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Reads the value from a specified digital pin, either HIGH or LOW.
pin: the number of the digital pin you want to read (int)
HIGH or LOW
Sets pin 13 to the same value as pin 7, declared as an input.
int ledPin = 13; // LED connected to digital pin 13
int inPin = 7; // pushbutton connected to digital pin 7
int val = 0; // variable to store the read value
pinMode(ledPin, OUTPUT); // sets the digital pin 13 as output
pinMode(inPin, INPUT); // sets the digital pin 7 as input
val = digitalRead(inPin); // read the input pin
digitalWrite(ledPin, val); // sets the LED to the button's value
If the pin isn't connected to anything, digitalRead() can return either HIGH or LOW (and this can change randomly).
The analog input pins can be used as digital pins, referred to as A0, A1, etc.
Corrections, suggestions, and new documentation should be posted to the Forum.
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