XRGB-3 and sega saturn

[humbug]

so my mastersystem and megadrive are now working sweet however using the same pins for my saturn, I get a garbled picture... fuzzy static with red green blue dots randomly specled over a sea of grey. I have a feeling it doesn't like the composite sync.

Does anyone know whats going on? I know it works with composite video but I have that feeling im not supposed to use that :S

[brentsg]

Composite is what you'd use if you wanted it to look horrible. But it sounds like you haven't gotten to that yet.

I wouldn't personally use an XRGB anything with less than s-video. Of course an RGB cable is preferred.

[humbug]

Well, i did notice that it looked rather fuzzy overall with composite video used for composite sync...

i have a feeling though that something isn't right with comp sync though...

I am using the RGB/VGA port on "D in 2" by the way.

[SGGG2]

EDIT: Forget about the DIY and get some RGB cables off ebay.

[humbug]

sorry, no can do... the connecter at the saturn end has been chopped

im pulling signals directly off the pcb via a 9pin d-sub. reason for this is so i don't need 50 individual cables for each individual console. I like uniformity... unfortunatly not all consoles were made equal

i guess I could post up a pinout of the board im using... that might be able to tell you if im doing something wrong :/

[humbug]

So i finaly got around to fixing my saturn.

for some retarded reason, it just doesnt want to work with sync... so instead i am using composite video for sync and its working... atleast...

how ever i am having that ghey AFC problem... with the warped top left hand side of the screen... I have AFC up to max before it turns into a garbled mess, however its still slightly warped... and it has a very faint shake left to right in that same region too... pissing me off.

Also, I am getting a sea of fuzz over my colours... does anyone know how to get rid of that?

I was thinking maybe I should short those caps on the RGB lines... would that do anything for me, do you think?

[humbug]

it looks exactly like this but 50% milder

http://www.youtube.com/watch?v=zYXkhi5y ... re=related

[humbug]

V-Sync Lock gives me a black screen (no menu so I guess my monitor doesn't like it)

should I use this?

http://www.national.com/mpf/LM/LM1881.html#Overview

[viletim]

humbug,

Are you using a PAL Saturn?
http://nfggames.com/forum2/index.php?topic=4224.0
I haven't verified this myself, so I can't say if it's accurate. It should be easy enought to test with a multimeter.

Given that the XRGB used a J-21 RGB connection, shouldn't you be using composite video (for sync) anyway?

[humbug]

actualy it is a PAL saturn, but i have it running at 60Hz if thats what you are asking.

I am not using the JP21pin scart, I am using the D in 2 RGB (VGA) input on the back.

I am not using the +5v/+9v pin.

I am not sure what I am supposed to be using as sync anyway... I am currently using composite video as composite sync.

Do I need to take pics and a video tonight?

Thanks for the reply!

[RGB32E]

actualy it is a PAL saturn, but i have it running at 60Hz if thats what you are asking.

I am not using the JP21pin scart, I am using the D in 2 RGB (VGA) input on the back.

I am not using the +5v/+9v pin. I am not sure what I am supposed to be using as sync anyway... I am currently using composite video as composite sync.

Do I need to take pics and a video tonight?

Thanks for the reply!

It sounds like you're connecting +9VDC to pin 13 on the VGA connector! So, on NTSC Saturns, pin 1 is wired to CSYNC, on PAL Saturns, pin 1 is wired to +9VDC. So, if your cable makes a connection between Saturn pin 1 and VGA pin 13, and you are using a PAL Saturn, you're connecting +9VDC to the CSYNC input on the XRGB-3!!!!

Your particular Saturn RGB cable stock may or may NOT have composite video wired.

Have you tried a NTSC Sega Saturn (excuse me if you already stated this )?

Looks like this page needs to be updated similar to the SNES page!!!

http://www.gamesx.com/wiki/doku.php?id=av:saturnav

I've found that CSYNC works better than Composite video (CVBS) when connecting RGB to the XRGB-3. Less picture noise and provides a more stable image. The D2 input allows for switching between YUV, RGBHV, and RGBS(Cv). Experiment with setting the HV and Cv on the XRGB-3. When connecting CSYNC + RGB to the D2 input, I set the D2 mode to RGBHV for better PQ, even though I'm feeding the input RGBS!

[humbug]

just as well i havn't chopped my custom VGA cable yet

you might be right about that one... I'll check with my multimeter and scope it, see if i can find csync.

im all after PQ and I had a niggling that comp video wasn't going to help me there!

Thanks alot for the reply!

looks like i got stereo L R around the wrong way too (T_T)山 FFFUUU

[humbug]

what should the sync line look like on a scope?

also the problem isnt fixed when using b1 mode with vga out. i also noticed that there was a couple vertical lines that was half the width of the rest... what causes this?

[humbug]

would it have anything to do with the fact that I am using a different DC adapter? mine is a multi voltage input with a 12v 1.25A output.

I also tested my megadrive and thats still having the same problems with the shakyness even though its using csync not composite.

or could it be my display?

or is it the xrgb-3s firmware?

[darklegion]

would it have anything to do with the fact that I am using a different DC adapter? mine is a multi voltage input with a 12v 1.25A output.

I also tested my megadrive and thats still having the same problems with the shakyness even though its using csync not composite.

or could it be my display?

or is it the xrgb-3s firmware?

Yeah, I think it might be the adapter. I've always had problems with my XRGB-2 since my original DC adapter died. I originally had a multi voltage adapter with 12V as well, and it had issues with diagonal scrolling lines. I have a second adapter which was supposedly 13.8V, but closer to 15V (because it was unregulated). It didn't have the diagonal lines issue, and I seem to remember it running fine with the saturn in the past. However, the last few times I've used it, I've had the annoying wavy sync issue with the saturn. It even seems to be happening with the PS2 now as well, although to a much lesser extent.

I wish there was a source for the original DC adapter. Perhaps if I were to find a 13.8 V regulated adapter, but I expect they'd be quite expensive. Although perhaps it isn't even a problem with the adapters, and instead some part inside the XRGB-2 has gone bad.

[darklegion]

I've found that CSYNC works better than Composite video (CVBS) when connecting RGB to the XRGB-3. Less picture noise and provides a more stable image.

If this is actually helpful, then what is required to get CSYNC out of a PAL saturn? I figure you can tap into the signal that goes into pin 10 of the CXA1645 chip (according to the datasheet) but does it require a heap of additional components to work as a standard composite sync signal for the XRGB-*? Or does the signal still exist further down the line, and just isn't hooked into the AV port?

[darklegion]

Well I got around to trying my old DC adapter (which appears to put out 13.8V regulated) and the issues with the Saturn's wavy sync are gone . However, in its place are the scrolling diagonal lines that were the reason I bought the second adapter in the first place .I worked around the issue with the PS2 by wiring each video signal with shielded coax, and separated each ground, but it made for one ugly cable. Perhaps a ferrite bead on each end would be enough? Still, it looks a great deal better than before, the image looks quite stable and the bends at the top corners are very minimal, and look pretty much the same as other consoles.