Idea: video/audio capture from edge connector

[YesAffinity]

Hi all, I created a device for my jamma cabinet that captured video and audio, basically splicing the RGB and L/R lines of a JAMMA connector, and taking the lines to a board that converted the signals to either s-video or RCA for the video signal, and RCA-type connectors for the audio.  I could then take the output from the a/v board to a PC USB capture device.

I'm wondering if a similar thing could be done using the unused edge connector of a DK board.  I am not clear if the edge connector is actually functional on a DK board, though.  In theory, you would simply get a female edge connector to connect to the unused connector on the board, connect the appropriate lines to a a/v board like I mention above, and could then get clean game a/v without having to use a webcam, camcorder, etc. to video your arcade gameplay.

If the edge connector can be used in this fashion, does such a device already exist?

Thoughts?

[f_symbols]

I do not know if said device exists, but I can tell you that Richie once had a cab running dual monitors at his arcade, they were both wired to the same pcb, and there was no discernible delay.  Also, the edge connector definitely works, as you can run the PCB entirely from it, however I'm not sure about concurrent signals (ie. the edge connector and the harness connector at the same time..).  This would be sweet for sure

[xelnia]

  loves it, I reckon.

[ChrisP]

Ethan, when you say "cab", do you mean Richie accomplished that with a DK cab?

Anyway, yes, the DK edge connector is very much functional (I am using it now with an adapter that the 0.1" plugs go into), so it would absolutely be possible to do a custom setup with leads ( ) on the RGB/sync pins to wherever you want them to go.

You could even have your controls, coin, power, etc. all plugged into the 0.1" headers on the board as normal, but have the video coming from the edge connector pins.

The problem you're going to have with this is that Nintendo boards output inverted video, so you're going to need an inverter somewhere in the circuit (or do it with software if you're capturing to a PC).

loves it, I reckon.

 

Yeah, since allegedly used a "direct video feed" (and definitely, absolutely not stitched-together MAME footage) to get his last 3 world records (including The Tape in KoK) you could just ask him how he did it! must know how this was done too, since he verified two of those submissions...

[f_symbols]

Yes it was a DK, and Richie actually had an additional, ORIGINAL radar scope monitor, that he had sitting on the top, and it was spliced into the video wiring harness, IIRC.

[jumpman]

You can definitely run 2 sanyos from 1 cabinet. You can just splice or re-pin the video signal connector from existing harness and run to extra monitor. You would need a connector on the end of the wires running to extra monitor. I never thought about using the un used edge connector you mentioned. My cabinet uses a edge connector so I can switch out different pcbs quickly. Let us know if that works.. But no matter what do not plug the extra Sanyo into a wall outlet. You must use the plug in inside the cabinet because it needs the isolation/step down transformer that supplies the Sanyo with 100v. 120v is bad news for a Sanyo.
Check out the old Bally midway factory made auxiliary monitor.

[YesAffinity]

Okay, I got one of those jrok rgb to component/composite boards.  I have the video and power connectors, and a speaker wire to rca connector, soldered to a 44-pin edge connector. 

I am testing voltages at the edge connector, and do not find the voltages that should be present per this pinout:

https://www.mikesarcade.com/cgi-bin/spies.cgi?action=url&type=pinout&page=Nintendo_Classic.html

My dc voltages, on the parts side (from the top) are:

0 (ground)
0 (ground)
24.1 (should be +5?)
0 (should be +5?)
3.9 (should be +12?)
-4.7 (should be -5?)

I soldered the +5v for jrok board to the pin that is producing 24.1v, but when I turn it on, the screen is blank.

Anybody know why these voltages are not what the should be, or possibly that on Mike's Arcade is wrong?

I checked all the grounds, too, and they all have continuity, and have continuity to an equipment ground connected to one of the coin door screws (presumably grounding the coin door).

:edit: Problem potentially solved.  That pinout I linked is oriented from the position of looking at the bottom of the edge connector.  The 24v I was reading above is for the counter.  I guess I should have verified voltage positions before completing all my soldering. 

[jammyyy]

soldered to a 44-pin edge connector why? why are you fkin with the edge connector? just split the video cable off the board in to a Y plug one end i to monitor and the other end in to your RGBS to rca video component converter , and do the same with the audio line off the board , its non amplified so you can plug directly in to your computer, or yes you can get a 44 pin edge connector and take feed off the edge connector,,video to your RGBS to rca video component converter to a capture devise for computer and plug the audio to sound card line-in input
The pinout mike has is correct ,,,, did the 24v fry your converter board





 

[YesAffinity]

The edge connector seemed a cleaner route to go.

Maybe I'm not versed enough in looking at pinouts, but the 24v on the parts side is toward the rear of the cabinet, with the +5v toward the front of the cabinet.  You have to hold the printout of the pinout in the air and look up at it, with the print upside down, in order for it to align with the pinout on the board. 

It might have fried it.  When I plug in the converter board, brightness on the monitor goes way up and I'm getting garbage from the output of the converter board.  When I unplug it, the monitor image is perfect again.  The power LED on the converter board lights, though.

I have an e-mail in to rjok, to hopefully solicit his feedback.  Looks like this project just got put on ice for an unknown duration of time.

Do you think the speaker+ output will work, if routed into a capture card?  I had the audio output wired from the unamplified audio originally, but it seemed to disable the cabinet speaker.

[YesAffinity]

I pinged jrok, and it seems the video encoder is doing what it should, considering the inverted video.  The inverted video, however, is more than just upside down as I thought it to be, and could be fixed with software (OBS has options to flip and rotate streaming/capturing video).  The issue involves voltage on the color signals, and jrok confirmed that the encoder board v4.1 will not work with a stock DK output.  He said the Nintendo-to-Jamma adapter from Mike's Arcade should work, and I notice that it corrects for inverted video output and has an amplified audio output.  I have one on order as of this morning.  God willing, I get the $50 bounty I submitted for in the DK Open, and this extra part will be paid for.  Once I get this solution working, there will be some simple schematics and a parts and price list, for anyone wishing to do the same in the future.

[YesAffinity]

I'm making progress on this project, but still not getting good video.  I got the inverter and audio amp board from mike's arcade.  I've wired everything correctly, as far as I can tell.  Attached is a line diagram and a picture of the video.  If I mess with the R, G and B dials on either the inverter board or the jrok v4.1 encoder board, it affects the gray lines, but never turns into anything close to resembling a good image.

Hopefully I'm missing something simple.  Anybody notice anything I'm doing wrong?

[YesAffinity]

Well, I am making progress, although I am not yet at the end game.  I got a jamma extender and put quick disconnects on the R,G,B,S,12V,5V and Ground lines.  I tested the inverter board and jrok board individually.  I am getting good video out of the inverter board, projecting on my JAMMA cabinet, while simultaneously getting good video on the DK cab.  Picture attached.

Pulling video from the JAMMA cabinet and a street fighter PCB, I am still getting no video signal out of the jrok board.  :-\

[YesAffinity]

Line diagram of the JAMMA/jrok test setup attached.  The only thing that I can think may be an issue with the test setup is pulling video signal from the SF PCB.  In my mind, this is logically where the signal is derived, but should the signal be wired from JAMMA monitor to jrok board?

[tilt]

Have you been able to verify that the jrok works with the CGA video signal from the street fighter board?  If anything, it should be able to encode that video.  After you do that and it still doesnt work, I would contact the jrok guy because if you have done all this testing and the screen still shows grey bars, something is wrong.

[YesAffinity]

Yes, I tested the jrok board with the video output from the street fighter pcb.  A picture of the line diagram of that setup is attached to the post above yours.  With that setup, taking composite and component (testing each individually) to a hdtv, the tv says 'no signal'.  I then removed the test setup, and re-connected the sf board in the jamma cabinet, and the game displayed normally (just triple checking that all the 'know good' components were still indeed good).

I've sent the info to jrok, hopefully he responds soon.  I am eager to get closure on this project and have a working custom video capture solution.