I am using hypertrm for communicate with gsm modem,my problem is i am not using "local echo",but characters are displayed on hypertrm when i used key board storks,and it was not shows the responses from the modem, please tell me what is the problem?
It wasn't a comment to your comment, but a comment to the OP :)
Anyway, if the terminal program can't receive any characters, then the normal route to check is: - is there a MAX232 or similar level converter between the microcontroller and the RS232 serial port. - are all wires connected correctly, so rx/tx hasn't been switched, or the receiver and transmitter halves of the level converter switched. - let the microcontroller send out data, and verify that it sends anything. - verify that the bit lengths of the data sent by the microcontroller has the correct baudrate. - verify that this data reaches the PC (and with the correct signal levels) - verify that the PC terminal program has the correct communication settings (including turning off any hardware handshake, unless the port is expected to use hw handshake)
yes thanks i got the problem ,its nothing but wired problem