Modem responds with junk value for AT Command using serial programming

Question

Background

I am trying to connect to a serial GSM - modem of Wavecom type.

I was able to communicate with the modem using the guide http://www.easysw.com/~mike/serial/serial.html

on my Ubuntu machine.

but when I tried to connect it through a device with serial port and running on Linux kernel Linux 2.6.14.7-tiny1-WR1.3al_small I get junk data returned. I have tried all of the baud values to connect to the modem. It connected on 115200 baud value when it was working, but the same value does not work from this Kernel. Its a ARM target machine. note : I cross compiled the code for ARM

Question

Do I need a driver for a modem to just be connected through a serial terminal Program ?

Answer 1

Please make sure that the RS232/TTL converter of your ARM board is working correctly. for example you can connect it to your Ubuntu machine at first and transmit something with a terminal program.

question : 1 ) Do i need a driver for Modem to just be connected through a Serial Terminal Program ?

No.You can connect to your GSM modem simply by having a serial port and a terminal program.