A Maker by the name of Martin Atkins recently built an LED matrix clock using an Atmel-based Arduino Micro (ATmega32u4), a few bicolor LED matrix displays and Chronodot. All the major components for the project were purchased from Adafruit.
According to Atkins, the primary motivation for building the LED matrix clock was to learn Eagle and give OSH Park a shot.
“I wanted to make something with only components I’d already purchased, and that’s why it has a whole Arduino Micro attached to it even though a smaller board (or even just a lone microcontroller) would’ve been sufficient,” Atkins explained in a Google+ post.
“I didn’t get the displays lined up quite right, so there’s a small gap between them that looks obvious in this photo but isn’t so bad if you’re further away and looking at it head-on. But my learning for next time is to watch out for the positioning of odd-sized components.”
Atkins also noted that he just wired the red and green LEDs together, eschewing a bi-color approach for the current project and eliminating the need for doubling up on driver chips.
The total cost of the custom PCB? Around $45.
“The combination of the large-ish LED matrices plus the Arduino Micro and Chronodot forced the board to be on the larger side… It’s 3.94 by 2.25 inches,” he added.
Interested in learning more? You can check out Martin’s Google+ post here.