Some advice. Always use a hardware UART when you can.

I do bullet proof comms using an asm routine and a harware UART. However, if I had a small program and I didn't want to write an assembly interrupt service routine then I would simple poll the interrupt bit. This bit will set whenever a character has come in. It will clear when you remove the character.

So what chip are you using? Does it have a UART? Can you use it?

Hope this helps,

Joe.