File content as of revision 3:f767577b7aab:

/*
 *  This VL53L0X Expansion board test application performs range measurements
 *  using the onboard embedded centre sensor, in singleshot, polling mode.
 *  Measured ranges are displayed on the on-board 4-digit display.
 *
 *  The User Blue button stops the current measurement and entire program,
 *  releasing all resources.
 *
 *  The Reset button can be used to restart the program.
 */

#include <string.h>
#include <stdio.h>

#include "mbed.h"
#include "x_nucleo_53l0a1.h"
#include "vl53l0x_class.h"

#define VL53L0_I2C_SDA   D14
#define VL53L0_I2C_SCL   D15

static X_NUCLEO_53L0A1 *board = NULL;
VL53L0X_RangingMeasurementData_t data_sensor_centre;
OperatingMode operating_mode;

/* flags that handle interrupt request */
bool int_stop_measure = false;

/* ISR callback function of the user blue button to stop program */
void stop_measure_irq(void)
{
    int_stop_measure = true;
}

/* On board 4 digit local display refresh */
void display_refresh(VL53L0X_RangingMeasurementData_t sensor_range_data)
{
    char str[10];

    if (sensor_range_data.RangeStatus == 0) {   // we have a valid range.
        sprintf(str, "%d", sensor_range_data.RangeMilliMeter);
    } else {
        sprintf(str, "%s", "----");
    }

    board->display->display_string(str);
}

/*=================================== Main ==================================
 Press the blue user button to stop measurements in progress
=============================================================================*/
int main()
{
#if USER_BUTTON == PC_13  // we are cross compiling for Nucleo-f401 
    InterruptIn stop_button(USER_BUTTON);
    stop_button.rise(&stop_measure_irq);
#endif

    DevI2C *device_i2c = new DevI2C(VL53L0_I2C_SDA, VL53L0_I2C_SCL);
    int status;

    /* creates the 53L0A1 expansion board singleton obj */
    board = X_NUCLEO_53L0A1::instance(device_i2c, A2, D8, D2);

    board->display->display_string("53L0");
    /* init the 53L0A1 expansion board with default values */
    status = board->init_board();
    if (status)
        printf("Failed to init board!\n\r");
    operating_mode = range_single_shot_polling;
    /* start the measure on sensor centre */
    status = board->sensor_centre->start_measurement(operating_mode, NULL);
    if (!status) {
        while (1) {   // infinite loop. can be broken by pressing Blue (User) button.
            status = board->sensor_centre->get_measurement(operating_mode, &data_sensor_centre);
            display_refresh(data_sensor_centre);
            if (int_stop_measure) {   // Blue Button isr was triggered
                status = board->sensor_centre->stop_measurement(operating_mode);   // stop the measure and exit
                int_stop_measure = false;
                printf("\nProgram stopped!\n\n\r");
                break;
            }
        }
    }
    board->display->display_string("BYE");
    delete board;
}