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

[sicklittlemonkey <Nick.Westgate@gmail.com>]

On Apr 9, 7:32 am, ferd...@gmx.de wrote:
> Hi all!
>
> With the understanding of the decoder circuit (I got the schematics
> from Marcus Heuser - thank you!)
> I was able to optimize color displays. The principle of the Shift
> register/latch circuit delivers a very poor picture if a different
> resistor network is connected to get RGB output. This was unusable, my
> method was far better. But, based on the resistor network  of the PAL
> color card, I was able to recalculate my values and got to this:http://img87.imageshack.us/my.php?image=comparisonau3.jpg
> The lower monitor is a 14'' NTSC device connected to the video out,
> the upper monitor is a 12'' IBM VGA connected to my card.
> I also tried some games:http://img301.imageshack.us/img301/1107/pacmanxj0.jpg(HIRES)http://img87.imageshack.us/img87/2020/airheart1vgand9.jpg(DHIRES)
> I'm just wondering how to continue. I might finish the PCB layout
> tomorrow, so I need to decide whether I make a prototype on my own -
> which is a lot of work (566 pads/204 vias) to be done or if I decide
> to let some guys make the PCB. But a 268mm x80mm is going to be
> expensive in prototype volumes (i.e. 1 or 2). It seems that PCBs are
> way cheaper in the US than in Europe...why? I might actually let them
> make in the US and ship them here.
>
> Ferdinand

I don't understand. The colours are fine, but the vertical striping is
completely alien to me. Does anyone else actually want it this way?

Using an Apple II+ with RGB as a kid, then a PAL Apple //e, then RGB
Apple IIGS, and finally NTSC //e's and NTSC and RGB //c's here in
Japan, I've never seen that kind of vertical striping.

Your "Method 1" images earlier looked better, though still not as good
as plain old GS mode emulation. Is it that hard to do? I'm asking as a
potential customer, of course. Not belittling your work. I want to
want this card! ;-)

Cheers,
Nick.