Digital I/O

This library is for configuring the digital signal (HIGH/LOW) to function as either input or output.

pinMode

Description
Configures the specified pin to behave either as an input or an output.
Syntax
pinMode(pin, mode)
Parameters
pin: The number of the pin to be set.
mode:
   INPUT
   OUTPUT
   INPUT_PULLUP (pullup then input)
   OUTPUT_HIGH (enable 2 times current)
   OUTPUT_OPENDRAIN
Returns
None

digitalWrite

Description
Writes a HIGH or LOW value to a digital pin.
Syntax
digitalWrite(uint8_t pin, uint8_t value)
Parameters
pin: The pin number
value: HIGH or LOW
Returns
None

digitalRead

Description
Reads the value from a specified digital pin, either HIGH or LOW.
Syntax
digitalRead(uint8_t pin)
Parameters
pin: The number of the digital pin you want to read
Returns
HIGH or LOW

Sample Program

Sample for digitalWrite and digitalRead.


#include <Arduino.h>
void setup()
{
    pinMode(PIN_LED0, OUTPUT);
    pinMode(PIN_LED1, OUTPUT);
    pinMode(PIN_SW, INPUT);
}
  
void loop()
{
    if(digitalRead(PIN_SW) == 0){
        digitalWrite(PIN_LED0, HIGH);
        digitalWrite(PIN_LED1, LOW);
    } else {
        digitalWrite(PIN_LED1, HIGH);
        digitalWrite(PIN_LED0, LOW);
    }
}