Date   : Fri, 19 Oct 2007 17:49:59 +0100
From   : public@... (Daniel Beardsmore)
Subject: 12 kB Sideways RAM in a B+?

The manual confirms it -- the B+ has 12 kB Sideways RAM. It's not enough to
host a ROM image, being 4 kB short of one page, so why did Acorn only fit 12
kB instead of 16?

The B+ manual doesn't seem to cover it at all. I've never seen Sideways RAM
documented anywhere -- like an OS call to find out how many banks you have
of it, which they are, and how large each one is. Clearly you'd need
dedicated calls like this if you can't even rely on having a complete bank!

I don't know for example how Quest Paint recognises Sideways RAM when
looking for the extra 5 kB buffer it needs to back up the screen behind a
menu. Or how you detect Shadow RAM for that matter ...

Any clues?