Date   : Sun, 30 Oct 2005 20:51:22 -0000
From   : "David Hunt" <dm.hunt@...>
Subject: Re: BBC using 3.5 high density format

> -----Original Message-----
> From: Majordomo List Manager [mailto:majordomo@...] On Behalf Of
> Greg Cook
> Sent: 30 October 2005 20:32
> To: bbc-micro@...
> Subject: RE: [BBC-Micro] Re: BBC using 3.5 high density format
> 
> On Sun, 30 Oct 2005 10:17:41 -0000, Mark Usher <mu.list@...> wrote:
> 
> > Could not the timing scenarios be tested by using an emulator, adding
> > in
> > support for a 1772 and adjusting the timings for testing accordingly?
> 
> And how would you assure yourself that the 1772 emulation was accurate?
> :-)  The VIAs took years to perfect, and Kevin Edwards' protection
> schemes were available as a benchmark.
> 
> Greg

I was wondering why the 1772 was being chosen, it is a very hard part to
source, only 2nd computer scrap dealers have them. 

e.g. <http://www.best-electronics-ca.com/custom-i.htm> at $18 each.

I remember looking at an alternative to the Intel 8271 - the Intel 8272.

That was about 20 years ago, I had the datasheet - reading it was as far as
that went.

It has a number of successors that are still compatible e.g. 82078. This
part also has a 16 byte FIFO, might help with the page boundary problem? 

Just a thought...

Dave ;)