(Fixed.) KV25XBR, RGB, Audio, etc.

DanAdamKOF

Kyo's Flame
edit: Basically all working. Couldn't figure out how to route audio through the 34 pin connector but that's OK.



Hi guys. I have a Sony KV25xBR. Currently I'm testing the RGB input by connecting some 20awg standed wire to the socket on a Genesis 2. I'm able to produce a horribly-colored image like this:
522984_803363281825_44409290_34990691_473961972_n.jpg

which looks to me like it's treating the signal as a digital RGB signal.
I tied the Mode Switch pin (21) to +5V and got the same picture.

My connector has the following connections made:
pins 34, 21 and 1 joined (audio select and Mode switch tied to +5V)
Pin 30 to Sync wire (Sync)
Pin 27 to Blue wire (Blue)
Pin 26 to Green wire (Green)
Pin 25 to Red wire (Red)
Pins 3, 7, 8, 9, 10, 13 joined to each other + Ground wire (audio R gnd, audio L gnd, Red gnd, Green gnd, Blue gnd, Sync gnd)

So to detail what I've tried, I tied 21 to +5V but that didn't make a difference in picture. I found an old writeup on interfacing an Atari ST to this monitor, where it said to join pin 29 (Blanking input) to +5V, that sounded wrong but I tried it anyway, and it didn't make a difference (I undid it right afterwards). Curiously, if I insert the Sync wire into Composite out, I get a very washed out full-color image. Playable but very ugly looking.
Here's a picture of it with composite as sync:
399102_803370247865_44409290_34990726_265421264_n.jpg



So the missing link is to take the monitor from thinking it's treating the signal as digital RGB and make it think it's analog... I'm looking at Google searches like crazy, but I'm not finding much about this.

Thanks for any help :)


edit: I've done some more poking around, I've tied 33 (RGB/Normal select) to +5V, no change. I tied 21 and 33 both to +5V, no change. I tried each separately and together tied to ground, no change.
 
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daskrabs

Giga Shock!!
I would try:

Pin 30 to Sync wire (Sync)
Pin 27 to Blue wire (Blue)
Pin 26 to Green wire (Green)
Pin 25 to Red wire (Red)
Pin 1 to +5V Genesis
Pin 11 to Genesis Ground

I think the the issue is you're overthinking it. Should be straight thru for most connections. The grounds you listed are way overboard. Leave the audio alone for testing.
 

DanAdamKOF

Kyo's Flame
I have run across that Amiga txt. No audio hooked up right now. About to try daskrab's idea. FYI I'm using a disassembled floppy cable, just soldering to the pins that would normally crimp to the ribbon cable, very easy to mess with.

I saw that the Genesis 2 RGB cables use some caps and/or resistors, am I hooking this up right and me lacking those components is making my image screwed up?

Thanks btw :)

edit: lol. Hooking up +5V from the TV powers on the Genesis and produces a badly-colored image. Good thinking though.
 
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DanAdamKOF

Kyo's Flame
I don't have those components on-hand, I may just order some proper SCART cables since I'll need them eventually, this experimenting right now is meant to be rapid prototyping for my eventual nice 34 pin cable to SCART female socket.

I do have a PSX SCART cable I got long ago, I think I'm going to hook up my prototype to the SCART socket and see if that gives any hints. I know the PSX/2/3 uses Composite as Sync, so I'm not expecting perfection, far from it.

edit: I did ask about this over on NFG, if you guys can't figure this out hopefully someone there can.
 
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Yodd

Kyo's Flame
On the Genesis, in my experience, the caps aren't 100% necessary (but might be needed depending on your display). However the resistors are needed otherwise you get a very bright and washed out picture. I typically use either 75 or 100 ohm.
 

DanAdamKOF

Kyo's Flame
OK wow, this is totally backwards to how I thought tonight would go:
547664_803416485205_44409290_34990990_472108897_n.jpg

PS2 via SCART RGB cable with composite as sync: works perfectly.
Genesis with almost-as-plain-as-it-gets RGB: bleh.

HEY HELLO PEOPLE GOOGLING ABOUT THE SONY KV-25XBR KV25XBR KV20XBR KV-20XBR RGB 15KHZ 15 KHZ SCART JAPANESE 21 JAMMA TV MONITOR 34 PIN PINOUT IDC CONSOLE PAL 240P 288P 480I 576I H V C SYNC HSYNC VSYNC CSYNC COMPOSITE VERTICAL HORIZONTAL CVBS RAW
(that oughta get a google robot's attention...)

Contrary to what you may have read online, like I had earlier, you CAN use Composite Video as Sync/CSync, on Pin 30 (H. Sync or Composite Sync). That dude on Shmups years ago is wrong or maybe he ran into an edge case that made him make an assumption.

I did not need to wire up any sort of select/switch/enable type things, I just wired up RGBS and GND (to SCART pin 17) to the corresponding SCART pins. Pressed the RGB button to light up the RGB light in front of the TV, and this worked. edit: Oh yeah, pin 34 is on the top left/ on the notch side, pin 1 is on the bottom right. If you forget or something shine a flashlight at the 34 pin jack.


To those of you in the future struggling with Sony 34 pin RGB like I did for so long (much longer than tonight), feel free to contact me or post in this thread. Let's end the confusion.
 
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DanAdamKOF

Kyo's Flame
OK new issue, I cant get audio to come through at all. SCART L/R go to L/R on the 34 pin connector... I linked both audio grounds on the 34pin to each other and to csync gnd, no change. Tried that with the audio select pin connected to 5V, no change (no change either when audio select is on its own). Taking a break for now. Shouldn't there be an audio ground on the SCART cable coming from the PS2? There isn't one.

Funny since I thought audio would be a lot simpler.
 

DanAdamKOF

Kyo's Flame
Yeah so, I just wired some RCA jacks from the SCART plug to feed into a video input, and selecting that input has the audio come in with RGB. I wanted to avoid this since it uses up one composite input on the TV, but I guess it could be worse.

I am currently doing worse at games since I keep staring while playing...
 

DanAdamKOF

Kyo's Flame
HI THREAD

I remade my adapter. This time I wanted audio to come in through the 34 pin connector and I got that working. The key to making this work is linking pin 34 to VCC (pins 1 or 2). Then feed L R and their GNDs to the appropriate pins.

Hmm looking above I apparently tried that before, no clue why it worked this time. All I can really say, I linked the GNDs on the SCART connector to each other, then connected GND to L and R GND from the 34 pin, and connected L and R to L and R input on the 34 pin. And pin 34 to VCC as I said.
 
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DanAdamKOF

Kyo's Flame
The Sony Profeel KX-2501a also uses this same connector. Searching this I ran across a few links with people interfacing to the 34 pin RGB port, possibly some of what's here might be of help:
http://www.theisozone.com/forum/viewtopic.php?f=145&t=60545
http://blog.andyselle.com/2015/06/17/a-rgb-display-for-an-apple-iigs

Also btw there's some NEC monitors (if I remember correctly) that have the same 34 pin connector, the pinout is the same (again, IIRC) so all of this should apply. If I knew the model I'd bomb this with more keywords ;) Meanwhile: Sony Pro Feel
 

faroffmods

Bashful Neophyte
Hi DanAdamKOF

Just bumping this thread to get some activity going. I am looking to either build a 34pin cable from a floppy cable like yours. Or maybe modify an XRGB Framemeister female scart to male 8pin mini din cable to use with the PC-701 RGB adapter. The PC-701 was the RGB adapter made for the KV-25XBR, but it only was built to support Apple III and IBM personal PCs back in the early to mid 80's. I will likely go the PC-107 route first as modifying the XRGB cable should be as simple as moving a few wires around on the 8pin side.

In a perfect world, I would just shell out a good amount of money for a cable. (I'm looking at you SONY!!:mad:) But it seems no one sells them anywhere! Well, If you are looking to make some extra Christmas cash, let me know. I would gladly pay a good price. :D
 
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DanAdamKOF

Kyo's Flame
Nah unfortunately I don't have time to fab up a plug, I'm way too busy with IRL stuff until the new year. If I had time to offer my services I'd love to, I've had actually a fair amount of people ask me to make this for them for cash.

Just to reiterate in this thread what I said in the old thread, for the benefit of whichever lurker might be reading, I do plan to fully pin out the cable I made and provide some instructions so that anyone can follow my steps and have a well-working cable.
 

nakedarthur

New Challenger
Nah unfortunately I don't have time to fab up a plug, I'm way too busy with IRL stuff until the new year. If I had time to offer my services I'd love to, I've had actually a fair amount of people ask me to make this for them for cash.

Just to reiterate in this thread what I said in the old thread, for the benefit of whichever lurker might be reading, I do plan to fully pin out the cable I made and provide some instructions so that anyone can follow my steps and have a well-working cable.

Did you have a chance to test the RGB with more systems? I've heard of some Genesis cables not including all the necessary caps, so I wonder if that could be why it wasn't working.
 

DanAdamKOF

Kyo's Flame
My KV-25XBR still isn't set up but I'm planning to start moving stuff around and set it up kinda soon. I used it with PS2, PSX, SNES, a few PCBs, but I don't remember if I hooked up a Genesis at some point.
 

nakedarthur

New Challenger
My KV-25XBR still isn't set up but I'm planning to start moving stuff around and set it up kinda soon. I used it with PS2, PSX, SNES, a few PCBs, but I don't remember if I hooked up a Genesis at some point.

Nice! Thanks for info. Is the pinout above in first post what you used?
 
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