If you grew up with these older Game Boy devices, you probably remember two things: the games you loved, and the squinting you had to do to actually see them. Those early handhelds were marvels of portable gaming, but their reflective LCDs relied entirely on ambient light.
Today’s modding scene has solved that problem with modern IPS and even OLED screen replacement kits. These upgrades bring bright, sharp, full-color backlit displays to systems that were never designed for them. But have you ever wondered how it’s possible to retrofit modern screens into old hardware?
Let’s use the original DMG-01 Game Boy as an example. Its 160×144 pixel reflective LCD worked by twisting liquid crystals to allow or block light between two polarizers. Vertical and horizontal electrodes controlled which pixels appeared dark. Instead of connecting directly to the CPU (which would require hundreds of pins), two “driver” chips bonded to the glass handled the job: one for the columns, one for the rows. The CPU sent pixel data serially, timed by a pixel clock, while the drivers took care of applying the right voltages to the right electrodes. This approach wasn’t unique to Nintendo; pretty much every device with an LCD screen used a similar design.
Fast forward to today. Modern replacement kits don’t rip apart the console’s logic; instead, they intercept the original LCD driver signals and translate them into something a contemporary screen understands. The translation is usually handled by a small chip on a driver board – often a CPLD (Complex Programmable Logic Device).
In the case of the popular FunnyPlaying M2 GBA kit, the board is powered by a Pango Micro CPLD. It takes the Game Boy Advance’s native screen data signals, reinterprets them, and sends them to a high-quality IPS panel originally designed for a Canon EOS M-series camera. Yes, your GBA can literally be running on a camera screen.
A CPLD isn’t strictly required, and neither is the Canon display. With a $4 Raspberry Pi Pico, you can tap into the original system’s pixel clock, data lines, and sync signals, and drive an SPI display. It’s not as polished as a commercial kit, but it’s a great way to understand what’s going on under the hood.
If you want to learn this process hands-on, I’ll be hosting a Gameboy Advance Refresh workshop at RetroWorld Expo 2025 in Hartford, CT on Friday, September 12th, alongside Tito from Macho Nacho Productions. We’ll guide you through replacing your GBA’s screen with a backlit IPS panel from start to finish. Space is limited, so grab a ticket if you’re interested.
And if you enjoyed this high-level look, then I would encourage to check out the full video. In there, I get into the nitty gritty with animations, custom-made 3D models that I use to illustrate concepts, and a couple of neat experiments that most people didn’t know were possible. I think you’ll enjoy it!