Re: Compact Flash card project for Apple II / IIGS

[mjmahon@aol.com (Michael J. Mahon)]

TheByteBooster wrote:

>"Tim Haynes" <timhaynes@no.spam.please.alumni.uwaterloo.ca> wrote in message
>news:<ci7e0s$299$1@rumours.uwaterloo.ca>...
>> "Bill Garber" <willy46pa@comcast.net> wrote in message
>> roGdnXJhMab5v9rcRVn-jA@comcast.com">news:roGdnXJhMab5v9rcRVn-jA@comcast.com...
>> >
>>  ...
>> >
>> > I think what people want mostly is a card to take the
>> > Apple II modes and display them on a VGA monitor. Yes,
>> > a full-featured VGA card would be nice, but what say we
>> > get a converter card just to display the Apple screens
>> > onto the VGA monitor for now. Add a connector so you
>> > can create a daughtercard later and install the VGA modes
>> > to it at a later time.  :o)
>> 
>> I agree.  I think most people would want a SecondSight kind of a card.
>> Except with DHR support and not being such a power hog.
>> 
>
>Well this is a completly different beast. Such a converter would have
>no "inteligence" and be rather "simple" to implement. Such a thing in
>fact would have not much in common what I think of a graphic card but
>rather be an interface/converter at best.

I agree.

But the conversion needs to be synchronous with the Apple II
video dot clock, and that's where virtually all of the "external"
converters fall down.

>Actually I think the SecondSight is all any Apple II users would
>need... Is it no longer manufactured ?!

You may be surprised to hear that the SecondSight card is
much like your own design in principle.  It "emulated" the
Apple display modes by using firmware on an onboard
processor to "snoop" video RAM and to control a VGA
video generator chip to produce an equivalent display.

Clearly, the "hard way" if the goal is to simply convert
Apple II video to VGA, but it also aspired to more advance
native modes (which were, of course, not exploited by any
significant amount of software).

-michael

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