VGA16 FPGA based Scan-Doubler for the Neo Geo

Beharius

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VGA16 Scan-Doubler for the NEO GEO
We are releasing an FPGA based line-doubler for the Neo Geo MVS arcade boards which is installed internally. It's outputting a progressive VGA signal (640X480) by tapping the digital video signals from the board. There is no loss in video quality and no lags since a frame buffer is not used. Its FPGA line doubles the signal on the fly (264 lines to 528) then handled by a DAC similar to the original Neo Geo design which converts it to analog video. Hence it's refresh rate frequency is off spec(59.1856Hz) instead of the required 59.94Hz for the 640x480 video timing format, more tolerant VGA output was preferred instead of the strict HDMI standard for compatibility issues.
The installation is very simple unlike the other internal digital video mods out there. There are only 20 wires to be soldered. It uses 5 bits per each RGB colors(5x3), a sync signal, a CLK signal taken from the 68000 CPU(or mainboard), 2 grounds and a 5V. So 20 wires in total. These are all next to the 74ls273 latches, on the resistors.
This mod also offers Scanlines and Pixel Blending features. These can be set by the jumpers on the board or a dip-switch to be installed on the enclosure. You can set its density by setting jumpers as 00 none,01 low,10 medium, 11 high. Pixel blending give a nice CRT experience for the user.

https://flic.kr/p/2fuifwE

MV-1F installation
https://flic.kr/p/2fyXuTK

MV-1C installation
https://flic.kr/p/2fuifAs

https://www.youtube.com/watch?v=2mA1QCSoqO4

This project will be offered as a DIY kit including all the wires, please note that final boards will have an 20pin IDC socket, so only wires for the MVS mainboard need to be soldered. We will also release a limited edition, premium Consolized MVS to commemorate our 7th anniversary. This will feature a car painted high quality metal enclosure including VGA(480p) and Scart(480i) outputs. An original, upgradable UniBios. Each bios can be individualized for your needs(name, serial etc.) too.


Price will be $100 including shipping. Pre-ordering TBA soon.
It's developed by our new FPGA coder, Eins, a very experienced designer in this field. So more to come soon...


BEHARBROS
www.beharbros.com
 
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ChuChu Flamingo

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Beharius

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May 17, 2011
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Garo was designed according to the reference design in the manufacturer's datasheet.
We're currently testing a possible fix for those incompatibility problems. It should be understood that pro monitors are not tolerant as consumer ones. Garo works even with the cheapest monitors or hdmi converters on the market without any lssues. Majority of converters we have tested so far have similar or worse issues and Garo is performing better than the rest.



Will you guys ever fix the Garo? I reckon working out the kinks below would be more beneficial to the retro community than VGA on neo geo. Especially since you can accomplish this with any line doubler. In any case there is a severe lack of good options for component to rgb.
.
https://www.reddit.com/r/crtgaming/comments/awxqyk/warning_about_new_behar_bros_garo_transcorder/

https://shmups.system11.org/viewtopic.php?f=6&t=55158&start=210
 
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