#A1200 U.K. Stocks
Take a look at a zorro-ii video board, I think the picasso will run in an
a2000. This is better than aga and is only 16 bit.
AGA has many limitations, resolution and colour depth. These could be added to
an add on card, this would be good in itself.
AGA also has alot of speed problems due to design constraints.
Firstly when you are running in the highest resolution in 256 colour or HAM-8
then the processor has hardly any time which it can access video memory. When
the dma bandwidth is saturated the processor and blitter can only access chip
memory during the border areas being displayed. A pcmcia card could be designed
that didn't have this limitation.
Secondly AGA uses planar video, chunky video is much faster. If you want to
plot 1 pixel on a 256 colour screen it would take 8 reads, 8 modifies and 8
writes. On a chunky screen it would be 1 read, 1 modify and 1 write. The reason
that doom clones have been thin on the ground on the amiga ( and they still
aren't as good as the pc ) is because the amiga doesn't have chunky video
modes. These could be implemented on a pcmcia card.
Thirdly if you want to display 24bit pictures then you have to convert to 256
colours or HAM8, both of these take quite a long time to do. If you could
display 16 or 24bit pictures then there would be another speed advantage.
Just because AGA is 32bit does mean that it is better than OCS/ECS which were
16bit, it doesn't mean that it is better than any 16bit video subsystem.
Quite a few people are buying tower cases for the amiga1200 that gives you
zorro-ii slots so that they can run picasso boards etc. they wouldn't bother if
it was slower than AGA, would they?
I must admit that putting a video board in the pcmcia slot does sound a bit
strange, but it would be an improvement.
I just wish that someone would be willing to put research into this. It might
be possible to get a zorro-ii board to work by attaching it to the pcmcia port.
It of course wouldn't be able to do dma and other things that are supported by
zorro-ii, but to support one specific board it could work.
Phill