GSM interfacing with microcontroller

When checking, debugging, etc, have you done to find out why it is not working?

When checking, debugging, etc, have you done to find out why it is not working?

In my code i am getting the gsm data through UART1 interrupt, i am connecting GSM modem to the UART1 port.
the modem is working properly with hyperterminal, but not with microcontroller.

Sorry - I meant, What checking, testing, debugging, etc, have you done to find out why it is not working?

ie,

Have you checked your connections between the microcontroller & GSM module?

What testing have you done to ensure that your microcontroller is sending & receiving characters correctly?

What debugging have you done to see that your code is correctly handling the sent & received characters, interrupts, etc?

Does the GSM module use compatible voltage levels as the microcontroller?

Have you checked if you need to handle any handshake signals?

I HAVE CHECKED THE CONNECTION BETWEEN BOTH microcontroller & GSM module.
the modem is working properly with the hyper terminal.
In my code i get the input from GSM modem via UART1 interrupt.
I tested the code by sending & receiving messages in both direction(two & fro) hyper terminal/Hercules to the microcontroller
i am able to send messages from micro controller to mobile via GSM modem.

i am using SIMCOM_SIM300 gsm module where i have shorted 7 and 8 pin ie RTS and CTS.The other RS232 pins tx-rx and rx-tx and GND are connected accordignly.
THE MODEM IS SUPPLIED WITH A 9-12V DC SUPPLY.

the GSM module dosn't have compatible voltage levels as the microcontroller

So it's working now?

Well done!

No,
there is no communication taking place from gsm modem to microcontroller via TX(modem)to RX(microcontroller)through UART1 interrupt

So why did you say that you are able to send messages?!

"TX (modem)to RX (microcontroller)"

Read the modem datasheet again very carefully - pay particular attention to the directions of all signals.

Assume nothing - read carefully.

Also try searching this forum for "DTE" and "DCE"...

Can you please explain how to send message to a mobile phone by interfacing a gsm to a micro controller and programming the micro controller.

This is a very, very, very common task - so there is really no point in repeating the explanation yet again.

So-called "Search Engines" are very powerful tools for finding stuff on the Internet; eg,

www.lmgtfy.com

And here are some general tips on interfacing: www.8052.com/.../160143

interfacing is done through UART controller by setting its baudrate to the GSM baud rate. and give the corresponding GSM send command from the micro controller + the number and message as we do in PC .