Date   : Tue, 29 Nov 2005 13:11:20 +0000
From   : jgh@... (Jonathan Graham Harston)
Subject: Re: Memory

"Scot Jones" <scot@...> wrote:
> I've a BBC-B with the standard 32k of memory.
> Is it possible to add memory to the machine?
> If so what would I need to do it (i.e. type of hardware etc)
 
Shadow RAM, which puts the screen in seperate memory to the
program, resulting in HIMEM at &8000 in all screen modes. Not a
self-build job. The best system is the Aries B32, followed by the
Aries B20. There is also the Watford Shadow RAM which is OK, but
I would recommend the Aries board in preference.
 
Sideways RAM, which gives you memory at &8000-&BFFF that you can
load sideways ROM images into, or store certain data in. Easy
self-build job. A 32K SRAM IC plugged into a sideways ROM socket
and a flying lead to IC77 pin 8 (I think) to collect the WR signal.
 
Search the archives for detailed construction info.
 
You can also use sideways ROM/RAM boards, such as the 12-ROM or
13-ROM boards from various manufacturers. These give you a full
complement of 16 sideways ROM sockets, and most also have one or
two banks of sideways RAM.
 
-- 
J.G.Harston - jgh@...                - mdfs.net/User/JGH
Jet Set Willy Resources - http://mdfs.net/Software/JSW