Computer scientist Dave Luna has put together a Commodore PET 64 with a difference: it serves as a stealth-build docking station for considerably newer machines, complete with color screen and working keyboard.
"The Commodore PET 64 was my very first computer, and I have so many fond memories of sitting awash in green screen light while trying my best to write BASIC programs that never worked right," Luna recalls. "The PET died sometime in the late 90s, but I held onto it. I removed the CRT and motherboard back in 2005 when I decided to retrofit it with a PC, but I never got around to finishing that project... until now."
The PET 64 was an unusual education-focused system from Commodore, first released in 1982. While externally the machine resembled the earlier PET (Personal Electronic Transactor) microcomputers, complete with green-screen single-color monitor in the first models, the PET 64 housed the hardware of a Commodore 64 with modified ROM identifying the machine as a "Commodore 4064."
With the original hardware long since gone, Luna's stealth-build was a complete ground-up replacement. "I inserted a generic 12" TFT LED Point-Of-Sale monitor that doesn't have great picture quality, but it's a perfect fit," Luna explains. "I connected that monitor to a WAVLINK USB 3.0 DisplayLink adapter and attached that adapter to a powered 7-port USB 3.0 hub. I used an Arduino Micro and [the] Cheap and Easy Arduino C64 Keyboard to USB Adapter tutorial from Retro Game Coders to adapt the Commodore keyboard to a USB interface."
The hardware is housed entirely within the original chassis, leaving the exterior largely unchanged — bar the new color display and a pair of USB ports, which sit where the nine-pin joystick ports would originally have been found. By connecting the machine to a host via USB, it's possible to use both the keyboard and the display — streaming the video via DisplayLink over USB to the new monitor. A USB replica of the Amiga-style "tank" mouse completes the build.
"The Commodore keyboard is great for nostalgia's sake," Luna notes, "but it's not a very satisfying typing experience. So, my next update will be building a DIY MechBoard64 mechanical keyboard to add a little clicky-ness to the PET."
The full build walkthrough is available on Luna's website.