i set up the transmitters and one receiver and tested them using a wire form the rx porta,7 to the tx porta,6 one the other unit. All worked fine.
I then put the transmitters and recievers into the circuits and tested each transmitter. all worked fine.
i then put a transitor on porta,4 to switch the transmitter on only when data was to tranmitted.and a led to show when a signal was being sent. the transmitter sends the receiver gives an output to the receiver. but no data is received.
after a couple of hours of cursing i moved the le and transitor to portb and all worked fine. can anyone tell me why this could have happened. to check what had happened i put everything back on port a and nothing worked. so i will have to use portb for all my inputs and outputs.
if i simulate it in mplab it shows it works on porta.