Overview

This is my first custom design PCB build, that I built after learning electronics and AVR mCUs (microcontrollers). After learning & experimenting with ATtiny45, ATmega328p, etc on breadboard. I wanted to build something compact on PCB. And with the love for SMD LEDs I came up with this idea of creating a LED matrix keychain with WiFi connectivity to update the text on the keychain.

Overall it was fun and educational experience, and a beginning of something new!

Software architecture

I'm using here Esp's FreeRTOS-SDK, so no Arduino.

It was so fun writing the LED drivers all by myself from scratch!

Hardware

• ESP8266
• 2 8-bit SIPO Shift Registers 74LS164
• 63 0805 LEDs
• FTDI for programming the mCU