Date   : Thu, 04 Jan 1996 10:36:21 GMT
From   : David Alan Gilbert <gilbertd@...>
Subject: Re:  Beeb emulator snapshot format

An idea and a question:  You don't have anywhere for the sound chip information.
Why not create a tagged file format which contains a number of sections
each starting with a keyword.  Emulators would only store information
for devices
they know about, and similarly emulators could ignore sections for hardware
they haven't got while its loading state in.

What is the 'number of outstanding IRQs' field for - I don't keep a count,
I keep a bit field of who is generating IRQs/NMIs.

I think there are also issues about exactly when the snapshot is taken - for
example my code is basically:

while 1
  execute intruction
  Check for interrupts
  poll hardware
end

Where exactly is the state stored/loaded - the different places it could
go in that loop could produce subtly different results if you are very
unlucky.

Dave