2020-10-12, 10:51 PM
(This post was last modified: 2020-10-12, 10:54 PM by seandepagnier.)
The resistor is mainly in case software on the pi somehow set the pin to output and then you pressed the button as well. A 27-47 ohm resistor won't protect this, I think 240 is the minimum for raspberry gpio.
Having a resistor for every key protects even if you press multiple keys at the same time when one pin is set to output high and the other low which is relatively unlikely.
So the resistor is only needed if the wrong software is running, because the right software all the pins are inputs.
Having a resistor for every key protects even if you press multiple keys at the same time when one pin is set to output high and the other low which is relatively unlikely.
So the resistor is only needed if the wrong software is running, because the right software all the pins are inputs.