As the weather is warming up here in Norway — my kids have gotten their bikes out. To make it more fun, both for them and me, I figured I’d build a series of traffic signals that they could play with.

I first started with a traffic light, simple — red, yellow and green. To control it I am using a Raspberry Pi Zero W, this will allow me to make it communicate on Wi-Fi and MQTT later.

I’m using Prometheus to monitor my home office and homelab, I figured it would be cool to have a stack light show the active warnings and alerts from Alertmanager. So I made a HAT (Hardware Attached on Top) for the Raspberry Pi to drive a five-colored stack light.

A control module for a green, yellow and red stack light, and signalling horn. Uses an AVR ATtiny2313 microcontroller.

My first “rack” was made of wood. It monitored, meaning displayed and alerted, on some metrics on my Linux server. And controlled a few lights and the alarm system in my room.

I really enjoyed making the computer control the lights.