Build the Ultimate POV Display Using 144 LEDs and a Digilent Cmod S6 FPGA

POV (Persistence of Vision) LED displays are fascinating in how they project images and video through an optical illusion, which compose images by displaying one spatial portion at a time in rapid succession. One of the better POV displays I’ve seen comes from Patrick Knobel, with his “One POV Display to Rule Them All project.”

According to Knobel, “I iterated on my design to make it as easy as possible to rebuild. There are no SMT components, and everything should be solderable by beginners. Don't get me wrong, it's still a very big challenge to put everything together, but it should be doable!” Knobel began his build looking for an MCU to drive the video stream, and chose the ESP8266 as he could send the signal via Wi-Fi, but ended up scrapping it, as it didn’t offer enough power or bandwidth (16FPS). Instead, he chose the ESP32, and while the bandwidth remained the same, it had more than enough computing power to decode video streams, so he used the MCU to host a website that can stream JPEG files.

To drive the LEDs (Adafruit DotStar Digital LED strip), Knobel chose to use that ESP8266 to power a DC motor, and Digilent's Cmod S6 FPGA paired with a Hall Effect sensor to keep tabs on the LEDs as they spin. The POV works by having the ESP32 push the image frames to the FPGA, which processes the signal while matching the frame rate of the ESP8266-powered DC motor. Knobel housed his build inside of an MDF enclosure, keeping everything neatly packed away from the spinning LEDs. For those who would like to recreate Knobel's POV build, he has provided a detailed walkthrough on his project page.