Tiny e‑Paper Board Achieves 30 FPS Game Boy Emulation

Bo built a Game Boy emulator that can run at 30 frames per second on a 1.54‑inch Waveshare ESP32‑S3 e‑paper display. The board uses a built‑in e‑paper controller, which normally drives a slow‑refresh screen. By addressing pixels individually, Bo managed to keep the frame rate high despite the display’s limitations.

Unlike Wenting Zhang’s earlier project that used bare inputs, Bo’s setup goes through the controller’s blob. The board still allows pixel‑level control, but the controller adds a layer of processing. Bo credits Zhang for inspiring the idea and for his PaperBoy project, which showed that e‑ink could handle Game Boy graphics.

To create the Game Boy’s 4‑bit greyscale, Bo used deliberate ghosting. Pixels are not driven long enough to fully flip when only one shade changes. This means that turning a black pixel to white takes more pulses than moving from white to the next darker grey. The timing for each transition had to be carefully calibrated.

The calibration required a lot of trial and error. Bo used video to automate the process, adjusting the pulse count for each color change. The calibration is still ongoing, and no GitHub release exists yet. When completed, Bo plans to open‑source the code and use the display in a PDA‑like device.

The project shows that, with clever pulse‑budgeting and ghosting, an e‑paper display can deliver 30 FPS for retro gaming. It builds on the same underlying technology used in a recent 20 FPS e‑paper hack, demonstrating the potential for low‑power, high‑frame‑rate applications on e‑ink.