G7000digitizer - c0pperdragon/LumaCode GitHub Wiki

This board can be installed into a vintage Philips Videopac G7000 game console to create a lumacode representation of the display. This lumacode signal can be processed with a compatible upscaler to deliver a pixel-perfext HDMI display.

Theory of operation

The circuitry is quite simple as all video information is available in digital form, so all that is needed is to serialize the 4-bit color information to lumacode which can be done with a flip-flop and a multiplexer. The sync signal can be taken directly from the main board and also mixed into the outgoing lumacode signal.

Inside the machine

This is the backside of the main board where the mod board is installed to. As this machine natively only provides a single RF output, an A/V mod is a good option in any case even when no G7000digitizer is installed. There are quite some resources available online how to do this, as this is beyond the scope of this documentation.

Installation details

To keep the installation simple, it is easiest to leave the main board in place. You then need to determine where the main video IC is located, so you can solder the mod board to its underside. I don't know how consistent the board layout is between different revisions. In any case it must be a 28-pin IC and probably located near the RF modulator. The mod board denotes pin 1 and the other pins are numbered in clockwise order (because it is mounted to the underside). To check if you have the correct IC and orientation, see that pin 14 is GND, pin 28 is +5V and pin 1 is CLK (which will show on a multimeter as a voltage somewhere in between). Solder the contacts of the mod board marked with white boxes to the main board.

In addition, two signals (VIDEO and CSYNC) need to be taken from the PAL encoder IC which could also be nearby, but is known to be quite a distance away on some board variants. See the picture about how to connect the wires. To make sure you find the correct IC and its orientation even with a different mainboard layout, you can check signal continuity from the video chip to this 16-pin IC on the following pins: 18,19,20 to 10,13,12 . Again remember that the pin numbering is clockwise because you look at the underside. Solder wires from the VIDEO1 pad to pin 11 of the PAL encoder, and from CSYNC1 to pin 8.

The lumacode signal and its GND can be taken from the LUM and GND pads and brought out of the case using some RCA connector (I propose a black one).

Alternative board layout (but also PAL):

Install in a Magnavox Odyssey 2

The installation is very similar to the PAL version. The main difference is how to get the CSYNC signal. Instead of adding a wire to CSYNC1, you need to just close the solder jumper JP1, because a working csync signal is already generated by the main graphics IC.

RGBtoHDMI software

The RGBtoHDMI software does not yet provide a profile and palette data for this machine. After installing the normal release, you can add the files from this ZIP to the SDcard to have a working profile: G7000_extrafiles.zip