Re: Apple ][ to VGA monitor adapter board - looking for best color decoding method

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

ferd...@gmx.de wrote:

> 1. Latch the video signal 4 times at different phases to  COLOR
> REFERENCE. (7M rising, 14M falling with 7M high, 7M falling, 14M
> falling with 7M low - note that COLOR REFERENCE becomes 7MHz after the
> conversion). These 4 signal are mixed to form the 3 colors. This
> method gives exact reproduction of the 15 LORES colors (I designed it
> to do so) but blurs the picture in HIRES.

This approach provides essentially a 'scan-doubled' equivalent of what
Apple II RGB cards produced.

Personally, this is my preferred approach, and would happily pay a
reasonable sum for such a board. The harder part will be the DHR
modes, which can be encoded as either colour or monochrome, or both.
Mimicking the technique used by the RGB cards seems the best approach.

Matt