Medium resolution CRT

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Slm4x4
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Medium resolution CRT

Post by Slm4x4 » Mon Jun 01, 2020 3:50 pm

Wanting to verify that ARpiCADE can run on medium resolution. I have a well Gardner 7500 27 inch in an old golden tee cab I plan to use for this build. What Different HZ can ARpiCADE Run at?

dee2eR
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Re: Medium resolution CRT

Post by dee2eR » Wed Jun 03, 2020 11:52 pm

The pre-done setups are for low res (15k) and hi res (31k).

Unfortunately I do not have any medium res gear to test 24k. (in theory the hardware can do it....)

Elvis151
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Re: Medium resolution CRT

Post by Elvis151 » Thu Jul 22, 2021 3:06 pm

I also have a WG 7500 27" medium resolution monitor from a Power Putt cabinet. If you wanted to test 24K with the Arpicade, I have assembled everything necessary.
I have purchased (2) of the arpicade and I have (2) standard resolution arcades up and running, 1 horizontal and 1 vertical.
I have (2) 27" monitors on my kitchen table. One is the WG 7500 medium resolution and the other is a Neotec trisync monitor. The Neotec displays the signal frequency. I have also purchased a TPG with standard and medium resolution to test both monitors to show they are both functioning properly.
The thought is that I could connect the arpicade to the Neotec monitor to verify the 24K signal before connecting it to the WG 7500 medium resolution monitor.
I purchased my arpicade with image back in April of 2020, so I may not have the most recent version.
I just happen to live near Highscoresaves, so he was over and looked at my setup. He stated that only 1 in a 1000 would want to run medium resolution, but that the forum would be the best way to proceed. If you are interested in tesing a 24K setup, I like to be the one to do it.

dee2eR
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Re: Medium resolution CRT

Post by dee2eR » Fri Jul 23, 2021 2:20 am

That's very generous of you @Elvis151, thanks.

I'll setup a test and get back to you. I'm assuming you're on a Pi3(?)

Elvis151
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Re: Medium resolution CRT

Post by Elvis151 » Fri Jul 23, 2021 12:43 pm

Yes, I am running a Pi 3 B+

dee2eR
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Re: Medium resolution CRT

Post by dee2eR » Mon Jul 26, 2021 8:57 am

So after a little research, short of a custom resolution that I wouldn't be able to test, the Pi can output 3 resolutions that look like they're 'medium res'. Unfortunately they're all 85Hz, I'm not sure what leyway a medium res monitor has for refresh rate but 85 sounds high...

These values are valid if hdmi_group=2 (DMT):
hdmi_mode Resolution Frequency Screen Aspect Notes
1 640x350 85Hz
2 640x400 85Hz 16:10
3 720x400 85Hz

Based on the logic in the res switching script it should be OK to try changing to one of these in config.txt, at least from the perspective of the system shouldn't surprise change to another res. I'm not sure I recommend trying these though, to be clear, do not feel pressured to try 85Hz. If you do want to give it a go, of the three 1 is likely to be safest as it draws the least lines - the lower vertical resolution may compensate somewhat for the higher refresh.

For 60 Hz we would have to try a custom mode and modify the res switch script to suit. I should be able to figure out a 640x384@60 mode, at least mathamatically, I don't think I can test it to confirm it's right (unless one of my LCDs will accept medium res inputs). Does that sound like a suitible set of numbers for medium res? I've based it on : https://www.arcade-museum.com/monitor.html and the fact I've made 640 width resolutions previously (which simplifys the maths to figure out a res, I wouldn't be starting completely from scratch). If 512 width (as reported on KLOV) is vital I can probably figure that out too.

If not 640x384@60 is there a medium res that is recomended? MAME reports 512x384@60.096153 for Super Sprint (first medium res game I thought of) - I could aim for that exactly, not sure if other medium res games used other widths, lines and refresh rates.

Elvis151
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Re: Medium resolution CRT

Post by Elvis151 » Tue Aug 17, 2021 7:04 pm

I do not know much on the monitors, so I did some research. My medium resolution is a WG K7500 and I tested it with a 24K test pattern generator and it looks great. According to the WG manual, the monitor input accepts a 25K horizontal sync frequency and a 640 x 400 resolution. It does not look like the Pi has a refresh rate close to a medium resolution monitor. I appreciate you looking into it, but it does not appear that this would be a good investment in your time since there would be so few people who would benefit from it. I was hoping it would be a simple solution.

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