To drive the LEDs, [Ole] is using an Arduino. Even though the WS2812s are individually addressable and only one data pin is needed, [Ole] is using five individual data lines for this matrix.

WS2812 neopixels are addressable RGB LEDs. The integrated controller chip allows you to change the color of the LED and address each individual LED. The WS2812 comes in two versions (WS2812 & WS2812B) ...

It can display scrolling text at 80 frames per second. You can make your sign as long or short as you like. The majority of the cost for a big sign comes from the LED strips.

The Arduino can just increment the counter up to the appropriate LED. The Arduino then controls the state of the LED using the active high enable line from the column multiplexer chip.

LED Automotive Display System A dynamic LED matrix display system for automotive applications featuring sequential turn indicators, scrolling speed display, and cruise control status indicator. 🚗 ...

Controlling WS2812 Tricolor LEDs (aka NeoPixels), Part 2 Turning a LED on is easy. Preventing it from blowing itself up is a little harder.