Macintosh System 1 on a Sharp Memory Display

The Playdate has come to be a favorite among casual gamers. Much like the Game Boy, you can pick it up, start a game almost instantly, and play for a few minutes here and there when you’ve got some downtime. It has a great library of games, and the crank really adds something unique to the experience. But far and away the most special feature of the Playdate is its display.

It comes equipped with a Sharp Memory Display, which is something like a cross between an E Ink display and an LCD. The graphics are super-sharp, and it has the low energy consumption of E Ink with the fast refresh rates of an LCD. Vaclav Krejci loves the display so much that he bought a 2.7-inch, 400x240 resolution Sharp Memory Display module much like the one in the console.

Of course the display by itself isn’t of much use, so Krejci also dug in to understand how it works and then interfaced it with a Seeed Studio XIAO ESP32S3 development board. While many hobbyists default to the popular Arduino Uno for these types of projects, its limited RAM is insufficient for a screen of this resolution. To store the data for 96,000 pixels, a larger buffer is required, which the ESP32-S3 can easily handle.

To bring the hardware to life, Krejci used Adafruit’s GFX and Sharp Memory Display libraries within the Arduino IDE. However, the project wasn't without some difficulties. Initial tests revealed that the display logic was inverted, rendering what should have been black as white. This was corrected during the image conversion process, where PNG files were inverted before being transformed into C-style arrays using an online "image to CPP" tool.

After seeing some images on the display, Krejci realized that the display perfectly recreates the high-contrast graphics of Classic Mac OS. By capturing snapshots from a browser-based emulator and resizing them to match the display’s resolution, he recreated the 1984 Macintosh interface in miniature. The finished project functions as a nostalgic digital frame, cycling through iconic windows and icons that look more crisp today than they did forty years ago.

What would you use a Sharp Memory Display for? Be sure to let us know if you make something interesting!