VGA to RGB

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bacteria
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VGA to RGB

Post by bacteria »

I have one of these screens:

Image

Clearly the PC-RGB is VGA for computer input; so will use H-Sync and V-Sync. Makes it fine for running off a PC or DreamCast I guess, but i'm after standard RGB we tap off regular consoles; so RGB plus C-Sync

Anyone know a cheap and easy way to convert PC VGA into standard RGB?
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elmagicochrisg
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Re: VGA to RGB

Post by elmagicochrisg »

bacteria wrote:Anyone know a cheap and easy way to convert PC VGA into standard RGB?
Don't you mean the other way around?...

Standard RGB output (e.g. SNES SCART RGB) converted to PC VGA.
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jeffro11
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Re: VGA to RGB

Post by jeffro11 »

Your post is hard to understand but... Just combine the H and V and you get Csync. If you need H and V separated buy an LM1881 IC and it will separate the syncs for you.

To get the combined. You just need to use a 74LS86. Resistor and cap to ground on both H and V going into the chip. Your output will be on pin 11...
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bacteria
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Re: VGA to RGB

Post by bacteria »

elmagicochrisg wrote: Don't you mean the other way around?...

Standard RGB output (e.g. SNES SCART RGB) converted to PC VGA.
Yes, you're right, I do.

If I connected a C-Sync (or composite as that's an alternative to C-Sync) to the V-Sync and also H-Sync lines, would that work or do I need the LM1881?
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jeffro11
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Re: VGA to RGB

Post by jeffro11 »

You will need the LM1881. The timings are different for V and H.
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bacteria
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Re: VGA to RGB

Post by bacteria »

Thanks for the advice, i'll try one out.
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elmagicochrisg
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Re: VGA to RGB

Post by elmagicochrisg »

Image

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