MDT9100

In order to replace the i386 with a BeagleBone Black it was necessary to build an adapter board that plugs into the ribbon cable, deduce the VGA timings and write a Device Tree overlay (DTBO) to configure the LVDS framing for the special screen, and design a USB HID keyboard interface for the keyboard and function keys. Using a 5-bit R2R resistor ladder (similar to my first Vector display), the top bits of the green channel of the LCD output ( – ) can be merged into an analog value for feeding into the CRT. The qwerty section is on the left half of the ribbon cable, the function keys are on the CRT section. Six of the rows are shared with the function key section and @phooky mapped the additional five pins going to the CRT section (columns 10-12, the large emergency lamp, a smaller RED LED).

Source: trmm.net