Hello all.

I am using PICBasic Pro to program two 16F877As that are cross linked via portb.4 and portb.3. On both MCUs i am using portb.4 as the TX pin and portb.3 as the RX pin. Using the serin2 and serout2 functions, i have been able to transmit data through a max232 converter to the PC with no problem whatsoever. I even have it working wirelessly through Linx Technologies' ES Series RF modules, which is what i want to be using when all is said and done.

However, going from PC to MCU is a different story. At first I tried that to see if the PIC could read information by waiting for the ascii string "start" and then lighting an LED. I sent the string through LabVIEW, and I know it works correctly because of a few tests i did. It only lights when I send about 20 "start"s over the TX line in rapid succession. I then configured another MCU to 'talk' to the previous one, hard wired as described in the first paragraph. Again, this works intermittently.

I find it strange that with no hardware changes the PIC can transmit data correctly to the PC, but the same data cannot be read by another microcontroller at the same baud rate and settings. My feeling is that the controllers are becomming out of sync, even though this is asynchronous serial communication. If anybody has any suggestions or comments or questions please let me know. Thanks in advance!

Cameron