LED Matrix (early 2021)

In early 2021, I was looking for a project to do. Given that I wanted to gain experience making microcontroller PCBs, and I had all the know-how of multiplexing from the LED cube project, I decided to make an LED matrix. It's an array of 32x12 0805 LEDs controlled by an ATMega328 and 6 shift registers. Each row of 32 LEDs have their cathodes connected together, and each column of 12 LEDs has their anodes connected together. Conveniently, this allows for 4 shift registers to control the LED output as a 32-bit word, and two shift registers to control the row-select.

For fun, I added buttons to manually control the SCK, RCK, and SER pins of the shift registers. Additionally, I added a potentiometer that the microcontroller reads to adjust the brightness of the LEDs via PWM. The github for the project can be found here. See below for a demo of the final product. I wrote a program in Java (did not, at the time, know Python) to take an image and generate corresponding C arrays to display the image on the matrix.