why does digitalRead of an LED turn it off?

Posted on Mon 17th, October 2022

• #1

callummclu

Whilst working on an addition ontop of UART.js ive found that digitalRead(LED) will turn off LED is this a bug or intended?
• #2

Gordon

That's intended - digitalRead automatically sets the pin state to input when you use it (in the same way you'd be surprised if digitalWrite didn't change the pin state to an output).

You can manually set the pin mode with pinMode though, and then it won't change state after that so you can do a digitalRead while leaving the LED on.

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