I’m trying to communicate to a telit gsm module over COM3 on my FEZ Mini. COM1 is used for Debugging, COM2 for talking to a GPS module (works fine). I had to install a level shifter that the communication with the Telit module works (3,3 <–> 2,8 V). When I’m talking over a TTL to USB Module to the Telit Module everything works fine. Now I just soldered the module to my COM3 but the Communication doesn’t work. I’m always getting back what I sent out.
I’m using this test code:
byte shdn = System.Text.UTF8Encoding.UTF8.GetBytes(“AT#SHDN\n\r”);
gsmPort.Write(shdn, 0, shdn.Length);
byte gsmbuf = new byte;
gsmPort.Read(gsmbuf, 0, 10);
Normally the Module would respond with “OK” but I’m getting back “AT#SHDN\n\r”
I checked for solder bridges, changed RX/TX but nothing.
I’m really confused right now, thx for your responses.