An ESP32 Monitor for Your Desktop Computer

Just in time for Christmas, mechanical engineer Tucker Shannon has created a tiny, elf-sized monitor for a desktop computer. At 1.14 inches and with a resolution of just 135x240 pixels, it isn’t useful for most digital tasks. But for remote monitoring dashboards or IoT displays, it could come in really handy. Aside from that, you won’t find a cuter display anywhere.

As far as the hardware is concerned, all that is needed is a TENSTAR T-Display ESP32-D0WD. This all-in-one board comes equipped with an ESP32 microcontroller — which provides both processing and Wi-Fi capabilities — as well as a miniature display.

The software consists of two primary components: a transmitter that runs on the host computer, and a receiver that runs on the ESP32 board. The transmitter takes screen captures from the host machine, then finds pixels that have changed since the last capture. These pixels are then run-length encoded and sent to the receiver via a custom protocol over Wi-Fi to update the display.

Given this method, frame rates vary wildly from about 5 to 60 frames per second. The number of changed pixels between frames heavily influences this, but the quality of the Wi-Fi network also factors in. With 100 milliseconds or so of delay on average, you won’t be doing any tiny gaming, but it won’t matter much for most dashboard applications.

The source code and setup instructions are available on GitHub. If you have this little board already, it would be a fun project to play with over the weekend.