So.... Some SNESes output YPbPr.....

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Drakon
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Re: So.... Some SNESes output YPbPr.....

Post by Drakon »

I included in that zip a picture of the pinout of the later encoders like the 6595 / 6596. Those pinouts seem to have been manually figured out and not taken from any data sheet but I've wired up those encoders myself and they're correct. The 6595 / 6596 don't have component pins according to the pinout but the 6592 does...so your guess is as good as mine.
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Re: So.... Some SNESes output YPbPr.....

Post by Ziggy »

Well the 6594 is still branded "S-ENC" and not "S-RGB" like the later ones, so I think there's a good chance. That, and I was checking out the pins with a multimeter yesterday, ground is in the same spot as the 9562 (which is clearly different from the S-RGB). And just from looking at it, the traces on the mobo seem to be the same to the 6592 that some one did the mod on and posted here.

So I'm 99% sure that the 6594 also has component out. I was gonna check yesterday but got sidetracked with a bunch of other stuff. I'm gonna try my best to do it today. I'm just so curious.
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Re: So.... Some SNESes output YPbPr.....

Post by Hobie-wan »

So I only skimmed the Sega-16 thread, but they're talking about early/launch units, then one guy shows he modded his successfully but it is a later model because it doesn't have a separate sounds module.

http://www.sega-16.com/forum/showthread ... post476496
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Re: So.... Some SNESes output YPbPr.....

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Yeah, I was a little confused too. Here's what I've noticed: That guy that you linked, his board is stamped 1992, so we know it's that early. You can see his SNES is yellowed, and it doesn't have a sticker by the power button (though it could have been removed).

In addition to this, I was noticing which models have the sticker by the power button (turn off power before ejecting) and which models have the locking mechanism inside. I thought earlier models had the lock, but I have two SNESes now with the 6594 encoder and no lock. So did they add that slider lock thing later on? More over, the two SNESes that I have with the 6594 encoders aren't yellowed at all, they look great.

So one would assume the 6492/S-ENC encoders were used in the very first models, but that would mean the separate sound module thing wasn't in the first models. And again, that would mean that the earlier SNESes didn't have the cart lock thing. Another thing I've noticed is that those guys encoders are marked "S-ENC" with no actual model number. Are we just assuming that they're the 6592?

I think we're busting some myths here. If the earliest SNES had the S-ENC (6592) encoder, then the earliest SNESes didn't have the separate sound module. Looks like they switched to the 6594 encoder for a while, then started the separate sound module, then took it out possibly when they started using the S-RGB encoder.

Out of my three SNESes that I currently own:

SNES 1:
Purchased in 92 or 93 for sure, mobo is stamped 93. Has yellowed. Has 6594 encoder located back by the AV port. Has separate sound module. Has cart lock mechanism.

SNES 2: Date purchased is unknown, mobo is stamped 93. Has not yellowed. Has 6594 encoder located in front of the cart slot. Does not have separate sound module. Does not have cart lock.

SNES 3: Date purchased is unknown, I forgot to check the date stamp on the mobo. Has not yellowed. Has 6594 encoder in front of cart slot. IIRC, it also does not have a separate sound moduel. Also does not have cart lock.
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Re: So.... Some SNESes output YPbPr.....

Post by Ziggy »

CONFIRMED

The "S-ENC B" BA6594AF encoder outputs component video!

Image

Image

I did a real rush job and just tacked all the wires on, and I haven't really tested yet (just to see that it actually works), but it looks good! As far as I can tell, it's better than S-Video on the same system and TV.

So since this encoder outputs component as well, that means a great many SNESes out there can output component directly! I can't believe this info hasn't been discovered until now. :lol:

In case any one is wondering, here's a "stupid-proof" pinout for the S-ENC:

Pin 1 = Component RED
Pin 23 = Component GREEN
Pin 24 = Component BLUE

I'll most definitely be doing a more permanent version of this mod to my SNESes, first I gotta get the appropriate color RCA mounts (I only have white and reds on hand). After that, I'll post back more results including comparing the quality to S-Video and composite.

Some one should try and locate a supplier/retailer for these encoders, they'd be great to have! There was talk on that Sega-16 forum about ripping them out of a SNES and using them for a Sega console... :evil:
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Re: So.... Some SNESes output YPbPr.....

Post by Zing »

If only this somehow eliminated the vertical bar, I would definitely do it to my Super NES. I haven't opened it, but it is the original version with the sound module (can feel it via the weight).
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Re: So.... Some SNESes output YPbPr.....

Post by Ziggy »

I'm trying to get the timeline of the console's revisions straight, but it's getting confusing! I'm trying to figure out when the cart lock mechanism was taking out (or put in?) in relations to other revisions like the sound chips, the video encoders, etc.


Zing wrote:If only this somehow eliminated the vertical bar, I would definitely do it to my Super NES. I haven't opened it, but it is the original version with the sound module (can feel it via the weight).


IIRC, people reported seeing the line even when outputting RGB, right? So if that's the case, the line will probably be there with the component output as well. Unless there's some magic involved.

Unless you're already using RGB out, I would definitely suggest doing this mod. Like I've said, I haven't done any thorough testing yet, but a quick check looks like component is a better picture than S-Video.

When I get the correct colored jacks in and redo this mod, I'll do some hardcore testing. I'll get comparison pics for everyone, if I can, and I'll check for the vertical line too.
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Re: So.... Some SNESes output YPbPr.....

Post by Ziggy »

So here's a good question...

The S-ENC does not output RGB. No one here in NTSC-U land would have noticed this back when, and only in recent years have people been trying to use RGB to component converters for their retro systems. So does the PAL SNES or SFC have the S-ENC encoder? I only have one PAL SNES, and it's a later model with the combined PPU so it naturally has the S-RGB encoder. But did early PAL models have the 6592 or 6594 S-ENC? I'm guessing they might have had a different encoder that was able to output RGB. Or maybe they always had the S-RGB?

I don't keep up much with the PAL counterparts being that it doesn't really concern me, but I'm sure it would be a pretty well known thing if early PAL SNESes couldn't output RGB. Right? I'm guessing that Nintendo used a different encoder for the PAL SNES, and possibly the SFC as well (Japan uses RGB, right?) unless they always just had the S-RGB. So the NTSC-U SNES used one encoder, the PAL SNES and SFC used another. Then eventually, Nintendo just used the S-RGB in all versions of the SNES. Well, at least that's what I'm speculating.

I'm also guessing that the the ENC might standard for encoder, possibly SNES ENCoder. Then later, S-RGB, as in SNES RGB. Because previously, the video encoder did not output RGB, so that would be a cleaver name for the new encoder.

Anyways, what I'm getting at is, only early and mid NTSC-U SNESes had the S-ENC encoders. It wouldn't make sense for a PAL SNES to have that encoder since they don't use component video there, right? I guess Nintendo figured they shouldn't bother using the S-ENC if there really weren't any TVs around with component inputs, and it might have been easier to just use one video encoder in all versions of the console (assuming they used different encoders depending on the region).

I can't believe this info didn't pop up until 2012. :lol: I wonder if any one ever got an RGB to component converter and wondered why it wasn't working on their SNES. I guess they didn't post for help anywhere.

Bah, I'm ranting. I'm just really excited about this. I can't believe a retro console outputs component video. And the SNES is my favorite retro console!

Jam is gonna work this component out mod into his SNES, and he's gonna end up with the holy grail of SNESes. He already has done the digital audio mod, and he has region switches on it (I was trying to talk him into upgrading that to the switchless "mod chip" version) and now it will have component output. That's gonna be one monster of a SNES.
Last edited by Ziggy on Tue May 08, 2012 8:01 pm, edited 1 time in total.
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Re: So.... Some SNESes output YPbPr.....

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Basically there's two generations of video encoders in the snes consoles. The first generation is labelled as s-enc. The second generation is labelled as s-rgb. They probably changed the labels because the pinout changed. Both generations of encoders are made by rohm. As for the slider locking thing I've only found that inside of japanese super famicoms from my memory.

Also just because your snes doesn't have the separate sound module doesn't mean that it has a different video encoder than the ones that have a separate sound module. They don't upgrade everything at the same time in the systems you know.

And I discovered this information a while ago I honestly just didn't care. The vertical bar has nothing to do with the video encoder it comes from the ppu chip itself. The snes jr is vertical bar free, and outputs a much sharper rgb image from the ppu chip. Also there's more modern analog video encoders / circuits that convert rgb to component than these old chips.

And you're correct the s-enc encoders don't output rgb the rgb from the ppu goes through a transistor amp then gets sent to the multi av port as well as the video encoder inputs. That zip I sent you contains an early snes schematic that clearly shows this. The japanese sfc has the same encoder as the american snes. Really when you have a video encoder that outputs rgb all the encoder is doing is amping the rgb. Some encoders don't even amp the rgb so they literally accept the rgb and output it with the colour encoding range that the encoder is capable of. You don't need an encoder to get the rgb acceptable really a transistor amp is all you need if you want rgb.

The rgb in a console isn't generated by the video encoder it's generated by the ppu / vdp / whatever you want to call it custom graphics chip. The video encoder then takes the rgb, some encoders amp the rgb, some don't so in that case the pcb will contain a video amp. The function of the video encoder is just to convert the video signal into different formats, that's why it's called a video encoder. The sony cxa1145, cxa1645 and cxa2075 encoders automatically amp the signal to the right strength which is great (except on arcade boards they go crazy). Anyway the point is you don't need a video encoder to output rgb to get rgb to the av port for a tv / external encoder. It's actually better that the early model snes / sfc has the rgb go through an amp instead of an encoder because encoders always have limited pallette ranges. I've used a variety of different video encoders and certain encoders are able to generate a larger range of colours. And if you pass a rgb signal through an encoder with a limited colour range the outputted rgb will be limited by the encoder. This's why I bypass console encoders completely when I install my own encoders. This results in a better colour range and sometimes even better image quality.

Early video encoders worked in a strange way. These early chips would first convert the rgb to some other format, output that format on certain pins, sometimes require you to build a small circuit, then the output of that circuit would input into other pins of the encoder, and the encoder would then convert the partially converted signal into composite video. It seems silly but this's how early encoders were capable of getting composite video. As I mentioned before the sony cxa1145 does the exact same thing. The cxa1145 outputs s-video, then inputs the s-video into other pins on the chip, and from there turns the s-video into composite video. The cxa1145 is a really old chip and tvs didn't accept s-video until 1987ish so maybe when the cxa1145 was designed tvs didn't accept s-video. I read that the cxa1145 was found in the sega master system and that system came out in 1986 so that's why the s-video pins on that encoder weren't intended to be used, TVs in 1986 didn't accept s-video. Quite possibly the chips at the time weren't able to contain all the circuitry. When these early rohm encoders found in the snes were made I'm pretty sure tvs didn't accept component video. The old rohm snes encoders are really early encoders so I'm guessing they weren't able to fit all the circuitry inside of the encoder which is why part of the video circuit is external. It's just interesting luck that the partially converted video format of these old rohm encoders is compatible component video.

The later analog encoders that showed up around the mid 90s were more advanced and were able to fit all the circuitry inside the chip. So these later encoders didn't need to output a half converted video signal and input it into other pins on the chip. That's why the later encoders only output rgb, s-video, and composite video. When these newer encoders came out (ba6595/6, bh7236af, cxa1645 / 2075) tvs still didn't accept component video. Therefore these newer analog encoders outputted all the formats that tvs would accept at the time which was just rgb / s-video / composite video.

I'm pretty sure that pal models of the snes also included these encoders. I'm pretty sure pal countries also had composite video and the video encoder takes the rgb and converts it to composite video. Without the video encoder you can't get other video formats besides what the ppu outputs. Your whole theory about pal countries not using the s-enc is silly because the s-enc wasn't installed in the snes for the sake of generating component video for a tv. The s-enc as well as other encoders in the snes were used just to generate s-video and composite video, rgb could either be taken from the ppu or a video encoder that outputs rgb. As I mentioned tvs didn't accept component video back in the days of the snes.

Nintendo as well as any other console company changed video encoders because newer models of video encoders came out. These newer encoders generated sharper image quality and a broader colour pallette range. If nintendo installed the s-enc encoder with the idea of being able to use it for component video then nintendo would have wired those component video pins into a connector on the console. The s-enc was never intended to be used for component video. Just as how the first models of the sega genesis contained an encoder that generated s-video but the s-video was never wired up. The cxa1145 was never intended to be used for s-video. The cxa1145 was probably never designed to have the s-video go to a tv. God knows why these old chips output future formats on certain pins only to re-input them in other pins, but they were never wired up to any connector because they weren't intended to be used.

External rgb to component converters do work on a snes, I don't know what you're smoking.

Really the ultimate in pixel perfect component video quality will probably come from a snes model 2 with the rgb bypassing the built in encoder going directly into a good rgb to component video encoding circuit. This is because the snes jr ppu outputs a better quality rgb image from the ppu than the older models. So tricking out an older model snes is a waste of time. I installed a cxa2075 circuit into an older model snes and my snes jr both bypassing the built in encoders. The s-video from the cxa2075 looks way sharper when wired into the snes jr. because the rgb from the ppu is greatly improved (newer model of the ppu which is greatly improved). From my experience the cxa2075 is the best analog encoder for creating s-video. Using component video will be the same story. Two things determine video quality, 1: the quality of the rgb from the ppu (the source that generates the image), and 2: the quality of your video encoding circuit that converts the rgb into something your tv will accept. All the older models of the snes that I tinkered with had terrible quality rgb coming right out of the ppu.

Also region switches on a snes is cute but you can just use a powerpak or flash cart to play a patched rom so you can you play foreign games. Heck some newer flash carts automatically fool the rom into thinking it's running in the correct region so there's no need to patch.
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Re: So.... Some SNESes output YPbPr.....

Post by Ziggy »

I didn't really need a lesson in video encoders. I'm just trying to figure out the order of the revisions. I didn't realize that schematic had the S-ENC in it, when I looked at it quick I didn't realize the pins weren't in order. I took a quick glance and thought it was the S-RGB. So RGB gets sent to the AV out but not through the encoder, that makes perfect sense.

I realize that all the revisions didn't happen at once, that's what I'm getting at (if you look at a couple of my posts back, I stated that I have three SNESes with the S-ENC B but only one has the separate sound module). I'm trying to figure out the order of the revisions so we can better understand which SNES will have the S-ENC and which ones will have the S-RGB.

I know you've said the SNES mini with the CXA2075 will yield the best results, so you have no interest in this, but the S-ENC outputting component is good news to many of us. I don't use a mini, and I don't plan on using one. I also just straight up don't have the desire to sub in the CXA2075. Getting component from the S-ENC is such a simple mod to do. It's like $5 in parts and 4 wires to solder, it can't get any easier than that. And since I really don't care to built, buy or even use an external RGB to component converter, this seems like the best bet. I don't think it's a waste of time at all.

As for the region switches... I'm all for flash carts. I love them. The Sd2Snes is looking great! But pretty much every one on this forum is into collecting over using flash carts. For that reason, region switches are kind of important. And now that we've got the SuperCIC, we don't even need the switches.
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