The Cheap Yellow Display has become the default answer to “I need a screen on a microcontroller.” It’s an all-in-one ESP32 board with a touchscreen, it costs very little, and it turns up in a large share of hobbyist projects that need a display without a design effort.
Nickm324’s ESP32-CYD-MiniTV, picked up by Hackaday on September 17, uses one as a miniature television — in a 3D-printed retro cabinet, with channels.
How it works
Media lives on an SD card, organised into channels, each holding different files. The board plays synchronised .mjpeg video with a separate audio file. Navigation is deliberately minimal: the board’s BOOT button, one button, the way an old TV had one dial.
The MJPEG choice is a constraint doing useful work. The older ESP32 in the CYD can’t decode modern video codecs — those depend on motion compensation between frames and hardware acceleration. MJPEG is just a sequence of JPEG stills, each decoded independently, which an ESP32 can manage one frame at a time. Keeping the audio in a separate file and synchronising the two is the standard workaround for having no container format or A/V muxing to lean on.
The result is inherently low-fidelity and inefficient — no interframe compression means every frame is a full image — but it works, on a board most people already own.
Why this is more interesting than it sounds
Three reasons this is worth a look beyond the novelty.
It’s a finished object, not a demo. Firmware, a physical enclosure, and an interaction model that a person who has never seen it can operate. Hobbyist projects usually stop at “it renders on the bench.” The 3D-printed cabinet and the single button are what make it a thing rather than a test.
One button is a real interface decision. A CYD has a touchscreen and this project mostly ignores it. Choosing a button over the touchscreen makes the object behave like the thing it’s imitating, and it’s a sharper choice than adding a menu because a menu was available.
It’s a good display target for artists. A small screen with channels of looping video, on a cheap board, in a case, is a distribution format. Video artists have been putting work on small screens in galleries for decades using far more expensive and fragile kit. This costs roughly the price of lunch and runs from a card.
The project builds on an earlier ESP32 mini TV player, which is how most of the good hobbyist work happens — someone takes a working thing and makes it more finished.