Modding Gamecube component cable

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RebeL9
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Modding Gamecube component cable

Post by RebeL9 »

Apparently the DAC in the OEM Gamecube component cablea has a YPbPr>RGBHV transcoder on the chip, unused but present but it requires a mod to get RGBHV working out of it.
Anyone know how this mod is carried out?
I have a Sony HDM-3830 and when trying to connect my Gamecube directly to the monitor through the component cables the image wonky and doesn’t display full screen. The monitor supports 480p.
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bobrocks95
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Re: Modding Gamecube component cable

Post by bobrocks95 »

If you're going to hack it up, I would suggest selling the cable for ~$250, then buying a Carby and an HDMI to VGA converter for less than $100.
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Guspaz
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Re: Modding Gamecube component cable

Post by Guspaz »

If the input is wonky using YPbPr, what makes you think it'll look right with RGBHV? The video timings will be identical and this is an monitor from 1991, long before the standards for video past 480i were well established.

Rather than destroying a rare and expensive active component cable, I'd suggest either getting a YPbPr to RGBHV converter or taking Bob's suggestion and just replacing it with a Carby and HDMI-to-VGA converter. It'll be much cheaper, and if it fails, you won't have destroyed the expensive rare cable.
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maxtherabbit
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Re: Modding Gamecube component cable

Post by maxtherabbit »

The mod involves lifting a pin on the CMPV-DOL chip and can be done in a totally non-destructive and reversible manner. But the trick for comp cables (as opposed to d-terminal ones) is you then need to attach two additional wires for H and V sync.

https://gamesx.com/wiki/doku.php?id=av: ... odigitalav
PC Engine Fan X!
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Re: Modding Gamecube component cable

Post by PC Engine Fan X! »

I have a Japanese Gamecube D-Terminal cable that was modified with a VGA plug (the D-Terminal interface plug was disregarded) -- works like a charm if fed into a HDTV with VGA input with my USA region GC console. I bought it off of eBay sometime back & it was easily north of $200 usd (this was during the time of 1st party Nintendo branded GC component video cables were selling in the $220-$230 range back in the day).

What's intersting is both the 1st party made GC component video/d-terminal cables can be modded to output either at 15.7kHz or 31kHz.

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RebeL9
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Re: Modding Gamecube component cable

Post by RebeL9 »

PC Engine Fan X! wrote:I have a Japanese Gamecube D-Terminal cable that was modified with a VGA plug (the D-Terminal interface plug was disregarded) -- works like a charm if fed into a HDTV with VGA input with my USA region GC console. I bought it off of eBay sometime back & it was easily north of $200 usd (this was during the time of 1st party Nintendo branded GC component video cables were selling in the $220-$230 range back in the day).

What's intersting is both the 1st party made GC component video/d-terminal cables can be modded to output either at 15.7kHz or 31kHz.

PC Engine Fan X! ^_~

How did you mod it?
Was it difficult?
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Guspaz
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Re: Modding Gamecube component cable

Post by Guspaz »

PC Engine Fan X! wrote:What's intersting is both the 1st party made GC component video/d-terminal cables can be modded to output either at 15.7kHz or 31kHz.
No mod is required, those are the cable's native refresh rates to begin with.
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Re: Modding Gamecube component cable

Post by PC Engine Fan X! »

I bought the JPN region GC D-Terminal cable already modded from the get-go. You can buy a GC D-T cable + a D-T to component video adapter for a fraction of the price of a 1st-party GC component video cable right now on ebay.

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Link83
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Re: Modding Gamecube component cable

Post by Link83 »

maxtherabbit wrote:The mod involves lifting a pin on the CMPV-DOL chip and can be done in a totally non-destructive and reversible manner. But the trick for comp cables (as opposed to d-terminal ones) is you then need to attach two additional wires for H and V sync.

https://gamesx.com/wiki/doku.php?id=av: ... odigitalav
Actually from what I recall the H and V sync pins are not connected on the D-Terminal cable either, but the D-Terminal cables have extra wires inside the cable (when compared to the Component cables) as D-Terminal uses these 'data lines' to determine the resolution/signal type. These extra wires can be repurposed as H and V Sync wires allowing you to re-use the original cable for the VGA mod if so desired. The actual mod is detailed here:-
https://gamesx.com/wiki/doku.php?id=av:gamecube_rgb

However as already mentioned, I strongly recommend nobody perform this mod on an original Component cable nowadays given their rarity/cost. If you absolutely must use an original cable then at least use an original D-Terminal cable instead - since D-Terminal is much less well supported worldwide compared to Component video, and they already have extra wires inside the cable which can be repurposed for H and V sync.

Another option would be to get one of the original cables that were converted into RGB SCART cables for Europeans who imported NTSC GameCube consoles 'back in the day':-
https://mmmonkey.co.uk/ntsc-gamecube-rgb-cable/
I still see these pop up on ebay from time to time. Since these RGB SCART modified cables are of much more limited use nowadays due to lacking 480p support (They use the Analog AV ports Composite video signal for sync) plus they have already been pre-modded long ago. In fact I have one of these modded cables somewhere, and (if I can find it) I would gladly swap it for an unmodified original Component cable.
Last edited by Link83 on Sun May 28, 2023 11:16 pm, edited 6 times in total.
RebeL9
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Re: Modding Gamecube component cable

Post by RebeL9 »

Is it this cable you are referring to?
https://www.ebay.com/itm/165092734680?m ... media=COPY
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Link83
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Re: Modding Gamecube component cable

Post by Link83 »

RebeL9 wrote:Is it this cable you are referring to?
https://www.ebay.com/itm/165092734680?m ... media=COPY
Yes, although on the one you linked they have actually removed the original cable entirely, including the original strain relief and ferrite core :?

Here is an example of a completed listing for one that re-used the original cable:-
https://www.ebay.co.uk/itm/225452229953?orig_cvip=true
strayan
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Re: Modding Gamecube component cable

Post by strayan »

RebeL9 wrote:Is it this cable you are referring to?
https://www.ebay.com/itm/165092734680?m ... media=COPY
Honestly if you’re interested in that you may as well buy a Carby and pair with with a HDMI to RGBHV cable like this https://www.amazon.com.au/Snowkids-Non- ... B097QWP33X and a RGBHV to SCART adapter like: https://etim.net.au/shop/shop.php?crn=2 ... how_detail

Note: you will need to power the HDMI to RGBHV cable somehow like by plugging it into (say) a usb powered HDMI switch or splitter.
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Gara
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Re: Modding Gamecube component cable

Post by Gara »

You have me all curious. What's the thinking on changing the Gamecube signal to RGBHV that will make it display a more full screen image? Is it that the HDM-3800 just handles RGBHV differently from YPbPr?

If all else fails I wonder if this is a situation you'd be better off using a video processor for. I remember people used to use stuff like a DVDO VP30 with BVM F24's. I hope you're able to find an ideal solution. It's neat to hear details about such a rare monitor.
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matt
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Re: Modding Gamecube component cable

Post by matt »

I have one of these modded cables. I built it with a switch to select between VGA and YPbPr. On a monitor that supports both video formats, the picture geometry is identical either way. I doubt you'll get an improvement on your HDM by doing the mod.

But I modded the cable 20 years ago when I bought the cable new from Nintendo for $30. I wouldn't do it now.
PC Engine Fan X!
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Re: Modding Gamecube component cable

Post by PC Engine Fan X! »

Here's an ebay auction for a 1st-party Nintendo Gamecube Scart cable DOL-013 EUR: https://www.ebay.co.uk/itm/166127986129 ... R_TUwtqNYg

I didn't know that Nintendo sold such an official Gamecube scart cable for use in Europe...fascinating nevertheless.

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Link83
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Re: Modding Gamecube component cable

Post by Link83 »

PC Engine Fan X! wrote:Here's an ebay auction for a 1st-party Nintendo Gamecube Scart cable DOL-013 EUR: https://www.ebay.co.uk/itm/166127986129 ... R_TUwtqNYg

I didn't know that Nintendo sold such an official Gamecube scart cable for use in Europe...fascinating nevertheless.

PC Engine Fan X! ^_~
Thats the official RGB SCART cable and is only compatible with PAL GameCube consoles since they support 15kHz RGB output on the Analog AV port. NTSC GameCube consoles supported S-Video output on the Analog AV port instead (Nintendo used different video encoder chips for each region)
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Guspaz
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Re: Modding Gamecube component cable

Post by Guspaz »

Notably the NTSC and PAL gamecubes both support NTSC and PAL timings, so a relatively common thing is to use a PAL gamecube with NTSC games to get 240p/360p/480i RGB output without any modding or expensive cables. 360p is for GBI with the Game Boy Player, if you're wondering, as the OSSC and RT5X have special support for GBI's 360p output mode.
ldeveraux
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Re: Modding Gamecube component cable

Post by ldeveraux »

Guspaz wrote:Notably the NTSC and PAL gamecubes both support NTSC and PAL timings, so a relatively common thing is to use a PAL gamecube with NTSC games to get 240p/360p/480i RGB output without any modding or expensive cables. 360p is for GBI with the Game Boy Player, if you're wondering, as the OSSC and RT5X have special support for GBI's 360p output mode.
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