Date   : Thu, 05 Oct 2000 21:38:56 +0000
From   : Michael Foot <mikef@...>
Subject: 6522 VIA

OK, for starters I've put together a 'C' code style notation of how I think 
the 6522 VIA is emulated in code. It's not 100% correct by any means and 
it's also missing bits of the timing like clock stretching when the VIA is
accessed. It will work with the majority of bbc software out there but there
are still some games (like Rig Attack) where it won't.

Anyway, I'd appreciate it if all you emulator writers out there could take
a look at it and see if you can fill in the gaps. Here's hoping to get it
pretty accurate ibn the near future.

The URL is:
http://www.voyager.co.nz/~mikef/bbc/r6522.txt

Thanks,

Mike.

In message <NABBKDNBEOKOCFKNJILIOENIFGAA.mu.list@...> you wrote:

> > Related to this question is an idea I've been thinking about for
> > some time. I would really like to see a central repository of
> > information and data that would help writers of BBC emulators to
> > write them properly.
> 
> > What does everyone else think?
> Sounds good to me. It could be created as an extension to the documentation
> project.
> 
> This also relates back to what Dave Gilbert was saying, and which I agree
> with. It would be far better to take some of the open source emualtors like
> BeebEm and improve on them rather that continually re-invent the wheel
> writing new emualtors. Mind you, I suppose an emualtor is also re-inventing
> the wheel in its own way, not quite, but almost.

-- 
Michael Foot <mikef@...          >
http://www.voyager.co.nz/~mikef