25 Jan
2010
25 Jan
'10
4:25 a.m.
On Sun, 24 Jan 2010, Cameron Kaiser wrote:
Yes, that's the one. I run into the RGB input. I actually think that it
can handle NTSC composite input as well, but have never tried it.
How do you have it connected to the IIgs? What pins do you have where?
Thusly:
http://vintageware.orconhosting.net.nz/apple2/scart.html
You may need to expirement a bit with the sync. I got my best results
using the pinouts at the above web page (IIgs composite sync output).
Others have reported that using the IIgs composite _video_ output produced
a clearly display. So, best to assemble things at the computer end to
permit this to be switched.
The function-select and RGB control voltages are derived by using series
resistors from the IIgs +12V out. That's probably fine for
function-select, since it wants 9-12v for "AV" mode, but for RGB control
it relies on the internal impedence to provide the bottom leg of a voltage
divider. It works (shrug), but isn't a terribly elegant approach.
The only visual artifacts in my case were some very fine vertical lines.
I don't find them very obtrusive, but YMMV. Folks on comp.sys.apple2 have
suggested that low-pass filters in the video signal lines might help.
Never tried it.
You can peruse many threads of discussion on the issue of IIgs video
conversion by using Google Groups to search the csa2 archives.
Steve
--
I've had
great results from the Highway 100 scan converter. It's a bit
pricey, but produces a rock-solid scan-doubled image from my Amiga 2000 in
interlaced 640x480 mode. It even supports the somewhat (well, very)
oddball color output from an Apple IIgs.
Steve, is this the one you're talking about?
http://www.converters.tv/products/pal_to_vga/100.html