This is a little R-2R Digital to Analog converter breadboard adapter.
Having recently started playing with µControllers, I wanted to experiment with converting a digital signal into an analog voltage. The easiest way to accomplish this is by using an R-2R resistor ladder.
My ’99 Miata didn’t include an integral garage door opener but there were aftermarket modification kits available that inspired me to add one, with a few modifications, of course! Here is the write up that I created back then:
Tom Madracki, of Yorba Linda Miata, has an interesting garage door opener modification on his website. His opener modification activates the garage door opener whenever the high-beam headlights are turned on.
This is a write-up that I did for a local Miata club website back around ’99 or 2000. It includs the schematics but only a few photos, I didn’t take nearly as many back then as I’ve done for more recent projects. And, although the voice here is written as a set of instructions it has been a long time since I wrote this so use anything entirely at your own risk! Here’s the original write-up: