Date   : Mon, 25 Aug 1997 19:12:24 +0200
From   : "Mark Usher" <marku@...>
Subject: Re: Tube Documentation

Mark

> BPC is alive and kicking 
Where ? :-)

> enough that I'm after some documentation about
> the Tube (6502) hardware. Principally, the I/O and memory arena, but if
> anyone has a circuit diagram of the tube they can send me I'd be most
> grateful.
>
> The AUG states that all 64K is RAM in the tube - but there must also be
> some I/O somewhere in there ;-)
OK, I have one "lying" here in front of me. Looking at the board, I can
support that the 64K RAM is onboard - there are 8 x 8 mem chips with the
following ID
HM4864P-2, and although I don't have an RS catalogue lying around I'd bet
they're 8K chips - although I'm not too sure about the 2nanoseconds. The
Beeb even with a co-pro was never *that* fast :-)

Hmm, I/O, well they're definately is some other stuff on here. Apart from
the 74 logic gates etc etc, there are 3 other chips,  one is a 24pin Acorn
custom chip in a socket, (want an image ?), the other is a 65C02P3, hmm,
wonder what that is, I'll have to look it up... :-)  By the way, what is
the difference between 65C02P2/P3/P4 and 65SC02P2 ?
Clock speed ?

.....and finally, here it is, a Ferrari, whoops Ferranti ULA9C018E-7 8420.
I
think that's what you're after Mark.

As for a circuit diagram, well I must admit that is one of the things I
don't have...
I'll give someone a ring later though who I suspect might have one :-)

Mark Usher
marku@...
Programmer / Insoft GesmbH / Austria