File content as of revision 0:f44522e28559:

#include "mbed.h"
#include "platform/mbed_thread.h"
 
using namespace std::chrono;
 
InterruptIn    user_button(USER_BUTTON);
DigitalOut     led(LED1);
 
bool           executeMainTask = false;
Timer          user_button_timer, loop_timer;
int            Ts_ms = 50;
 
void           button_fall();
void           button_rise();
 
/* input your stuff here */
AnalogIn       analogIn(PA_0);
float          dist = 0.0f;
 
int main()
{
    user_button.fall(&button_fall);
    user_button.rise(&button_rise);
    loop_timer.start();
 
    while (true) {
 
        loop_timer.reset();
 
        /* ------------- start hacking ------------- -------------*/
 
        if(executeMainTask) {
 
            dist = analogIn.read()*3.3f;
 
            /* do only output what's really necessary, outputting "Measured value in mV: "" within the loop is no good solution */           
            printf("Measured value in mV: %d\r\n", (static_cast<int>(dist * 1e3)));
 
            /* visual feedback that the main task is executed */
            led = !led;
 
        } else {
            led = 0;
        }
 
        /* ------------- stop hacking ------------- -------------*/
 
        int T_loop_ms = duration_cast<milliseconds>(loop_timer.elapsed_time()).count();
        int dT_loop_ms = Ts_ms - T_loop_ms;
        thread_sleep_for(dT_loop_ms);
    }
}
 
void button_fall()
{
    user_button_timer.reset();
    user_button_timer.start();
}
 
void button_rise()
{
    int t_button = duration_cast<milliseconds>(user_button_timer.elapsed_time()).count();
    user_button_timer.stop();
    if(t_button > 200) executeMainTask = !executeMainTask;
}