C=128 80Col NTSC Color.
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From: Rick Balkins on 21 Mar 2007 23:25 C=VGA was to be able to hook up both the VIC-II video (NTSC or PAL) and the VDC video to the SVGA monitor in the same unit. "Brian Ketterling" <tweel6510(a)no-potted-meat-products-peoplepc.com> wrote in message news:1f4Mh.129690$_73.90907(a)newsread2.news.pas.earthlink.net... > "Joseph Fenn" <jfenn(a)lava.net> wrote in message > news:Pine.BSI.4.64.0703200844590.9569(a)malasada.lava.net >> On Tue, 20 Mar 2007, Brian Ketterling wrote: >> >>> Joe's Great White Whale was supposed to accept both >>> 40 column (NTSC or PAL) and 80 column Commodore video and convert either >>> to VGA. I think they also wanted to accomodate the video of other >>> "classic" computers. >> >> Yep your Exactly right Brian! Except you forgot about the part >> about "they suceeded in makeing the device for PAL useage, but never >> could conquer the problem with NTSC displays (for the C128 mode) >> that is. > > Well, I didn't forget the NTSC problem, but I was referring to their > intent. > I guess you could substitute "intended" for "supposed" in my sentence > above. > > I wasn't following Commodore news for a while, and I guess I missed the > point when the C=VGA project spun to a stop. Are you saying that 40 > column > NTSC worked when it was coming from 64's and 128's in 64 mode, but not > when > it was coming from 128's in 128 mode? That seems implausible (I hope > VIC-II-generated video doesn't have a secret embedded signal to tell the > monitor what mode the computer is in ;-)! ). > > Brian > -- > >
From: Mangelore on 22 Mar 2007 02:47 Brian Ketterling wrote: > "Rick Balkins" <nospam.rickbalkins(a)nospam.wavestarinteractive.com> wrote in > message news:B84Mh.370$vV3.154(a)newsfe02.lga >> ...I am addressing Mangelore's part and appeared to >> have provided an interesting input that seems to actually help. That is >> suprising in itself. > > Buck up, Rick -- your technical inputs are sure to find their mark now and > then :) . > > Personally, though, I wouldn't mind a "for-dummies" synopsis of Mangelore's > project. > > Brian Hi Brain, It's just a device that allows you to connect either the C128 RGBI 80 column video port, or an Amiga 500/600/1200 video port, to a VGA monitor. Cheers Fotios
From: Anssi Saari on 22 Mar 2007 14:13 Mangelore <fotios(a)commodore128.org> writes: > It's just a device that allows you to connect either the C128 RGBI 80 > column video port, or an Amiga 500/600/1200 video port, to a VGA > monitor. It's an interesting device though. Right now I for one have nothing to connect the RGBI from my 128 to and I don't really want to get an old CRT just for that. As rumor has it, you can use current Dell displays like the 2407WFP to connect an Amiga, since they accept the low sync rates via VGA. The monitor has composite, S-Video and component inputs too, so it makes sense. Haven't tried it yet though.
From: The Questarian on 25 Mar 2007 13:52 Rick Balkins wrote: > You're right Brian. > > However this thread began to evolve to a wider topic of converters suited > for C128 80 col. video. I am addressing Mangelore's part and appeared to > have provided an interesting input that seems to actually help. That is > suprising in itself. > Out or curiosity, I've run into a site that has a variety of video output format converts (cga,ega,vga,ntsc,pal, etc) at http://www.converters.tv/ and there are CGA to VGA, CGA to NTSC, and NTSC/PAL to VGA converters... some of them seem a bit pricey... has anyone had any experience with these boards and that vendor?
From: a7yvm109gf5d1 on 26 Mar 2007 00:39
On Mar 25, 12:52 pm, The Questarian <J.bie...(a)REMOVEMETOSEND.Questarian.com> wrote: > Rick Balkins wrote: > > You're right Brian. > > > However this thread began to evolve to a wider topic of converters suited > > for C128 80 col. video. I am addressing Mangelore's part and appeared to > > have provided an interesting input that seems to actually help. That is > > suprising in itself. > > Out or curiosity, I've run into a site that has a variety of video > output format converts (cga,ega,vga,ntsc,pal, etc) athttp://www.converters.tv/ and there are CGA to VGA, CGA to NTSC, and > NTSC/PAL to VGA converters... some of them seem a bit pricey... has > anyone had any experience with these boards and that vendor? It'll probably look like this, at best: http://upload.wikimedia.org/wikipedia/en/5/59/CGA_CompVsRGB_Text.png If your definition of "work" is whatever is barely legible in a fuzzy rainbow of shifting colors, more power to you, I guess. I point out that this picture on Wikipedia looks too good to be true, I don't know how they took it. As you can see, white text turns into a multi-color brew. I'd have expected worse. I also expect it to be shimmering constantly on a live screen. No way that's staying constant. The only way to get CGA properly encoded into an NTSC signal is with some sophisticated signal processing. That's why you have to pay for it, there's no demand for it. VGA to NTSC and NTSC to VGA is just as hard, but almost everyone has a use for that so it's mass produced, thus cheap. You have to read in a line with 16MHz pixel rate, then apply various algorithms to limit the bandwidth and encode the colors in ways that are compatible with the NTSC dot clock, and the limited bandwidth of the I and Q sub-carriers. Oh not easy at all. CGA to VGA is easier because you don't have to care about a tight relationship between clock frequencies because the colors are not encoded, they're just voltages on three wires as opposed to phasors buried in one wire. You just clock in the data at one speed, and toss it out at twice the speed. Assuming you can get a clean clock signal. Now if only someone could tell me why I can't get the LUT to work on my project... My VGA output is purple, but it's sharp! (More or less!) http://dfpresource.org/VGA_noLUT.jpg The blurriness here are JPG compression artifacts. Anyways, I hope people read that Wiki page, although it's vague on a few things it should clear things up. |