Re: Apple II VGA Video Generator Card Project

[bieling@terra.es]

aiiadict@gmail.com ha escrito:

> I added a link to your site on mine
> (http://rich12345.tripod.com)

Thanks, now I'm a "hardware hacker" .. :-)

> If you design the card using programmable
> logic, extra (non compatible) video modes
> could be added at any time.
>
> perhaps put a mechanical switch on the
> card that connects the PROGRAM pins
> of the logic device to the address/data
> bus.  Re-Program the device (new program
> loaded off disk), flip the switch (no slot addresses
> taken by the card any longer), and you've
> got new logic on your card..

That's a good idea, only that it may be another whole project in
itself, it may mean much more development time and effort.
Don't you prefer to have this asap ?
Of course programmable logic is "the way to go".
So we better start learning some hdl...
The address scanner and the pixel generator can be made programable via
software up to a certain point, more or less like the 6545 in the videx
is: Bytes per scan line, lines per frame, graphics buffer start
address, etc. As long as the resulting frequencies fall within the
monitor specs and the memory map permits, all will be ok.