UART assembly routine

[ChristofferB]

Aand now we're done. Got it working at last! It was the clock, it must've run off of noise all this time. Putting in a 9MHz can oscillator and removing the xtal capacitors and now it just runs. Here's proof and a portrait.

This fault obviously accounts for most of the larger issues I've had with this the last year, maybe actually measuring frequencies with a scope instead of just going 'yep, there's a signal' is a wise idea..

Thanks for all the assistance!