CandyCab/GroovyMAME/CrtEmuDriver Build Help (Graphical Flicker)

[malkneil]

Hello Retro Gaming Folks,

I recently acquired a JP Capcom Impress candy cabinet with the hopes of fulfilling my dreams of turning one into a MAME cab. It came with a Pandora's Box multi board, which is pretty cool, but at the same time kind of janky and only has a subset of games on it.

After mulling over different routes to go down (FPGA/MAME), I decided to go with GroovyMAME/CRTEmuDriver. I bought a refurb Windows 10 box and got a Radeon HD5450 video card for it -- I believe the Impress cabinet has a Toshiba monitor in it (what they came with) but I'm not 100% on that.

I followed the Calamity tutorial online to get the new CRTEmuDriver installed and use VMMaker to generate the video modes, etc. All has gone pretty well so far -- I have my PC connected to the cabinet's JAMMA connector via a JPAC. When I actually launch games in GroovyMAME they look good (the few I've tested so far). My hangup seems to be when I'm outside of a game either just on the Windows desktop or in my MAME frontend (using FEEL at the moment). The picture has a good deal of flicker to it. I've run the Arcade_OSD tool that comes with CRTEmuDriver and I think Windows is displaying under the 640x480 interlaced mode. I've read on some forums that interlaced mode may be the problem.

As you've probably guessed I'm not a graphics/display/CRT guru, and some of the threads I've read up on pretty quickly get into the nuances of adjusting the graphics modes. Is there a list maybe of things to try from easiest to hardest in order to get a clean picture? Seems like if I can get the games to display OK, getting a frontend to do so would also be doable -- but this may be a lack of understanding on my part.

I guess in summary I'm not sure if my setup is good and it's just a matter of adjusting the video modes through Arcade_OSD, or if there are other literal or figurative 'knobs' I can turn such as a different OS, different video card, different frontend, etc. Is it possible the monitor I'm using the issue and therefore an insurmountable problem?

Thanks in advance for humoring this CRT rube,

Neil

[abispac]

i believe, that  for your monitor, anything that runs 640x480 will have that flicker. It depends from monitor to monitor, on my experience, a k7000 would look so good on anything, a 19inch with a weiyah chassiss would flicker at 640x480, same with my sony rgb moded tv. but on my samsung 13 inch moded tv, everything looks so great, no flicker at all. so i guess it depends on the monitor. perhaps you should try the 320x240 layout on feel to see if the flickers goes away on the frontend.

[malkneil]

Thanks abispac,

Yeah I did pull down some 320x240 layouts for FEEL but it seemed like it wouldn't switch to the resolution.  Would I be able to install one or more 320x240 resolutions via VMMaker (or some other way) so that my GFX card allows the monitor to switch to that resolution in FEEL?  Right now if I run Arcade_OSD the lowest resolutions shown are 640x480.

[buttersoft]

Right now if I run Arcade_OSD the lowest resolutions shown are 640x480.

But you have super resolutions listed, right? Like 2560x240?

to add a modes or modes, launch VMM and into the prompt type (hitting enter at the end of each line):
> modelist import
> modelist export modelist.txt
> mode add 320x240@60.00000 (((I might have the format wrong, there. Type help for help)))
> modelist list (((now look at the modelist. The 320x240p mode should be in there, and if it is...)))
> modelist install

The second line above is a backup - it grabs all your installed modes and their timings, and saves them. You can call the file anything you want, as long as you don't overwrite anything critical. To use that backup you would type:
> modelist import modelist.txt
> modelist list (((to see if the lines match the file)))
> modelist install

As to the other point: interlaced modes flicker. There's not much to be done. Using a flicker filter helps a little, but reduces sharpness. The only thing i've found that might ameliorate things is to use smushy sync (with thanks to Zebidee for christening it such). You blend sync for yourself by having the PC output separate sync and then combining it using resistors in each line. Add a ~500R resistor to each line along with a 1k pot, then combine and feed into the sync line of your monitor. If it helps, keep adding more fixed resistors, with a pot to dial things in. Don't go under 500R. This makes an absolutely monumental difference on my PVM-2730's, but doesn't so much for most other sets, so YMMV

[malkneil]

Thanks butter,

I'm slowly starting to understand some of this.  Just to respond to your post, I followed the Calamity instructions from online and he had you point to the "user modes - super" INI file when generating the modes.  I'm assuming all the modes generated have to be contained in that INI file you point to.  That said my "super INI" file only contains these modes:

## Desktop ##

 640 x 480 @ 60.000000 desktop

## Super resolutions ##

2560 x 240 @ 60.000000 super
2560 x 248 @ 60.000000 super
2560 x 256 @ 60.000000 super
2560 x 264 @ 60.000000 super
2560 x 272 @ 60.000000 super
2560 x 280 @ 60.000000 super
2560 x 288 @ 60.000000 super
2560 x 296 @ 60.000000 super
2560 x 304 @ 60.000000 super
2560 x 320 @ 60.000000 super
2560 x 336 @ 60.000000 super
2560 x 344 @ 60.000000 super
2560 x 352 @ 60.000000 super
2560 x 360 @ 60.000000 super
2560 x 368 @ 60.000000 super
2560 x 376 @ 60.000000 super
2560 x 384 @ 60.000000 super
2560 x 392 @ 60.000000 super
2560 x 400 @ 60.000000 super
2560 x 416 @ 60.000000 super
2560 x 432 @ 60.000000 super
2560 x 448 @ 60.000000 super
2560 x 464 @ 60.000000 super
2560 x 480 @ 60.000000 super
2560 x 496 @ 60.000000 super
2560 x 512 @ 59.000000 super
2560 x 544 @ 55.000000 super
2560 x 560 @ 54.000000 super
2560 x 768 @ 60.000000 super
2560 x 800 @ 60.000000 super

Would it be as simple as just modifying that INI to add a couple 320x240p resolutions to the file and then regenerate/install the modes?  Was looking at a few other posts on this site and saw a few reso's that maybe would fit the bill:

320 x 240 @ 59.014000 p64
321 x 240 @ 59.014000 am2r
640 x 240 @ 59.014000 am2r

To answer your other question, yeah all the other super resos show up in Arcade_OSD, so once again I think it's just a matter of generating the 320x240 reso(s).

Thanks much for your guidance.

malkneil

[buttersoft]

Yes, you can add more resolution to the ini file and generate all your resolutions again in VMM, that works fine. Down the line, when you have tweaked the modelines to suit your monitor and the games you want to play (width, height, etc) it becomes faster to add resolutions using the method i described, as you do not have to configure all the other modelines again, only the new one

I would also recommend taking a backup of your modelines every so often, makes reinstalling easier.

[malkneil]

Thanks again, I finally got it working in the 320x240 without any flicker.  This is huge.  Just got a kick harness adapter and cannibalized it to go from the Impress kick harness and wire into the JPAC screw-down connectors as well.  All six buttons working like a charm.  I know this is sort of off topic, but I think my last big hurdle is dealing with the sound.  My hope is to push the sound from my MAME PC through the Impress speakers.  I tried using a splitter that takes the 3.5mm audio out and splits it into RCAs and then connecting that into the Impress stereo (Qsound) connectors.  Doesn't seem to work.  I've read that if you're looking for mono only you can just cut up a audio out cable and connect the wires to the +/- on the JPAC...will this work?  Alternatively if I'm looking to also be able to get stereo for say CPS2 games  what's the easiest way to do that?  I was looking at the JammASD board (an alternative to the JPAC) and it does have an audio-in built into it (with a volume control pot), but I gotta imagine that would only provide mono since the JAMMA edge connector is mono-only?

Any pointers?

Thanks!

[buttersoft]

Nope, not for audio, sorry

I'm not using a j-pac so i don't know too much about them, especially not their audio capabilities. And i de-jamma'd my cabs (which were already partly de-jamma'd already, TBH) to use as MAME cabs.