File content as of revision 0:a521da10b15a:

#include "mbed.h"


DigitalIn sensorPin1(p5);
// variables:   
int counter = 0; // counter for the number of products passing through 
int sensorState1 = 0;    // current state of the sensor   
int lastSensorState1 = 0;  // previous state of the sensor 

// initialize serial communication:   
Serial pc(USBTX, USBRX);

DigitalOut myled(LED1);



int main() {
    while(1)
    {
        sensorState1 = sensorPin1; // read the pushbutton input pin:   
                 
        if (sensorState1 != lastSensorState1) // compare the buttonState to its previous state
        {
            // if the state has changed, check to see if it is a change from high to low or low to high             
            if (sensorState1 == 1){ // if the current state is HIGH then increment the counter   
                counter++;
                pc.printf("%f",counter);
            }
            
            else { // if the current state is LOW then the button       
                pc.printf("%f",counter);
            }
        }
        lastSensorState1 = sensorState1;
    }
}