Date   : Mon, 07 Sep 2009 16:00:48 +0100
From   : robert@... (Rob)
Subject: Acorn World '09: Final Layout & Wiring Plan

On 07/09/2009, Phil Blundell <philb@...> wrote:
> FWIW, if you have at least one free sideways slot then it's fairly
> straightforward to fit 32K of SRAM (and probably feasible, though
> somewhat more fiddly, to fit 64K).  Of course, if you have enough
> machines already then it might not be worth the hassle.

Yups; my 'original' Bs already have that done, for socket E, via cut
tracks and links on the underside of the motherboard.  If I need to do
it to another one, I'll just solder to the legs of the chip!  (62256s
were somewhat more expensive, back when I did the first ones, and so I
treated them more gently!)

>> Oh ... and why would a Model B give me an inverted, black-on-white
>> screen??
> I think that's the symptom of having S26 set wrong for the type of
> VIDPROC that's fitted.  Try moving it to the other position and see if
> the situation improves.

Ah, ok, thanks!  I'll try that!  Messes up the composite video output
to the point where you can barely see a picture..  Was only when I
plugged it into a cub did I find out it was inverted..

Rob