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Reads the value from a specified pin, it will be either HIGH or LOW.
pin: the number of the pin you want to read. It has to be one of the digital pins of the board, thus it should be a number between 0 and 13. It could also be a variable representing a value in that range.
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 void setup() { pinMode(ledPin, OUTPUT); // sets the digital pin 13 as output pinMode(inPin, INPUT); // sets the digital pin 7 as input } void loop() { val = digitalRead(inPin); // read the input pin digitalWrite(ledPin, val); // sets the LED to the button's value }
Sets pin 13 to the same value as the pin 7, which is an input.
If the pin isn't connected to anything, digitalRead() can return either HIGH or LOW (and this can change randomly).
Corrections, suggestions, and new documentation should be posted to the Forum.
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