File content as of revision 6:44018e172a4a:

#include "mbed.h"
//#include "rgb_lcd.h"
//#include "PrintBuffer.h"

DigitalOut  myled1(LED1);
DigitalOut  myled2(LED2);
DigitalOut  myled3(LED3);
DigitalOut  myled4(LED4);

int main() {
//   lcd.begin(16, 2);
    while(1) {
 
        myled1 = 1; //left most LED turns ON, rest off
        myled2 = 0;
        myled3 = 0;
        myled4 = 0;
        
        wait(0.5); //1 sec wait time
        myled1 = 0;
        myled2 = 1; //2nd from left LED turns ON, rest off
        myled3 = 0;
        myled4 = 0;

        wait(0.5);
        myled1 = 0;
        myled2 = 0;
        myled3 = 1; //3rd from left LED turns ON, rest off
        myled4 = 0;
        
        wait(0.5);
        myled1 = 0;
        myled2 = 0;
        myled3 = 0;
        myled4 = 1; //4th from left (right most) LED turns ON, rest off
        wait(0.5);
       
    }
}