angstrom serial port bug

hi all,

i tried to read write the on board serial port of beagle board from ansgstrom linux. i tried this using python and C and have done this before in desktop.
but even thought the port is initialized with the settings i done i cant read the data from the serial port. i dont know whats happening with write cause there are no error outputs when i run the binary or python script. some times it just works for a while and the same occurs again. is this because angstrom uses the on board port to display console. pls tell me how to get through this.

Use “cat” to data exchange at both sides of the connection, then use your own program