I am interfacing gsm sim 900 with At89c52.I hav gone through all the AT commands.I have tried dem on Hyperterminal.I want to know how do we send a message from our mobile device to gsm modem and how to transmit it from modem to microcontroller.What commands to use!?? I have tried sending msg from pc to mobile..Pls help
Nothing specific to 8051.
This should be possible using entirely standard AT Commands - so not even specific to SIM900.
Nothing to do with Keil!
"I have gone through all the AT commands"
And what was your conclusion from that exercise?
"I have tried dem ["them"?] on Hyperterminal"
And what was the result?
"I want to know how do we send a message from our mobile device"
Read the documentation for your "mobile device" - whatever it is.
"to gsm modem"
Think about it: as far as sending SMS is concerned, the destination is just a phone number - isn't it?
"how to transmit it from modem to microcontroller"
I thought you said you'd studied all the AT commands? And tried them on hyperterminal?
"What commands to use!??"
See above!
"I have tried sending msg from pc to mobile."
And what was the result? What was your conclusion from that exercise?
"Pls help"
You're really not giving much to go on!
It's not like there aren't already plenty of examples on the interweb...
www.catb.org/.../smart-questions.html