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Use the DigitalOut interface to configure and control a digital output pin by setting the pin to logic level 0 or 1.

DigitalOut class reference

Public Member Functions
 DigitalOut (PinName pin)
 Create a DigitalOut connected to the specified pin. More...
 DigitalOut (PinName pin, int value)
 Create a DigitalOut connected to the specified pin. More...
void write (int value)
 Set the output, specified as 0 or 1 (int) More...
int read ()
 Return the output setting, represented as 0 or 1 (int) More...
int is_connected ()
 Return the output setting, represented as 0 or 1 (int) More...
DigitalOutoperator= (int value)
 A shorthand for write() More...
DigitalOutoperator= (DigitalOut &rhs)
 A shorthand for write() using the assignment operator which copies the state from the DigitalOut argument. More...
 operator int ()
 A shorthand for read() More...

DigitalOut hello, world

/* mbed Example Program
 * Copyright (c) 2006-2014 ARM Limited
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *     http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * See the License for the specific language governing permissions and
 * limitations under the License.
#include "mbed.h"

DigitalOut myled(LED1);

int main()
    // check that myled object is initialized and connected to a pin
    if(myled.is_connected()) {
        printf("myled is initialized and connected!\n\r");

    // Blink LED
    while(1) {
        myled = 1;          // set LED1 pin to high
        printf("myled = %d \n\r", (uint8_t)myled );

        myled.write(0);     // set LED1 pin to low
        printf("myled = %d \n\r",myled.read() );

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