Date   : Sat, 30 Dec 2000 04:21:30 +0000
From   : Ben Newsam <ben@...>
Subject: Re: BBCBasic Was: More T102 Stuff

In message <001223200001@...>, Jonathan Graham Harston
<jgh@...> writes
>philipp@... wrote:
>> you probably know, but BASIC 3 was only published on the US versions of
>> the BBC micro (i think) so looking for retro computers in America may be
>> your best bet
> 
>Yes, it defaulted to listing COLOR instead of COLOUR.

I never had BASIC 3, but I was supplied (by Acornsoft) with a special
chip that allowed the used of the OS intended for use on American
machines to be run on the British Beeb. It has one leg missing
(intentionally), and there is a connection between two of the other
pins. Having to maintain compatibility with that was a right royal pain.
Apart from the different screen resolution (and thus aspect ratio),
there were five fewer lines in MODE 7.

The "official" way I was told to detect the US MOS was that on a British
Beeb, INKEY(-256) would return -1, whereas in the US it would not.
Unfortunately, I took them at their word, and wrote some software
accordingly. Then along came the Master, which returns 253 for the same
call, so all my "IF INKEY(-256)=-1" lines were no longer valid in this
country. Hmmf.

Does anyone know how INKEY with such negative values actually works?
-- 
Ben