HDMI and Dreamcast

Discuss modifications you have done or plan to do to your Dreamcast or any other hardware, or discuss devices you want to build. If your console does not work or is acting up, ask about fixing it in here.
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Quzar
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Post by Quzar » Tue Jan 03, 2006 2:01 pm

yes, because tehre are two types of dvi, the ones that can do that, and the ones that can't. in this case you can't really convert from the analog vga to the digital hdmi without problems (which i didn't know).
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Post by Thomas » Tue Jan 03, 2006 2:06 pm

Prophet][ wrote:
Thomas wrote:I remember seeing some vga to component cables awhile back. They were around $120 though.
you sure that wasn't vga to composite. vga is pretty much component with extra signals for syncs and the like.
It was, my mis-type.
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Post by Lyris » Wed Mar 22, 2006 10:25 am

Actually the Xbox 360 doesn't have digital output. It's Analog only over Component.

A $10 VGA to Component cable won't work unless your TV specifically accepts RGBHV signals over the Component jacks (highly unlikely).

A Key Digital KD-VTCA3 transcoder ($200 or so) is the best option to convert the VGA 640x480 Dreamcast output into 480p to be input over the Component jacks.
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Post by fatheadpi » Wed Mar 22, 2006 3:01 pm

Hey Lyris, I've been looking for a converter like that for a while as my TV accepts up to component video. What would the quality gain be on a 42 inch TV using VGA to composite versus using straight S-Video?
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Post by Lyris » Wed Mar 22, 2006 5:05 pm

You mean converting a VGA signal to Composite? It would look worse than S-Video. In fact, the native Composite output of the DC would probably look the same or better.
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Post by fatheadpi » Wed Mar 22, 2006 9:16 pm

Der, stupid close-sounding video terms. I meant component, not composite. So yeah, between VGA - COMPONENT video vs straight shot s-video which would look better, and what would be the quality difference?
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Post by Prophet][ » Wed Mar 22, 2006 9:26 pm

VGA --> component, would have pretty much no loss as most of it is straight through.

Image

VGA --> composite, would have severe quality loss and is not worht it unless you really need to.

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Post by fatheadpi » Wed Mar 22, 2006 10:36 pm

So the difference of using s-video vs using VGA - component would be about the same difference (quality wise) as s-video and VGA , correct? Would this be as noticeable on a 42 inch projection TV where my input options are s-video and component video? Also, would this setup be fine for feeding my PC into my television?

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Post by Prophet][ » Thu Mar 23, 2006 2:25 am

fatheadpi wrote:So the difference of using s-video vs using VGA - component would be about the same difference (quality wise) as s-video and VGA , correct?
Indeed.
Would this be as noticeable on a 42 inch projection TV where my input options are s-video and component video?
I wouldn't think you would notice any difference between component and vga. So I would rather turn a vga plug into a compont then use s-video
Also, would this setup be fine for feeding my PC into my television?
My mate does this on his 106cm plasma and it looks aswome. (as long as your TV can take the resolution)
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Post by Lyris » Thu Mar 23, 2006 6:29 am

So the difference of using s-video vs using VGA - component would be about the same difference (quality wise) as s-video and VGA , correct?
Component done properly would give you 480p which is a huge leap over S-Video (which in America has 480i maximum). There's better colour resolution as well.

As Prophet said, between Component and VGA there's hardly any difference (unless your TV is very lousy at handling Component, but that's very unlikely).
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Post by fatheadpi » Thu Mar 23, 2006 9:55 pm

Killer, hink I found my next upgrade for the compy and the DC. Saw one or two full on converters on the web for around 120, gotta pick one out. Too bad the all-in-wonders don't have a VGA input or I could just put that cash towards a new GFX card.
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Post by Prophet][ » Thu Mar 23, 2006 10:09 pm

you mean $120 for a VGA to component? thats a rip. You could make one for $10 using that circuit diagram I posted above.
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Post by fatheadpi » Thu Mar 23, 2006 10:20 pm

Know any place I could buy a prebuilt board? Between my job and OC'ing some DC's I've lost ALL interest in building circuits for a while.
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Post by Prophet][ » Fri Mar 24, 2006 12:44 am

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Post by fatheadpi » Fri Mar 24, 2006 1:02 am

Yeah, tried that. The only units I see tha are actual boxes to do what I need start at $140. I'm pretty sure you can't just use the VGA- component cables as I don't think they have the IC in them.
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Post by Lyris » Fri Mar 24, 2006 8:54 am

Prophet, that diagram you posted - how would I go about using that to make a VGA to Component box? Wouldn't I need a chip to do the RGB to YPbPr conversion and also combine the Composite Sync and Y outputs?
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Post by Lyris » Fri Mar 24, 2006 4:01 pm

BTW Prophet, just had a better look. That diagram you posted wouldn't work. It just converts RGB to RGBHV. Component needs RGB converted to Colour Difference Video (YPbPr).
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Post by Prophet][ » Fri Mar 24, 2006 9:53 pm

Lyris wrote:BTW Prophet, just had a better look. That diagram you posted wouldn't work. It just converts RGB to RGBHV. Component needs RGB converted to Colour Difference Video (YPbPr).
That is different type of component. Their is more than one type, about 6 that I know of. So yea, it does depend on what your TV takes and even where you live. But traditional component is just RGB, and I *think* most newer TVs can tell the difference between them and automaticly ajust to which your using.

Also, the sync is not needed on TV's like it is on mointers. I don't know about overseas but the TV's I've seen don't have a snyc on them (with component that is, obviously SCART can have this). The circuit for combining the snyc is very simple, you just need a couple of resisters, and XOR IC and a transistor.
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Post by Lyris » Sat Mar 25, 2006 7:34 am

Most consumer TVs will only take Y/Pb/Pr - RGB over Component is definitely not the norm. What are the other types?

Occasionally you'll find some TVs that let you choose: some Sharp LCD TVs let you choose between RGB and Y/Pb/Pr.
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Post by fatheadpi » Sat Mar 25, 2006 6:34 pm

If enough people are interested in getting this setup, I can try and find us a converter and scam for a wholesale deal. Still won't be cheap, but I can probably save us a few bucks.
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