Date   : Thu, 18 Aug 2011 11:55:29 +0100
From   : adsb@... (Andrew Benham)
Subject: Tube ROM

On 17/08/11 18:07, Rick Murray wrote:

> A question I have is if HiBASIC is present as a BBC Micro EPROM, but it 
> won't work unless it is copied onto the co-processor, why is it not part 
> of the co-processor firmware, and just copied into RAM at startup? It's 
> a bit dumb for the co-pro user guide to suggest it is "best" to start 
> with both BASIC and HiBASIC installed, as well as the Beeb MOS, plus a 
> DNFS for the Tube interface code. That only leaves one ROM slot on a 
> standard Beeb...

My recollection, which may be wrong, was that HiBASIC wasn't supplied on
a ROM but just as a image on disk.

Acorn's Alternative MOS ROM for the Master includes ROM relocation code,
and the version of BASIC in that MOS ROM automagically relocates itself
on a 6502 second processor upon a reset if BASIC is the configured
language.  The ROM responds to both *BASIC and *HIBASIC - the two
commands giving two different load addresses.
The version of EDIT also relocates itself higher in a 6502 second
processor.

-- 
Andrew Benham     Southgate, London N14, United Kingdom

The gates in my computer are AND OR and NOT, not "Bill"