Hello all,

I've built the Serial I/O expander that is detailed here. The only difference in my circuit is that I'm using a Pic16f818 (what I had laying around) and am driving simple LEDs instead of relays. My problem is that I can't seem to talk to the pic via Hyperterminal or other PC serial terminal programs (for example the Serial Communicator within MCS). I have COM port pin 3 hooked up to RA4 via a 22k resistor and COM port pin5 hooked to ground. I'm setting up the terminal program as 8bit word, 2400baud, non-parity, 1 stop bit. I open up hyper terminal and type in 254,1,1 and get nothing. Not sure if it's an issue with syntax. I've tried the following...

254,1,1
254 1 1 1
254:1:1
25411

I've added a few LED flashes before the loop in the program to ensure that the pic is alive and it is. I also added a quick flash at the end of Loop: so that I can see when/if the pic actually goes through this subroutine. From what I can see, it never does. It looks like it is just hanging on the Serin command.

What am I missing. Really hoping this is something silly.

best,
Brad