JAMMA to Monitor?

Started by Tupin, January 09, 2010, 06:47:08 PM

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Tupin

Hi, I'm new to the whole arcade scene, and I'm trying to assemble a SuperGun using the parts I currently have, and the monitor I want to use is a Tandy CM-4 RGB monitor. It does operate at 15Hz horizontally, but I don't know about the other requirements. Here's the pinout (male cable, wire coming out of monitor):

1 Ground
2 Ground
3 R (Red Video)
4 G (Green Video)
5 B (Blue Video)
6 Intensity
7 No connect
8 Horizontal Sync
9 Vertical Sync

phreak97

Welcome to GameSX:)

Alright,
first up, google for a jamma pinout, you'll find most of those connections are labled exactly the same on the jamma harness, you should be fine just conneting them straight in with just wires at least to begin with. You  can ignore the intensity pin, I'm not really sure what it does, but I've never seen anything output an intensity line so I'm going to guess they made it an option, otherwise the monitor wouldnt be too useful.
what you'll notice is that jamma outputs composite sync (may just be labled "sync"), and your monitor wants horizontal and vertical seperately. try connecting the composite sync line just to the horizontal sync pin on the monitor, if it works, awesome, if it doesnt, I'll help you some more:)

arcade rgb levels are higher than typical rgb, so the picture might look a bit too bright, we'll work on fixing that later too, just see if you can get something to come up:)

this is assuming you've at least got a working jamma pcb and a harness with at least the power lines connected.

Midori

I'm to lazy to google right now but it sure sounds from that pinout as that your monitor is a digital RGB one. Separate Syncs(only separate, no composite) and intensity pins are more or less only found on digital monitors, especially the intensity function.

So that monitor will most likely be no good for arcade boards which mostly output analog RGB.

phreak97

#3
lots of analogue monitors have seperate sync inputs, but the intensity pin had made me think it might be digital. I figured he could try it and see what happens.

a quick google search shows the cm-4 is most likely a cga monitor, which wont be of any use.

the best small monitors I've found are the commodore 1084 and 1084S, if you can find one of those you'll be set, they pretty much work straight away with any 15khz rgb input.

Tupin

I've changed my plan anyway, I'm going to use an AppleColor RGB Monitor, an analog RGB monitor.