Comment by platevoltage

I'm working on restoring (or really resto-modding) a 1980's Japanese arcade machine.

https://share.icloud.com/photos/00ajYWxKpZmYrh6KmlHOxW4tA

I was able to get the original 15khz CRT monitor up and running by recapping the board. I decided that the control panel was unsalvageable, and insufficient for what I wanted to do, which was make this cabinet compatible with most any game that would have run on a cab like this.

I decided to use RGB lit buttons, so I could change the color's depended on which game was loaded. I used an ESP-32s2 to emulate a keyboard, and accept serial messages from the host computer that changes the button colors.

I also incorporated a Stream Deck in the control panel for auxiliary functions. I was able to write a node application to run the stream deck (with the help of a library) since there is no OEM software for linux.

By far the most challenging part was getting a suitable signal to the CRT. The first thing I tried was using the Raspberry Pi's GPIO pins through a VGA666 board, but this limited my colors to 16bit, which makes 3d games look pretty awful.

Next I tried using a downscaler. This got me 24 bit color, but resolution switching doesn't work with this method.

I'm trying an AMD system now. Apparently the linux driver lets you set custom resolutions, and output 15khz (and 25khz for that matter) right from the VGA port.

I plan on doing a writeup after I near completion.