Re: Apple IIc plus RGB video?

["mdj" <mdj.mdj@gmail.com>]

Jorge Chamorro Bieling wrote:
> mdj <mdj.mdj@gmail.com> wrote:
>
> > I don't think the connector provides everything one might want, either.
> > For instance, it'd be impossible to produce Double-Hires Mixed-Mode
> > from the provided signals,
>
> Why do you think so ?

It seems reasonable that such a device can actually generate every
video mode supported by the IIe RGB adapter, my doubts are around how
the device detects which of the 4 documented modes the machine wishes
to be in, given that it has no access to the address bus, and cannot
detect a state change on AN3

http://www.freepatentsonline.com/4631692.html

The above is VIDEO 7's patent on the IIe RGB adapter. As I understand
it, Apple AppleColour card was a product licensed from VIDEO 7. The
other RGB adapters, ie the ones supplied by Applied Engineering,
Checkmate Technology, etc adhere to the same rules as the VIDEO 7 gear,
although the 160x192 mode is not discussed in the Apple documentation,
only VIDEO 7's.

There is in fact, one other RGB mode available. If you're interested
there was an Apple Assembly Line article on it that's available on Bob
Sander-Cederlofs site.

I'd be interested to see the documentation for the IIc RGB adapters to
see if they indeed support these modes, and how it is that they achieve
it, as I've never seen one myself, and cannot tell from my knowledge of
IIe RGB adapters how a IIc device could behave the same way. If anyone
knows how this works, or can scan a copy of the documentation, I'd be
very keen to see it. Existing Apple II RGB technology vanished into
obscurity very quickly after the launch of the IIGS (which ignored the
modes that Apple had already sactioned)

Matt