Small afternoon project that I’ve been putting off for a long time: wiring a PIR motion sensor and LCD to my Arduino Uno, mostly just to finally try both the components at the same time.

The PIR sensor was pretty straightforward, three wires, but really janky because I don’t have a sensor shield or spare jumper wires (!). If the Neutral (white) wire isn’t connected well (it wasn’t) the digital pin will seesaw back and forth between Low and High with no rhyme or reason.

The LCD was a complete pain, again because I don’t have anything but some cheap wires and had to turn my breadboard into a rat’s nest. Also put one wire one spot to the right of where it should’ve been. “This little maneuver’s gonna cost us 51 years” type situation.

Anyway after that, wiring them both together was surprisingly painless, and with the help of some copy-pasted code I got it up and running quickly. Yippee, I have a little box that says MOTION DETECTED every time I walk by.