, and i also see blinking on RX pin ,but no message is displayed on the VTERM, instead the the RI line hangs up set only and no further response is available from the modem, i am using the development kit from simcom,
i would attach the proteus pics after recieving call theere is no ring and +clip on rx terminal and RI is all time red