Date   : Fri, 05 Jan 2001 20:55:56 +0000
From   : jgh@... (Jonathan Graham Harston)
Subject: Undoumented 6502 opcodes : BBC vs. Electron

Thomas Harte <t.harte@...> wrote:
> I'm fairly sure on here a while ago someone stated that the 6502 in an
> Electron reacts differently to at least some undefined opcodes when
> compared to the 6502 in a BBC Micro (specifically with reference to
> Zalaga I think). Is that correct, or did I misunderstand? If so, is that
 
Zalaga (or "Zalagan" as some people ;) knew it as) doesn't work on
non-BBCs as it uses a screen lookup table with OS 1.20.  You can get it to
work on that Masters as there is ram there (Hazel) and a small bit of code
can be used to create the table before running Zalagan.  I've been looking
for the relavant bit of code myself - it was published in either Acorn
User or Micro User some time ago.
 
-- 
J.G.Harston (JGH BBC PD Library) 70 Camm Street, Walkley, SHEFFIELD S6 3TR
jgh@...                - Running on BBCs & Masters with SJ MDFS FileServer
Z80+6502/CoPro+Tubes/Econet+SJ - - - - - - - http://www.mdfs.net/User/JGH/
                             Et In Arcadia Ego