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By polarbeared
#190015
Hi everyone,

I have a university assignment due after tomorrow, so this is very last minute. The intentions of my assignment was to get a garage door to open by using the GPIO pins on an RPi2. I know this has been covered plenty of times on the internet, but most of them are using relay switches or independent power supplies and things I don't understand.

I have Jaycar Electronics (Australia) about 20 minutes drive away. If cell button remote control, and the contacts of the open switch soldered with a wire either side, what parts do I need to get this to work from a command line?

Optocouplers, relays and transistors are about as far as I got, but I don't have enough electronics knowledge to know what I need to wire.

Most sources online seem to include an independent power supply, but I really can't understand what use that serves when I thought I was only joining a circuit by supplying an optocoupler with the Pi's GPIO 3.3v output.

Please help! I'll try my best to understand wiring diagrams.