Date   : Thu, 19 Apr 2001 14:20:01 +0100 (BST)
From   : jim <jim@...>
Subject: Re: Inter Word?

On Wed, 18 Apr 2001, Adrian Vico wrote:

> I noticed this ROM labeled (inter WORD)on my BBC B, and was just
> wondering what it was. 

It's a word processor, and rather a good one. As close as the Beeb ever
got to wysiwyg.

Incidentally, the interWORD ROM itself is quite interesting. Notice that
it's taller than a normal ROM and has some extra electronics between the
chip itself and the mounting. It's actually a 32K ROM which uses some
clever widgetry to make it appear to the Beeb as a 16K one. The high
address line of the ROM is latched by the little chip underneath, and
toggled by accessing special memory locations near the start of sideways
ROM space. There is indirection code duplicated in each 16K bank for
calling between them, which also checks that the sideways ROM IDs are the
same for each bank (so you can't pirate it by burning it to 2 16K ROMs or
sideways RAM, not hard to get round though, not that I'd know >8-) ).

jim
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