Date   : Tue, 01 Aug 2006 13:20:52 +0100
From   : jgh@... (Jonathan Graham Harston)
Subject: Re: Advanced BASIC and copros

Steve Fewell <kranser@...> wrote:
> The patched ROM makes use of a new OSWORD call (&B2)
 
The patched ROM? I though Advanced BASIC used the original, ie
*unpatched* BASIC, and modifed the code in RAM on the language
side of the Tube.
 
> My question is, what happens when the new OSWORD call
> is made from the patched ROM (which does happen)? Will
> the original ROM be loaded accross the Tube and
> overwrite the new patched ROM?
 
>From the ROM (ie, the I/O processor) or from the Language? In
either case, the I/O processor will call the ROM's service entry
and the ROM's service handling code will deal with the OSBYTE.
Whether that OSBYTE is a call to copy something across the Tube
will determine whether anything is copied across the Tube or not.
 
All service routines are executed in the I/O processor; a service
routine is not a language, it's a service routine.
 
-- 
J.G.Harston - jgh@...                - mdfs.net/User/JGH
There are three food groups: brown, green and ice cream.