Example 1

Connect as follows

1. Observe that LED1 starts blinking when the free end of the jumper wire in contact with the free end of the resistor.
2. When the connection breaks, the blinking stops.

#include "mbed.h"

DigitalIn  enable(p30);
DigitalOut myled(LED1);

int main() {
    while (1)
        if (enable) {
            myled = !myled;
            wait(0.25);
        }
}

Example 2

Connect as follows

1. If the button is pressed, the digital input enable becomes false (0V). LED1 starts blinking.
2. When the button is released, the digital input enable becomes true (+3.3V). LED1 stop blinking.

#include "mbed.h"

DigitalIn  enable(p30);
DigitalOut myled(LED1);

int main() {
    while (1)
        if (!enable) {
            myled = !myled;
            wait(0.25);
        }
}

Example 3

Connect as follows

1. If the button is pressed, the digital input enable becomes true (+3.3V). LED1 starts blinking.
2. When the button is released, the digital input enable becomes false (0V). LED1 stop blinking.

#include "mbed.h"

DigitalIn  enable(p30);
DigitalOut myled(LED1);

int main() {
    while (1)
        if (enable) {
            myled = !myled;
            wait(0.25);
        }
}

Example 4

Using internal pull-up resistor, we can save external resistor and connection.

Connect as follows

1. If the button is pressed, the digital input enable becomes false (0V). LED1 starts blinking.
2. When the button is released, the digital input enable becomes true (+3.3V). LED1 stop blinking.

#include "mbed.h"

DigitalIn  enable(p30);
DigitalOut myled(LED1);

int main() {
    while (1)
        if (!enable) {
            myled = !myled;
            wait(0.25);
        }
}

Example 5

Connect as follows

1. If the button is pressed, the digital input enable becomes true (+3.3V). LED1 starts blinking.
2. When the button is released, the digital input enable becomes false (0V). LED1 stop blinking.

#include "mbed.h"

DigitalIn  enable(p30);
DigitalOut myled(LED1);

int main() {
    while (1)
        if (enable) {
            myled = !myled;
            wait(0.25);
        }
}