Build Your Own Arcade Controls Forum
Main => Monitor/Video Forum => Topic started by: Marsupial on June 23, 2010, 11:09:03 pm
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My search skills aren't good ennough to come up with a definitive answer, and I am too n00b to guess it.
I have an old goldstar EGA monitor from my first IBM-compatible computer years ago. It was working like a charm last time I tried it.
Is this thing compatible with medium-res arcades? They do call it EGA, should be the same?
If this has been covered somewhere before, please do point me in the good direction, because I can't find an appropriate answer... and if the monitor is good to go, I might decide into getting some PCBs soon. :D
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Yup, you should be able to hook 'er pretty much right up to a medium res arcade game, assuming it supports negative composite sync (probably does).
Unless it's a multisync, it won't work with (much more common) standard res (CGA) arcade games, though.
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As far as I know (or remember from ages ago) the EGA were backward compatible with CGA, no? I am almost certain I remember playing some games in CGA modes.
In any case, that's great news! I knew there was a reason I wasn't throwing this out years ago!
Now I need to take it out of storage from my parents basement, I feel lucky they didn't throw any of my things out. lol.
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some where and some weren't. i think it was more or less the computers job to "emulate" the cga.
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Wikipedia
http://en.wikipedia.org/wiki/Enhanced_Graphics_Adapter (http://en.wikipedia.org/wiki/Enhanced_Graphics_Adapter)
states EGA refresh rate to be compatible with 15.7 or 21.8 kHz hfreq @ 60 Hz vfreq.
How do we know what graphics mode a game uses? maws seems to state only the 60.000 hz.
I am interested in games such as arkanoid, would want to know if the PC EGA screen is a good way out for such PCBs.
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Never trust wikipedia for blanket statements like that.
There are lots of EGA monitors out there that would also support CGA timings (multisync). There are also plenty that won't. If you try it, you probably won't hurt anything, but it won't sync up, so give it a whirl.
Most arcade games, especially classics, are CGA ("standard res", 15-15.5kHz). Some, mostly ones designed for dedicated cabinets, are EGA ("medium res", 25kHz). Some newer ones (early-mid 2000s) are VGA (640x480 progressive, 30-31kHz). Some really new stuff is designed to run off HDTVs and sometimes actually runs them at 720p or even 1080p, but those are not games you're likely to encounter in home usage any time soon (they're mostly dedicated racers and gun games).
Vertical refresh rates vary. Most monitors can be adjusted to handle anything from about 47-63Hz. There is a tradeoff between vertical refresh (faster means less flicker) and vertical line count (higher resolution means a sharper picture). Many arcade games also timed everything to the vertical refresh, so slowing that down meant that less processing had to occur for each "iteration" of the game, which was sometimes necessary if the hardware couldn't quite keep up.
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Thanks a lot for the info MonMotha.
Not that I trust wikipedia, but I don't quite know where to get my info otherwise... most reading I've had on the web about EGA seems to say they *should* be backward compatible with CGA, and I am almost certain I could play in CGA mode with the monitor back in the day (altough it might have been some tweak of the graphics card)
Without having an actual arcade PCB to test it on, is there any specific way? Can those EGA monitors run off arcadeVGA?
And... how do we know what mode a game would, prior to purchasing some PCBs?
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Thanks a lot for the info MonMotha.
Not that I trust wikipedia, but I don't quite know where to get my info otherwise... most reading I've had on the web about EGA seems to say they *should* be backward compatible with CGA, and I am almost certain I could play in CGA mode with the monitor back in the day (altough it might have been some tweak of the graphics card)
Without having an actual arcade PCB to test it on, is there any specific way? Can those EGA monitors run off arcadeVGA?
And... how do we know what mode a game would, prior to purchasing some PCBs?
There is a lot of information in the monitor wiki.
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fact of life... true EGA is 21.8 Khz as defined by VESA standards and was aimed at the computer industry as an upgrade from CGA. The arcade industry developed "Mid-res" which is 24.3 kHZ (BTW all this is horizontal scan rate).
Some people in the arcade industry called this 24.3 Khz as EGA which not in fact true.
So there is a strong chance your EGA PC monitor will not work in a 'medium Res" arcade game.
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fact of life... true EGA is 21.8 Khz as defined by VESA standards and was aimed at the computer industry as an upgrade from CGA. The arcade industry developed "Mid-res" which is 24.3 kHZ (BTW all this is horizontal scan rate).
Some people in the arcade industry called this 24.3 Khz as EGA which not in fact true.
So there is a strong chance your EGA PC monitor will not work in a 'medium Res" arcade game.
Interesting, the last true "EGA" PC monitor I had died like 15 years ago. I've just had multisyncs since then, so they didn't care much about what I fed them (and of course almost no PC monitors now will go below 30kHz). Thanks for that tidbit.
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fact of life... true EGA is 21.8 Khz as defined by VESA standards and was aimed at the computer industry as an upgrade from CGA. The arcade industry developed "Mid-res" which is 24.3 kHZ (BTW all this is horizontal scan rate).
Some people in the arcade industry called this 24.3 Khz as EGA which not in fact true.
So there is a strong chance your EGA PC monitor will not work in a 'medium Res" arcade game.
Any chances I can tweak that off with the h-sync potentiometer?
Can true "mid res" arcade monitor resolution be achieved with soft-15khz? I am very curious to give that a try, for knowledge sake.
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Any chances I can tweak that off with the h-sync potentiometer?
There's certainly a chance, if it has one at all. It may or may not have that kind of range (and it may be unhappy running up at that higher frequency, possibly even suffering damage).
Can true "mid res" arcade monitor resolution be achieved with soft-15khz? I am very curious to give that a try, for knowledge sake.
Yup. Hit the "Install 25k" button.
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I suggest not bothering with trying to 'force' the use of this monitor.
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I suggest not bothering with trying to 'force' the use of this monitor.
Why so?
I have it on-hand, will try and have it run somehow. Its not like it cost me anything if I break it, its been sitting on a shelf for about 15 years doing nothing.
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Mmmmm.....have a go I guess. Report back.
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I will try it for sure. This monitor is pointless if I can't use it. Huge paperweight. lol.
Plus, there seems to not be many people who tried that. I don't know how many PC EGA monitors are still out there, can't be that many as everyone was going VGA in those years.
But I am still stuck unboxing, being that we moved recently. I still haven't found my tools in all this mess. :laugh2:
When I have time to spent on fun stuff, I'll give it a try - I mainly need an EGA-VGA conversion cable and soft15khz as an initial test.
Worst case scenario: the EGA monitor stop working. :dizzy:
Best case scenario: I get to put an EGA monitor in a minicab. :burgerking: