SNES/Famicon PCB Revisions and RGB Video

[Seraphic]

In RGB you'd be looking at 480i. Never bothered with that and neither should you (for 240p content).

Why would it not be 480p when using RGB? Or does it depend if the emulator supports progressive output?
The Game Boy Player does support 480p for example. And a D-Terminal modded for RGB/VGA should allow for 480p then?

[Fudoh]

Terminology RGB refers to RGBs in 480i. You can get VGA from the Cube, but it doesn't look any better than 480p component. Why should it ? Just because the sync signal is differently implemented ?

[Seraphic]

Terminology RGB refers to RGBs in 480i. You can get VGA from the Cube, but it doesn't look any better than 480p component. Why should it ? Just because the sync signal is differently implemented ?

Correct me if I am wrong here, but earlier in this thread you said it would be possible to mod a GC D-Terminal cable to switch between both RGBs (15khz RGB) and RGBHV (31khz VGA). If that case, would not RGBs (480i) and RGBHV (480p) both utilize not only full color range (0-255) color but full chroma sampling as well (4:4:4)? This compared to 480p component which would be 16-235 and 4:2:2. With that in mind, you are saying there would be no improvement in the picture quality between the two?

[Fudoh]

I've tried both. You must not expect better PQ just because the source is RGBHV now. It's still the same encoder. With transcoded component compared to native RGBHV I could not see any difference ON THE SAME processor. With TVs often times the VGA input has better quality than the component input, due to lesser processing involved.

This said, 480p, no matter which color space, still doesn't look great from the Cube.

I'm not sure if the D/A converter honors the luminance range. I could imagine that RGBHV and component both carry the same information.

[Seraphic]

I see.



What about using a SNES/NES emulator and an JP21 cable with a PlayStation 2?
Would you then essentially be able to achieve the same (if not better) picture quality then when using actual NES/SNES hardware with RGB modification/cable?

[Fudoh]

Probably. Why no just use a PC-based emu ? An Intel NUC maybe ?

[Seraphic]

Probably. Why no just use a PC-based emu ? An Intel NUC maybe ?

I guess I would rather relax and play them on my couch and t.v using PS2 rather then in a chair and monitor with PC.

What's an Intel NUC?

[Fudoh]

a NUC (next unit of computing) is a 9cm x 9cm all in-one board from Intel. http://www.intel-nuc.com/

[Seraphic]

For $99 I think the new console Ouya would be a better buy.
It's completely open for development so emulators are a sure bet.

[trap15]

Not really a good choice, since it'll probably have at least 2 frames of input+display lag.

[panzeroceania]

It's interesting, I've been impressed with the gamecube's picture quality playing Wind Waker via D-Terminal Cable > XSelect-D4 > Dell Trinitron CRT. I didn't feel like the Gamecube lacked with 480p. That said the Dreamcast is godlike with it's native RGBHV.

[Seraphic]

How is the picture quality of the XSelect-D4? Is there any degradation? It seems to be discontinued, but might be just what I need as an all in one to VGA.
Would it work well with a PSP (Component), GameCube (seems like it would not work with a D-Terminal modded to VGA as no VGA input), PlayStation 2 (JP21)?
With JP21 cables would RGB 240p/480i ipunt remain RGB or is it converted to YUV at any point before being outputted to VGA?

[Fudoh]

One of the benchmarks I use for the Cube's 480p quality is Hudson's Super Star Soldier remake and I always found the picture to be lacking definition...

Quality of the XSelect-D4 is ace, but it's usually expensive, so you can just get a transcoder from Crescendo Systems instead.

Compatibility of the D4: PSP works, Cube works, doesn't matter if component, D-Terminal or VGA, the D4 takes all three. PS2 works fine via component or D-Terminal. 240p or 480i RGBs input signals are running through the sync processor and are output as 15khz RGBHV. I'm not sure what you want with this kind of signal.

[Seraphic]

Fudoh,

Would there be any point to doing the RGBHV mod to a GameCube D-Terminal cable if one were to find an XSelect-D4?
Or do you think using the D-Terminal cable as is with a XSelect-D4 would produce the same transcoded picture quality?

[Fudoh]

I have both, a direct VGA cable made from a D-Terminal cable and a component cable, and I don't see any difference.

[Seraphic]

I have both, a direct VGA cable made from a D-Terminal cable and a component cable, and I don't see any difference.

Are these two cables you have for the GameCube or for another console and you see no quality difference?

[Fudoh]

Both for Gamecube. One's a D-terminal cable modded for VGA, the other one's an original component cable. Component cable into the XSelect-D4 and VGA output from there compared to VGA directly from the modded cable - no difference I could spot.

[NWrain]

I hope this is an appropriate place for this question. I have a US SNES. I just got an official Super Famicom RGB cable. When I use it with a Sync Strike to my BVM, I do not get a picture. Does anyone know why?

[RGB32E]

The SFC RGB cable is wired for the Japanese specification, not the European specification (SCART).

http://gamesx.com/wiki/doku.php?id=av:japanese_rgb-21

[NWrain]

For some reason I believed that the Sync Strike was compatible with Japanese Scart. Thank you for your help.

[Drakon]

For anyone interested I got rid of my translucent bar in the middle of the screen on my snes mini. Using the built in video encoder I had the bar, I bypassed the built in encoder with a sony cxa2075 application circuit and the bar disappeared. My friend in new york I recommended that he just wire up the rgb from the inputs of the built in encoder and use a rgb amp to get straight rgb. Doing this bypassed the video encoder and he said wiring it that way also got rid of the translucent bar in the middle of the screen. For testing I wired up a sony cxa1645 circuit on the bypassed rgb and the translucent bar came back, but atleast the cxa2075 gets rid of it. The best rgb comes from any model snes that uses the onechip ppu. All snes mini / jr systems have the onechip ppu. To find a model 1 snes with the onechip ppu you need to open your model 1 and check the pcb revision.

[Fudoh]

That's interesting news! Thanks!

If there's any chance you could provide a few close up shots of the mod itself along with a few screenshots, it would certainly be highly appreciated by everyone here bugged with the banding issue !

[Drakon]

That's interesting news! Thanks!

If there's any chance you could provide a few close up shots of the mod itself along with a few screenshots, it would certainly be highly appreciated by everyone here bugged with the banding issue !

Picture of the mod? How would that help? Anyway here's a video comparing the s-video quality between the un-modded 2 ppu model 1 to my snes jr with the cxa2075 circuit installed. I recommend you watch this in 720p:

http://www.youtube.com/watch?v=K8TcINkc7eE

From the cxa2075 snes jr:

http://www.youtube.com/watch?v=skXPiuRQlPY

The screenshots are in the following order:

1: A non modded model 1 snes with the rev 1 ppu
2: A s-video modded model 2 snes with the rev 2 ppu using the built in video encoder
3: A s-video modded model 2 snes with the rev 2 ppu using a sony cxa2075 video encoder









The translucent bar completely disappears when using the cxa2075 encoder, I have no clue why.

[Fudoh]

Picture of the mod? How would that help?

to see what parts are neccessary for the whole circuit except for the actual Sony encoder IC.

[Drakon]

Picture of the mod? How would that help?

to see what parts are neccessary for the whole circuit except for the actual Sony encoder IC.

Taking a picture of the physical circuit won't help with that. I downloaded the cxa2075 datasheet and built the ntsc internal trap application circuit. Then I wired it into the inputs of the built in encoder in the snes jr. Here's a quick schematic:



Schematics make a lot more sense than taking a picture of the physical circuit. The resistors on the luma (y) output and chroma (c) outputs can be tweaked. I can't remember what values I wound up using. Tweaking the chroma line in a snes is very important the snes rgb has interference which I masked by changing the resistance on chroma. If you want just a pure rgb setup you can use either the cxa2075 or just a straight rgb amp. I recommended to a buddy to wire up a ths7314 rgb amp to the same signal inputs and he said it worked great again with no translucent bar.

[Fudoh]

thanks for the additional input!

Have you actually used RGB output from the encoder ? The s-video picture seems a bit oversharpened.

[Drakon]

thanks for the additional input!

Have you actually used RGB output from the encoder ? The s-video picture seems a bit oversharpened.

No I havn't. The whole point of using the cxa2075 is that it produces the sharpest s-video I've ever seen. I wouldn't call it "over sharpened", it looks better than the cxa1645 the sharpness looks amazing. The translucent bar disappearing was an accidental side effect. If I could use the cxa2075 in all of my consoles I probably would. The pc engine the best way to get s-video is right from the built in video circuit. The sega genesis the best possible s-video actually comes from the video circuitry in the 32x (yes I wired up a cxa2075 to my genesis the 32x looks better). And the cxa2075 doesn't seem to like arcade rgb I get flickering going on.

However for both the snes and rgb modded nes the cxa2075 works perfectly.

[Fudoh]

I see quite some artefacts, especially jailbars in the third picture (from the 2nd set), which are likely caused by emphasizing the luma channel. In my opinion (don't take it personal, the 2nd picture looks much better). Nevertheless, thanks a lot for the concept and I hope to able to try the CXA2075 with RGB output sometime. The lack of visible banding is a huge plus in my book.

[Drakon]

I see quite some artefacts, especially jailbars in the third picture (from the 2nd set), which are likely caused by emphasizing the luma channel. In my opinion (don't take it personal, the 2nd picture looks much better). Nevertheless, thanks a lot for the concept and I hope to able to try the CXA2075 with RGB output sometime. The lack of visible banding is a huge plus in my book.

Snes rgb always has video "artifacts". The built in encoder is just so blurry it's not as visible. Anytime you use a better encoder that produces a sharper image these artifacts become more obvious. Luckily none of this shows up at all on my tv it's just my capture card picks up everything. I don't take it personally but once again....my youtube capture:

http://www.youtube.com/watch?v=skXPiuRQlPY

No artifacts in the video.

Any interference I pick up with the cxa2075 is also there using the encoder built into the snes jr. The problem isn't the encoder, it's built into the video signals right from the ppu.

Also as I mentioned before if you're just using rgb then instead of using a cxa2075 just wire up a ths7314 rgb amp to the same tap points that I use for my circuit. I only use the cxa2075 because I'm using s-video. The cxa2075 is sort of an all-in-one package it amps the rgb, and generates s-video (also composite video but I don't bother using that). The cxa2075 is a great solution for people who want s-video without that annoying translucent bar.

[Seraphic]

Have the lowest and highest serial numbers been established to a point that they can be used to insure a SNES with serial numbers above the lowest serial number and below the highest serial number will be a 1Chip SNES? Also, based on what I have be reading, seems SNES's that were made around 1995 have the 1Chip. Does the Copyright on the bottom of the console say copyright 1995 as well or do all NA SNES's say copyright 1991?