Page 106 - ARM Based Microcontroller Projects Using MBED

92 7. USING THE Mbed WITH SIMPLE PROJECTS

/*******************************************************************
EXTERNAL FLASHING LED
=====================
In this project an external LED is connected to GPIO port pin 10
of PORT C (PC_10) through a 390 ohm current limiting resistor. The
program flashes the LED quickly such that the ON time is 0.1 second
and the OFF time is 1 second. The net result is that the LED flashes
quickly
Author: Dogan Ibrahim
Date : August 2018
File : ExtLED
*********************************************************************/
#include "mbed.h"
DigitalOut LED(PC_10); // External LED at PC_10

#define ON 1 // ON = 1
#define OFF 0 // OFF = 0
#define ONTime 0.1 // ONTime = 0.1s
#define OFFTime 1.0 // OFFTime = 1.0s

int main()
{
while(1) // DO FOREVER
{
LED = ON; // LED ON
wait(ONTime); // Wait ONTime seconds
LED = OFF; // LED OFF
wait(OFFTime); // Wait OFFTime seconds
}
}
FIG. 7.23 Program listing.

7.7 PROJECT 4—ROTATING LEDs

7.7.1 Description
In this project 8 external LEDs are connected to PORT C the Nucleo-F411RE development
board. The LEDs turn ON/OFF in a rotating manner every second where only one LED is ON
at any time. Fig. 7.24 shows the LED pattern.

7.7.2 Aim

The aim of this project is to show how external LEDs can be connected to the Nucleo-
F411RE board.