Serial and interrupt

[Archangel]

Thanks for the tip, but I have already bought the other one - as I said to late to change my mind. Anyway i've been doing some diggin and I'm going forward with the ASM serial routine part. There's only one little problem - the code I'm using gives me a "Symbol previously not defined" error. How do I setup variables so I can write to them inside the asm code and reuse them in picbasic?

I can answer that, I think. The name of your variable used in the asm routine needs to have an underscore preceding it in pbp, example:
_MyVar var byte