2
\$\begingroup\$

I know there are other GPIO / Garage door related questions, but this is not a duplicate- I need to read the status of the garage door button, not a garage door sensor.

I would like to connect the garage door's button to a GPIO input on my Pi. I want to be able to trigger actions when someone pushes the button. I am able to read the status of a basic switch using this circuit I found. My concern is that when I connect a volt meter across the garage door button I see over 16 volts (presumably to drive the LED in the button?). I am concerned that if I connect my switch reading GPIO input circuit to the button, that 16 volts could fry my Pi. How can I read whether the button is open or closed, but protect my Pi from the voltage on the line?

I do also have a garage door magnetic switch sensor that I can read fine with my GPIO circuit, but my requirements include knowing when the button is pushed- not just whether the door is open or closed.

\$\endgroup\$
3
\$\begingroup\$

Is it possible that you are looking for an optocoupler?

\$\endgroup\$
  • \$\begingroup\$ I think it is. Just found that... \$\endgroup\$ – dgel Mar 2 '13 at 21:11

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.