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Thread: Composite weirdness out of a 60Hz modded 32x

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    Master of Shinobi
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    Default Composite weirdness out of a 60Hz modded 32x

    I usually run my games in RGB, but out of interest I thought I'd see how composite looked out of my Framemeister, taking the composite from the jacks in my SCART splitter. Weird is the answer. The 50/60Hz switch had an effect on the colours, but with the Mega Drive outputting 50Hz the image was a total mess; flashing coloured bands everywhere. Interestingly, switching the MD and 32x to the 60Hz position produced a much better picture. It still suffered from some odd colour glitches, but on the whole was a lot more stable. Composite output direct from the MD was fine.

    Here's where it gets a bit stranger: plugging the 32x into the composite input of the TV, rather than the Framemesiter, works fine too. Admittedly I used a different phono cable to connect to it, but I don't think that should have made a difference.

    Can anyone suggest a reason for the weird result on the Framemeister? Flawed workmanship on the mod (though it was so simple I can't think what could have gone wrong)? The mod itself is flawed? Other?

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    Creator of the Mega Amp Raging in the Streets Ace's Avatar
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    The XRGB-Mini has major oddities with Composite out of a MegaDrive and MegaDrive hardware clones. The biggest issue I found is wild inconsistencies with how the XRGB-Mini produces color every time the converter syncs to the video signal going into it. One minute, you could have perfect colors, but when you shut off the console and turn it back on again, you get a noticeable hue shift, either on the entire image or on specific colors. This also happens with S-Video if you have an S-Video modded system or a hardware clone with native S-Video output, though it's not as pronounced as it is over Composite. For me personally, this is a huge problem as it makes my life a lot more difficult when I have to do any recording for my clone console comparisons on a hardware clone. Due to this color inconsistency issue, I have to get through every game I use to test uninterrupted on a flash cartridge because every time I have to shut off the system to swap out a game, I get different colors every single time, and the recent dbElectronics article regarding misuse of 3.3V hardware in such cartridges just made things even more difficult for me.
    With regards to the 32X, you really don't want to have the 32X and MegaDrive at different frequencies. Set both to 50Hz or 60Hz, but don't set the 32X to one frequency and the MegaDrive to another.
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    Quote Originally Posted by Ace View Post
    Set both to 50Hz or 60Hz, but don't set the 32X to one frequency and the MegaDrive to another.
    Generally they are, but the only difference the 32x switch made on its own in this case was colour tone. The main impact was caused by switching both to 60Hz, but even then the Framemeister would intermittently lose sync. Ah well, it doesn't really matter too much; I normally play using RGB, and that works fine.

    FWIW, I've had no such problems with the Framemeister and my 3DO.

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    Creator of the Mega Amp Raging in the Streets Ace's Avatar
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    It's only with the Genesis that the XRGB-Mini falls flat on its face with regards to Composite and S-Video discoloration. It does have some sync issues with some particular MSX computers (Sanyo Wavy2, specifically, in my case, which sometimes has a rolling picture), the Mark III's Composite output (heavy jitter and lots of signal dropout) and the Japanese Master System's Composite output (it can hardly sync to this one, though I would probably attribute it to low voltage on the Composite output itself). Anything else I put over Composite or S-Video is fine; NES (including hardware clones), Super NES (also including hardware clones), Nintendo 64, Philips VG-8020 MSX computer (including an S-Video modded one), 3DO, you name it, it works.
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    urusei yatsura Master of Shinobi lumclaw's Avatar
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    Did you add an NTSC xtal to the 32x? Megadrive and 32x aren't really what you'd call "designed" for PAL60.

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    Quote Originally Posted by lumclaw View Post
    Did you add an NTSC xtal to the 32x? Megadrive and 32x aren't really what you'd call "designed" for PAL60.
    No. Though you raise a fair point, the system is running out of spec, it actually seems to work worse in 50Hz than 60.

    While this isn't a big deal as I don't usually output in composite, I have to say that the Framemeister is not exactly impressing me in general these days. Its super slow syncing when a console changes resolution, and the fact that it doesn't seem to properly detect interlaced modes on modded consoles without changing the sync mode (with no manual override), are really beginning to get on my nerves; they're significant problems when running a Saturn or Playstation. If I had more money at the moment I'd be tempted to try an OSSC.

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    urusei yatsura Master of Shinobi lumclaw's Avatar
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    Yeah for all their convenience (who wants to waste space to hook up 2 or 3 versions of systems?), modded consoles can be riskier.
    It's not the responsibility of TVs or other devices to support them, nor is it practical with all the variations different modders might try.

    I've still got my apparently bricked Framemeister around. Haven't felt up to diagnosing it, lacking better ideas I'd suspect a power outage.

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    Hmm, maybe, but I don't think it's unreasonable for a fairly expensive device intended to be used with a variety of hardware to be able to accept arbitrary input refresh rates within a certain range. The Framemeister does seem to support the inputs, it just fails to properly process mode changes without being given a kick. Even when fed a signal that's in-spec, the mode switching is so slow that it's pretty much unfit for purpose for some games on the 32-bit consoles. At the very least, it would have been beneficial if Micomsoft could have added an option to force how the input video signal is handled. The irony here is that it looks ugly as hell when it incorrectly treats 480i signals as 240p, but that mode switching delay is eliminated.

    Anyway, that's just me venting. It shouldn't have much to do with the problem with the composite signal at 50Hz.

    As for the composite problem, this is one of those times where I wish I had an oscilloscope to get a more accurate impression of the signal my 32x is putting out. I might open my 32x up again and examine the mod, or I might just ignore it as I use RGB anyway.

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