Date   : Tue, 26 Oct 2010 07:39:25 -0500
From   : jules.richardson99@... (Jules Richardson)
Subject: Reversing the Tube ULA (destructively)

Mark Haysman wrote:
> Have to agree that an "exact" clone would be preferable. I'm working with Ed 
> and Richard on his open source tube code to try and get it 100%, but there 
> seem to be odd quirks in there that would be a lot easier to solve if Ed 
> could have success with a proper RE of the original chip.

First I've heard of that.  I was trawling through ex-Acorn code and binaries 
last night which, aside from coughing up the delightful phrase "happy sperm 
tank", seemed to imply that there were a few glitches in the original ULA 
(generating spurious interrupts and whatnot) which the software then had to 
cope with - so quirks sounds about right.

(I probably have original Acorn source for TUBE access in ARX and Panos, by 
the way - let me know of you want me to go digging and see what I can find. 
Possibly some stuff on the beeb MOS side of things, too)

cheers

Jules