CGA, RGBS and VGA

[tcancian]

EDIT: I'll be posting the progress on my setup, should anyone be interested in trying it out.

Needed:

- ArcadeVGA (searching) (needed to output 320x240)
- SDTV CRT (found, 38" sony wega, accepts 240p through component)
- SCART RGB to YPrPb converter (ordered, yet to arrive) (for TVs outside Europe/SCART zone)
- VGA to SCART cable (waiting for converter) (necessary to connect the arcadevga to the converter)

By the next month I should have some screenshots, i'm also considering buying the Emotia to get badly ported 480i games back to 240p.

So far the only 240p game I tested with the Wega was ICO and it looked amazing, had scanlines and everything. I already ordered SCART cables for SNES and Saturn, will order for PSX and MD/SMS soon enough.

[fagin]

Hi. I'm new to the forums and hope you guys don't mind answering a bunch of questions i've been trying to figure out about old consoles in the last months.

1) Would a GameCube SCART cable work on an american SNES?

I found some diagrams on this website:

http://members.optusnet.com.au/eviltim/ ... escart.htm

Would that 12V stop me from using it at the SNES for some reason? I'm not familiar with SCART.

2) http://cgi.ebay.com/RGBs-EGA-CGA-YUV-15 ... 2c5c706e59

The adapter advertises it is able to receive CGA which i'm assuming is the kind of signal output by SNES, Saturn and other consoles when coupled with a SCART conector. How could I hook up the cable to the adapter? I don't have any soldering skills so i'm not considering modding. Would SCART to DB9 and then DB9 to DB15 work? I did not bought the adaptor yet, and my SNES broke, and all my other consoles are hooked up through VGA or Component, so I have no way of testing this.

3) I read the NES has no RGB unfortunatly and the mod (buying a Play-Choice PPU) is rather expensive. Does buying a nice quality, shielded, composite cable and then a Composite to VGA or maybe Composite to SCART, then connecting it to the adapter above, then to the SLG-3000, increase image quality?

1) Depend on your region of Gamecube as not all have RGB output. Don't worry about the +12v's.
2) See this thread here http://shmups.system11.org/viewtopic.php?f=6&t=35423
3) Nope... you can't polish a turd. Composite is crap.. end of. That is slightly tongue in cheek as you can enhance the signal, but it will cost you a fair bit of cash and you still won't have anything as nice as RGB quality.

[tcancian]

@fagin

Thanks for the link. I took a quick read and doenst sound that much hard. I'll try to get some soldering skills and will give it a shot.

Though at question one I want to use a GameCube SCART cable at the Super Nintendo, not the other way around. But I think it will work safely, I'll try to get a new SNES as soon as possible and test it. I heard many rumors that the NTSC SNES had no RGB output but I saw a comment Play-Asia in which a guy said that all you needed was a GameCube SCART instead of Super Famicom. And I guess according to the schematics he's right.

Thanks for your reply

[antron]

yes, you can use a GC SCART RGB cable on a US SNES.

I use this one:
http://www.play-asia.com/paOS-13-71-24-49-en-70-64.html

[Zapf]

Do note that the quality of these cables can vary, as well as the amount of capacitance they put on the r g and b lines. Some I have seen with 100u caps instead of 220u - this can cause image distortion with very bright screens. Make sure you check your cables if you are having problems like that.

[bryan_c]

Keep in mind that allegedly not all American SNES revisions support RGB out. From what I understand, only the older models do. If you have something newer, unless it's a SNES2 (for which there is a mod to restore RGB), the best you'll be able to get is s-video. Which isn't all that bad, really - it's much better than composite - but RGB is better. Though unfortunately s-video won't work with that CGA-to-VGA scaler without an extra device to transcode s-video to either RGB or component (not composite!); I'm not aware of any cost-effective ways to do so, and I'm assuming if you're considering the CGA scaler that cost is important to you...

If you're adventurous and have the right tools, you could open up your system and compare with the photos on the page describing the S/PDIF mod. If yours looks like the "Older APU module", it should support RGB out. If you have the "Newer onboard APU", RGB might work... I'm having a hard time finding a source of information on this. If you have the "last revision of the APU" (no pic given), your SNES won't support RGB as discovered by kamiboy.

To save you the trouble of cracking it open, look at your eject button. If the word "eject" is written in white, you have one of the early models, and RGB should work. If it's the same colour as the rest of the button, but the text is molded on (that is to say, you can "feel" it) you have a newer model, and RGB may or may not work. If you don't have an eject button at all, you have a SNES2; see above link if you want something better than composite out and are willing to solder.

[tcancian]

Thanks everyone for the replies.

If my new PSU doesnt work I'll look for the white decal Eject button SNES. Thanks a lot, that will sure save me a lot of trouble.

And good news:

Apparently fagin inspired some guys at making an easy hook up solution for the problem of converting SCART/CGA to VGA.

http://bencao74.blogspot.com/2011/02/sy ... rator.html

It will output a 15 khz VGA signal that could be fed on the CGA to VGA adapter to make a 31 khz VGA signal that then could be used on the SLG-3000 to recover scanlines.

Looking forward to that one

I'm not sure if these are the same guys that made the SLG-3000 though...

[ZOM]

They are. There's a thread about it somewhere in this section...

EDIT: Here is something: http://shmups.system11.org/viewtopic.php?f=6&t=35423

[tcancian]

Sorry for rising this thread back from the dead but which setup would be best? I also intend to use it for MAME. The problem is that HDTV CRTs in Brazil do not have RGB/VGA connection for some reason, in the best case scenario, HDMI.

1)SCART -> SCART To YPrPb (Transcoder) -> 480i SDTV CRT

2)SCART -> CGA To VGA -> SLG3000 (maybe) -> VGA To HDMI -> 480p EDTV CRT

3)SCART -> CGA To VGA -> SLG3000 -> 21" CRT Monitor

I heard the first setup would screw the proportions a bit due to NTSC encoding, would the latter not suffer from this issue?

Would the first setup maintain the 15 khz vertical frequency even though it's not an arcade monitor?

[fagin]

As far as I kniow.......

The latter conversion you would lose out slightly on hori line length if you were looking to line double to ideally 720x480, since the output would be 640x480 as a minimum.

I assume if you are transcoding then the frequency on that would stay as 15khz for option 1. It doesn't have to be an arcade monitor as a SDTV CRT will also sync at that rate (or should do).

[wildchild22]

Hi there option 1 is fine for all systems I have rgb modded. And look better than any lcd or plasma in my house. I have also used the cga to vga to a computer monitor and that is good too but the crt sdtv is best.

I have tried
1)pc engine
2)n64
3) nes
4)psx
5)snes
6)dreamcast
7)saturn
8)sega 32x.segacd,sega genesis

9)mame ** for mame I run 320X240p as I have no over scan and I hate the flicker from 640X480i. I use the arcadevga card to get this output. I am going to get a real monitor some day but my crt sdtv with component input using a lossless scart converter is just awesome.

For me I have a iscan duo, cga to vga converter, xrgb-3 (should be here any day), hd box pro(should be here any day, SLG3000, and even with all the latest scalers and so forth the image cannot match my crt's
But the best display I have is actually a nec xg-1352 3 crt projector with 8" tubes weights 150 pounds plus not a paper weight projector.

I am stock piling crt monitors I find at the roadside trash (3 this week). Brought them home works 100% no screen burn. Cannot believe people are throwing them away. At least light guns work with them.

I am tinkering with the latest technologies but they cannot compare to my nec xg-1352 but it is fun to play even though its expensive.

end of rant

[tcancian]

@fagin

I tried a new hookup in order to test 240p on my SDTV CRT and the result were:

No flickering and scanlines! Looked really awesome!! I used ICO for that test. But yeah, just as you said, there was a black horizontal bar on the top of the screen, but after a while I didnt care anymore, there was no tearing, lag and pixels popping out. The setup I used before was ICO -> HD BOX PRO -> 1024x768 FDP Plasma TV and the CRT looks MUCH better.

@wildchild22

Glad you posted that, I was thinking about a way to get MAME to run at 320x240p. So you ordered the ArcadeVGA and then used the 15 khz to Component? What happens when you boot Windows? I heard windows boots at 31 khz, and then the ArcadeVGA kicks in at MAME and it's 15 khz 320x240 again. But isnt there a chance that the 31 khz will pass and damage the equipment?

EDIT:

If I were to use the setup above to play, let's say, Third Strike. That game has 384x224 resolution @60 hz (progressive). Would it work? Or would the converter crop the image since 240p is usually 320x240 or does the horizontal doesnt really matter? In my Plasma HDTV FDP, it accepts 1280x720, even though it's 1024x768 (anamorphic widescreen), a very similar case of having enough vertical lines but not horizontal. What happens then? Would the converter turn that into 480i? Apparently all CPS-1, CPS-2 and CPS-3 (excluding rotated shooters) use such resolution. How would a CRT handle this?

EDIT[2]:

Found this thread at: http://forums.xbox-scene.com/index.php? ... 89343&st=0

According to CospeFogo the only way to present the image without cropping is doing 3x scale (1152x672), and the only resolution with enough pixels to support that is 720p. I assume that would cut off the scanlines right? So... Is there a way of getting real scanlines with 3S at a 4:3 CRT? How do you guys think that 3x scaled with MAME scanline effect would look? Do you guys think that in this situation a widescreen CRT would make the difference? Found this picture of a Third Strike cabinet:

http://www.arcade-museum.com/images/104/1048924447.jpg

According to MAME, in aspect ratio, 384x224 is 12:7. What a mind****. Tips? Or should I just give up?

[fagin]

I'm getting slightly confused here with your last post.........

If you are looking to use a SD CRT with MAME (and a ArcadeVGA card) you have no reason to worry about image cropping etc (unless you want to play weird res vert shooters like Scramble in tate). Your SD CRT will display the resolutions correctly assuming you stick with 15khz.

If you are using a higher resolution screen @ say 640x480 or above, you would need to use the option in MAME to use DIRECT3D and STRETCH USING HARDWARE.

Apologies if I'm getting confused with your requirements.

[wildchild22]

With the newest arcadevga card it outputs 15khz for all screens including boot and windows. It shows up on my sd crt tv with no problems. I run all games at 320X240p presently as I have found native resolutions for example mrs packman is off the screen the top and bottom. I haven't had a lot of time to fool with it lately. Just playing games.

Mame looks great at 320X240p on a crt sd tv. I am using a scart to component video converter from ebay. I just typed in sega scart on ebay and found one. It is a black box made of metal a rip off of the csy I think.

[tcancian]

@fagin

Thanks for replying again. I wanted to do the same setup wildchild22 said below. 320x240p on MAME at a SDTV CRT.

@wildchild22

I'll definitly try that setup! Thanks a lot to both of you.

[fagin]

Don't limit yourself to 320x240 for a SD CRT set-up. Alot of this depends upon your geometry settings available on your chassis granted, but if you have access to hori and vert size / position, you should choose the resolution in MAME that fits the original the best (and alter geometry to suit). This is where an Arcade Monitor pays dividends.

Obviously you can only work with what you have though..... just thought it would be worth mentioning.

[wildchild22]

Yeah all my pic controls are in the service menu which is hard to get in to. That is why I settled on 320X240p till I get a real arcade monitor.

[tcancian]

@fagin

I was aware of that, but still, thanks for the heads-up!

@wildchild22

And how's the picture for CPS-2 and CPS-3 on your setup? I assume Neo-Geo will play flawlessly.

Anyone got experience with this? http://cgi.ebay.com/Arcade-VGA-RGBS-CGA ... 2c5b069f79

It promisses to convert a 31 khz VGA signal to 15 khz RGB (RGBS/CGA) signal. Is that even possible? I mean, isnt 15 khz supposed to be 320x240@60 or 640x480@30? How do you convert 640x480@60 to 320x240@60? Downscaling? How good it would look? Or would it interlace the picture, which would mean probably lots of flickers.

EDIT: Confirmed through: http://www.coin-selector.com/sdp/775010 ... _game.html

The adaptor does 480i, not 240p.

[wildchild22]

keep in mind you can have SD 640X480i @ 60hz and also VGA 640X480p @60hz.
The 60hz is not what changes the 15khz signal it is the Progressive.



Please list a few games I can try for you.
I am happy with all the games I have tried running at 320X240p.

[tcancian]

@wildchild22

Are you able to try and take a picture of Third Strike, Battle Circuit, Super Street Fighter II Turbo and Street Fighter Alpha 2? I would like to see how 386x224 games fare in 320x240.

I already ordered the RGB to Component converter but I still have to find an AGP ArcadeVGA video card.

What troubles me the most right now is that some Dreamcast games apparently don't have RGB like Skies of Arcadia NTSC-U, that game has 31 khz VGA but not 15 khz RGB. I guess I could buy VGA to Component (480p to 480i), but I don't know if it would be worth the investment. Anyone knows of other titles that suffer from this same issue?

You're right about the vertical sync, I made a confusion and really 640x480i @60 hz would equal 30 frames and 15 khz frequency.

Is your CRT capable of 480p?

[wildchild22]

I do not have any of those roms so it willl be a few days!!

My crt is 480i only. For dreamcast just use 15kz scart it is compatibility with all games and is the only option for a standard definition crt.

[tcancian]

Assuming I hook up my PC to a CRT using Component Video from the video card, the signal would be 15 khz but the resolution would still be 640x480. If I used soft15khz, would I be able to get 320x240 over component without having an ArcadeVGA?

[Fudoh]

no. If you have a component output on your graphics card (which is rare already), it's running on a different DAC and is not influenced by Soft15khz which only affects the primary DAC (the VGA output).

[tcancian]

Thanks again for the help Fudoh