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+.. _arduino-digitalread:
+
+digitalRead()
+=============
+
+Description
+-----------
+
+Reads the value from a specified digital pin, either
+`HIGH <http://arduino.cc/en/Reference/Constants>`_ or
+`LOW <http://arduino.cc/en/Reference/Constants>`_.
+
+
+
+Syntax
+------
+
+digitalRead(pin)
+
+
+
+Parameters
+----------
+
+pin: the number of the digital pin you want to read (*int*)
+
+
+
+Returns
+-------
+
+`HIGH <http://arduino.cc/en/Reference/Constants>`_ or
+`LOW <http://arduino.cc/en/Reference/Constants>`_
+
+
+
+Example
+-------
+
+::
+
+
+ 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.
+
+
+
+Note
+----
+
+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.
+
+
+
+See also
+--------
+
+
+- `pinMode <http://arduino.cc/en/Reference/PinMode>`_\ ()
+- `digitalWrite <http://arduino.cc/en/Reference/DigitalWrite>`_\ ()
+- `Tutorial: Digital Pins <http://arduino.cc/en/Tutorial/DigitalPins>`_
+
+