pinMode

Configures the specified pin to behave either as an input or an output. See the description of digital pins for details on the functionality of the pins

void pinMode(uint8_t pin, uint8_t mode);

Parameters

pin - the number of the pin whose mode you wish to set
mode - INPUT, OUTPUT, or INPUT_PULLUP. (see the digital pins page for a more complete description of the functionality.)

Return Value

N/A

Remarks

As of Arduino 1.0.1, it is possible to enable the internal pullup resistors with the mode INPUT_PULLUP. Additionally, the INPUT mode explicitly disables the internal pullups.


The analog input pins can be used as digital pins, referred to as A0, A1, etc.

Requirements

wiring.h

Example

int ledPin = 13;                 // LED connected to digital pin 13

void setup()
{
  pinMode(ledPin, OUTPUT);      // sets the digital pin as output
}

void loop()
{
  digitalWrite(ledPin, HIGH);   // sets the LED on
  delay(1000);                  // waits for a second
  digitalWrite(ledPin, LOW);    // sets the LED off
  delay(1000);                  // waits for a second
}

Library

Arduino C Library Reference