Hi!
Usually, when I have this message is because the MCU hangs at some point. A possible problem is as Kef said, that stack is too small. Other can be invalid address writing.
Another problem related to the stack is that maybe you've got a variable (let's say a buffer 3 bytes long) and you're writing more than this lenght so the routine overwrite the return address on the stack.
I will try using breackpoints to determine where the error ocurrs
Regards!
PS: Please excuse my english.
Sebatian M. Irazabal
Rosario, Santa Fe Argentina