N64 Official RGB FRA - Sync on luma

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SegaRally
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N64 Official RGB FRA - Sync on luma

Post by SegaRally »

I have an N64 FRA with official RGB Mod.
If i connect the natif CSYNC signal to the luma pin 7 of the nintendo connector (luma signal) i would be able to use my snes retrogaming cable (wich have sync on luma)?
I would like to do it this way :
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NewSchoolBoxer
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Re: N64 Official RGB FRA - Sync on luma

Post by NewSchoolBoxer »

You mention the rare French console that is supposed to be easy to RGB mod. So we're talking PAL here.
Your cable is pulling luma from pin 7 of the multiout and placing it on pin 20 to use as sync. Official Nintendo cable pulls composite (CVBS) instead so luma is sort of an upgrade.
Sure you can connect CSYNC to pin 7 if you cut the trace to prevent luma from also being connected to pin 7. Your cable will work. This would, however, permanently disable S-Video. Up to you if it's worth it.

I'm with the group that says CSYNC doesn't matter if your cables are high quality, except if you need it specifically, such as for Extron device or to route to a computer monitor or RGB capture card.

I'm confused why the site states:
Wired for sync over luma for NTSC consoles, or as Composite Sync (CSYNC) which is compatible with both NTSC and PAL consoles which have been modified for RGB video.
Like PAL N64 has luma last I checked. Retro Access sells a PAL sync over luma cable.
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Xan
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Re: N64 Official RGB FRA - Sync on luma

Post by Xan »

NewSchoolBoxer wrote:I'm confused why the site states:
Wired for sync over luma for NTSC consoles, or as Composite Sync (CSYNC) which is compatible with both NTSC and PAL consoles which have been modified for RGB video.
Like PAL N64 has luma last I checked. Retro Access sells a PAL sync over luma cable.
I think it's worded that way because PAL systems need a 75ohm resistor to ground and 220µF cap in series on Luma while NTSC would be straight through.
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NewSchoolBoxer
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Re: N64 Official RGB FRA - Sync on luma

Post by NewSchoolBoxer »

Thanks for pointing this out. With your tip I was able to find a source for PAL N64 stating as much and another for PAL SNES. Chroma needs the resistor and smaller 68nF capacitor to make S-Video. So 2 euro in parts and PAL would have been good to go.

The linked discussion of the DC offset on nfggames is wrong and modern video amps allow for a capacitor much smaller than 220µF using built-in signal aspect gain correction.

Now what I'd like to see is a universal Nintendo S-Video cable for NTSC and PAL. Could make it auto detect region with a Zener diode or basic comparator on pulling +12V or csync.
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