File content as of revision 11:c6f95a42d4d7:

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#ifndef __VL53L0X_CLASS_H
#define __VL53L0X_CLASS_H

/* Includes ------------------------------------------------------------------*/
#include "mbed.h"
#include "pinmap.h"
#include "PinNames.h"
#include "VL53L0X_def.h"

/* Classes -------------------------------------------------------------------*/
/** Class representing a VL53L0 sensor component
 */
class VL53L0X 
{
public:
    /* Device data made accessible for further usage */
    TVL53L0X_DeviceInfo Device_Info;

public: 
	/******************************************************************************/
	/****************** Public Initialization Methods     *************************/
	/******************************************************************************/

    /** Constructor
     * @param[in] &i2c device I2C to be used for communication
     * @param[in] &pin_gpio1 pin Mbed InterruptIn PinName to be used as component GPIO_1 INT
     * @param[in] dev_addr device address, 0x29 by default
     */
    VL53L0X(I2C *i2c, DigitalOut *pin, PinName pin_gpio1, 
        uint8_t dev_addr = VL53L0X_DEFAULT_ADDRESS) : _dev_i2c(i2c), _gpio0(pin)
    {   I2cDevAddr = dev_addr;
        if (pin_gpio1 != NC) { _gpio1Int = new InterruptIn(pin_gpio1); } 
           else { _gpio1Int = NULL;  }
    }

    /**
     * @brief       Turns on, checks the ID, Set new device address, 
     *              Initialize the calss, and the sensor with default values
     *
     * After completion the device will answer to the address new_addr.
     * This new_addr should be set to individual values when several devices are used in parallel
     * before using the individual sensors.
     * When a single device us used, there is no need to set new_addr.
     * @return      VL53L0X_Error   	= 0 on success
     */
    VL53L0X_Error Start_Sensor(uint8_t new_addr = VL53L0X_DEFAULT_ADDRESS);

    /**
     * @brief       PowerOff the sensor with the XShutdown Pin
     */
    void Power_Off(void)
    {	if (_gpio0) { *_gpio0 = 0; }   wait_ms(1); }


    /** Destructor  */
    virtual ~VL53L0X()
    {  if (_gpio1Int != NULL) { delete _gpio1Int; } }


private: 
	/******************************************************************************/
	/****************** Private Initialization Methods    *************************/
	/******************************************************************************/

    /**
     * @brief One time device initialization
     *
     * To be called once and only once after device is brought out of reset
     * (Chip enable) and booted see @a void WaitDeviceBooted()
     *
     * @par Function Description
     * When not used after a fresh device "power up" or reset, it may return
     * @a #VL53L0X_ERROR_CALIBRATION_WARNING meaning wrong calibration data
     * may have been fetched from device that can result in ranging offset error\n
     * If application cannot execute device reset or need to run VL53L0X_DataInit
     * multiple time then it  must ensure proper offset calibration saving and
     * restore on its own by using @a VL53L0X_GetOffsetCalibrationData() on first
     * power up and then @a VL53L0X_SetOffsetCalibrationData() in all subsequent init
     * This function will change the VL53L0X_State from VL53L0X_STATE_POWERDOWN to
     * VL53L0X_STATE_WAIT_STATICINIT.
     *
     * @note This function accesses to the device
     * 
     * @return  None; instead check class Field "ErrState"
     */
    void Data_init();
 
    /**
     * @brief Reads the Device information for given Device
     *
     * @note This function is called once at Sensor Init, then all device info
     *    available in the Device_Info Structure
     * 
     * @return   Device_Info  Structure is filled with device info for the Device
     *           Also check and fix errors reported Field "ErrState"   */
    void Fill_device_info();
    
public:
    /**
     * @brief       Start the measure indicated by operating mode
     * @param[in]   operating_mode specifies requested measure
     * @param[in]   fptr specifies call back function must be !NULL in case of interrupt measure
     */
    VL53L0X_Error Start_Measurement(TOperatingMode operating_mode, 
                   void (*fptr)(void));

    /**
     * @brief       Get results for the measure indicated by operating mode
     * @param[in]   operating_mode specifies requested measure results
     * @result       TRangeResults The MeasureData_t structure with all results
     */
    TRangeResults Get_Measurement(TOperatingMode operating_mode);

    /**
     * @brief       Stop the currently running measure indicate by operating_mode
     * @param[in]   operating_mode specifies requested measure to stop
     "0" on success
     */
    VL53L0X_Error Stop_Measurement(TOperatingMode operating_mode);

    /**
     * @brief     Interrupt handling func to be called by user after an INT is occourred
     * @param[in] operating_mode  Opeating_mode indicating the in progress measure
     * @result    TRangeResults   The Measurement Data structure given back
     */
    TRangeResults Handle_irq(TOperatingMode operating_mode);

    /**
     * @brief       Enable interrupt measure IRQ
     */
    void Enable_interrupt_measure_detection_irq(void)
    {  if (_gpio1Int != NULL) { _gpio1Int->enable_irq(); }  }

    /**
     * @brief       Disable interrupt measure IRQ
     "0" on success
     */
    void Disable_interrupt_measure_detection_irq(void)
    {  if (_gpio1Int != NULL) { _gpio1Int->disable_irq(); }  }

    /**
     * @brief       Attach a function to call when an interrupt is detected, i.e. measurement is ready
     * @param[in]   fptr pointer to call back function to be called whenever an interrupt occours
     "0" on success
     */
    void Attach_interrupt_measure_detection_irq(void (*fptr)(void))
    {   if (_gpio1Int != NULL) { _gpio1Int->rise(fptr);  }    }

    /** Wrapper functions */
    /** @defgroup api_init Init functions
     *  @brief    API init functions
     *  @ingroup  api_hl
     *  @{
     */

    /**
      * @brief  Prepare device for operation
      * @par Function Description
      * Does static initialization and reprogram common default settings \n
      * Device is prepared for new measure, ready single shot ranging or ALS typical polling operation\n
      * After prepare user can : \n
      * @li Call other API function to set other settings\n
      * @li Configure the interrupt pins, etc... \n
      * @li Then start ranging or ALS operations in single shot or continuous mode
      *
      * @param void
      * @return  "0" on success
      */
    VL53L0X_Error Prepare();

    /**
    * @brief Start continuous ranging mode
    *
    * @details End user should ensure device is in idle state and not already running
    * @return  "0" on success
    */
    void Range_start_continuous_mode()
    {	Set_device_mode( VL53L0X_DEVICEMODE_CONTINUOUS_RANGING);
        if (ErrState == VL53L0X_OK) {  Start_Measurement();  }
    }

    /**
     * @brief Get ranging result and only that
     *
     * @par Function Description
     * Unlike @a Get_ranging_results() this function only retrieves the range in millimeter \n
     * It does any required up-scale translation\n
     * It can be called after success ErrState polling or in interrupt mode \n
     * @warning these function is not doing wrap around filtering \n
     * This function doesn't perform any data ready check!
     *
     * @param p_data  Pointer to range distance
       "0" on success
     */
    uint32_t Get_distance();

    /** @}  */



    /**
     * @brief Do basic device init (and eventually patch loading)
     * This function will change the VL53L0X_State from
     * VL53L0X_STATE_WAIT_STATICINIT to VL53L0X_STATE_IDLE.
     * In this stage all default setting will be applied.
     *
     * @note This function Access to the device
     *
     * 
     * @return  None; instead check class Field "ErrState"
     */
    void Static_init();

    /**
     * @brief Perform Reference Calibration
     *
     * @details Perform a reference calibration of the Device.
     * This function should be run from time to time before doing
     * a ranging measurement.
     * This function will launch a special ranging measurement, so
     * if interrupt are enable an interrupt will be done.
     * This function will clear the interrupt generated automatically.
     *
     * @warning This function is a blocking function
     *
     * @note This function Access to the device
     *
     * 
     * @param   p_vhv_settings       Pointer to vhv settings parameter.
     * @param   p_phase_cal          Pointer to PhaseCal parameter.
     * @param   get_data_enable      1 to enable to get the data
     * @return  None; instead check class Field "ErrState"
     */
    void Perf_Ref_calibration(
            uint8_t *p_vhv_settings, uint8_t *p_phase_cal, uint8_t get_data_enable);

    /**
     * @brief Get Reference Calibration Parameters
     *
     * @par Function Description
     * Get Reference Calibration Parameters.
     *
     * @note This function Access to the device
     *
     * 
     * @param   p_vhv_settings                 Pointer to VHV parameter
     * @param   p_phase_cal                    Pointer to PhaseCal Parameter
     * @return  None; instead check class Field "ErrState"            
     */
    void Get_Ref_calibration(
            uint8_t *p_vhv_settings, uint8_t *p_phase_cal);

    void Set_Ref_calibration(
            uint8_t vhv_settings, uint8_t phase_cal);

    /**
     * @brief Performs Reference SPAD Management
     *
     * @par Function Description
     * The reference SPAD initialization procedure determines the minimum amount
     * of reference SPADS to be enables to achieve a target reference signal rate
     * and should be performed once during initialization.
     *
     * @note This function Access to the device
     *
     * @note This function change the device mode to
     * VL53L0X_DEVICEMODE_SINGLE_RANGING
     *
     * 
     * @param   ref_SPAD_count               Reports ref SPAD Count
     * @param   is_aperture_SPADS            Reports if SPADS are of type
     *                                       aperture or non-aperture.
     *                                       1:=aperture, 0:=Non-Aperture
     * @return  None; instead check class Field "ErrState"       
     * @return  VL53L0X_ERROR_REF_SPAD_INIT  Error in the Ref SPAD procedure.
     */
    void Perf_Ref_SPAD_management(
            uint32_t *ref_SPAD_count, uint8_t *is_aperture_SPADS);

    /**
     * @brief Applies Reference SPAD configuration
     *
     * @par Function Description
     * This function applies a given number of reference SPADS, identified as
     * either Aperture or Non-Aperture.
     * The requested SPAD count and type are stored within the device specific
     * parameters data for access by the host.
     *
     * @note This function Access to the device
     *
     * 
     * @param   refSPADCount                 Number of ref SPADS.
     * @param   is_aperture_SPADS            Defines if SPADS are of type
     *                                       aperture or non-aperture.
     *                                       1:=aperture, 0:=Non-Aperture
     * @return  None; instead check class Field "ErrState"       
     * @return  VL53L0X_ERROR_REF_SPAD_INIT  Error in the in the reference
     *                                       SPAD configuration.
     */
    void Set_Reference_SPADS(
            uint32_t refSPADCount, uint8_t is_aperture_SPADS);

    /**
     * @brief Retrieves SPAD configuration
     *
     * @par Function Description
     * This function retrieves the current number of applied reference SPADS
     * and also their type : Aperture or Non-Aperture.
     *
     * @note This function Access to the device
     *
     * 
     * @param   p_SPAD_count                 Number ref SPAD Count
     * @param   p_is_aperture_SPADS          Reports if SPADS are of type
     *                                       aperture or non-aperture.
     *                                       1:=aperture, 0:=Non-Aperture
     * @return  None; instead check class Field "ErrState"       
     * @return  VL53L0X_ERROR_REF_SPAD_INIT  Error in the in the reference
     *                                       SPAD configuration.
     */
    void Get_Reference_SPADS(
            uint32_t *p_SPAD_count, uint8_t *p_is_aperture_SPADS);

    /**
     * @brief Get part to part calibration offset
     *
     * @par Function Description
     * Should only be used after a successful call to @a VL53L0X_DataInit to backup
     * device NVM value
     *
     * @note This function Access to the device
     *
     * @param   p_Offset_Cal_um   
     * @return  int32_t; Return part to part calibration offset from device (microns), also check class Field "ErrState"                           
     */
    int32_t Get_Offset_Cal_um();
    /**
     * Set or over-hide part to part calibration offset
     * \sa VL53L0X_DataInit()   VL53L0X_GetOffsetCalibrationData_um()
     *
     * @note This function Access to the device
     *
     * @param   p_Offset_Cal_um    Offset (microns)
     * @return  None; instead check class Field "ErrState"                           
     */
    void Set_Offset_Cal_um(  int32_t Offset_Cal_um  );

    void Perf_offset_calibration( TFP1616 cal_distance_milli_meter,
            int32_t *p_offset_um);

    void Perf_xtalk_calibration(  TFP1616 xtalk_cal_distance,
            TFP1616 *p_Xtalk_CompRate_MHz);

    /**
     * @brief Perform XTalk Measurement
     *
     * @details Measures the current cross talk from glass in front
     * of the sensor.
     * This functions performs a histogram measurement and uses the results
     * to measure the crosstalk. For the function to be successful, there
     * must be no target in front of the sensor.
     *
     * @warning This function is a blocking function
     *
     * @warning This function is not supported when the final range
     * vcsel clock period is set below 10 PCLKS.
     *
     * @note This function Access to the device
     *
     * 
     * @param   timeout_ms             Histogram measurement duration.
     * @param   p_xtalk_per_SPAD       Output parameter containing the crosstalk
     *                                 measurement result, in MHz/SPAD.
     *                                 Format fixpoint 16:16.
     * @param   p_ambient_too_high     Output parameter which indicate that
     *                                 pXtalkPerSPAD is not good if the Ambient
     *                                 is too high.
     * @return  None; instead check class Field "ErrState" 
     * @return  VL53L0X_ERROR_INVALID_PARAMS vcsel clock period not supported
     *                                 for this operation.
     *                                 Must not be less than 10PCLKS.
     */
    void Perf_xtalk_measurement(
            uint32_t timeout_ms, TFP1616 *p_xtalk_per_SPAD,
            uint8_t *p_ambient_too_high);

    /**
     * @brief Enable/Disable Cross talk compensation feature
     *
     * @note This function is not Implemented.
     * Enable/Disable Cross Talk by set to zero the Cross Talk value
     * by using @a VL53L0X_SetXtalk_CompRate_MHz().
     *
     * 
     * @param  xtalk_compensation_enable    Cross talk compensation
     *                                       to be set 0=disabled else = enabled
     * @return VL53L0X_ERROR_NOT_IMPLEMENTED Not implemented
     */
    void Set_xtalk_compensation_enable(
            uint8_t xtalk_compensation_enable);

     /**
     * @brief Set Cross talk compensation rate
     *
     * @par Function Description
     * Set Cross talk compensation rate.
     *
     * @note This function Access to the device
     *
     * 
     * @param   Xtalk_CompRate_MHz   Compensation rate in
     *                                              Mega counts per second
     *                                              (16.16 fix point) see
     *                                              datasheet for details
     * @return  None; instead check class Field "ErrState"              
     */
    void Set_Xtalk_CompRate_MHz(  TFP1616 Xtalk_CompRate_MHz );

    /**
     * @brief Get Cross talk compensation rate
     *
     * @par Function Description 
     * Get Cross talk compensation rate.
     *
     * @note This function Access to the device
     *
     * 
     * @param   p_Xtalk_CompRate_MHz  Pointer to Compensation rate
     *                                              in Mega counts per second
     *                                              (16.16 fix point) see
     *                                              datasheet for details
     * @return  None; instead check class Field "ErrState"                
     */
     
    void Get_Xtalk_CompRate_MHz(
            TFP1616 *p_Xtalk_CompRate_MHz);

    /**
     * @brief  Set a new device mode
     * @par Function Description
     * Set device to a new mode (ranging, histogram ...)
     *
     * @note This function doesn't Access to the device
     *
     * 
     * @param   device_mode           New device mode to apply
     *                                Valid values are:
     *                                VL53L0X_DEVICEMODE_SINGLE_RANGING
     *                                VL53L0X_DEVICEMODE_CONTINUOUS_RANGING
     *                                VL53L0X_DEVICEMODE_CONTINUOUS_TIMED_RANGING
     *                                VL53L0X_DEVICEMODE_SINGLE_HISTOGRAM
     *                                VL53L0X_HISTOGRAMMODE_REFERENCE_ONLY
     *                                VL53L0X_HISTOGRAMMODE_RETURN_ONLY
     *                                VL53L0X_HISTOGRAMMODE_BOTH
     *
     *
     * @return  None; instead check class Field "ErrState"           
     * @return  VL53L0X_ERROR_MODE_NOT_SUPPORTED This error occurs when
     *                                           DeviceMode is not in the
     *                                           supported list
     */
    void Set_device_mode( VL53L0X_DeviceModes device_mode);

    /**
    * @brief Get current configuration for GPIO pin for a given device
    *
    * @note This function Access to the device
    *
    * 
    * @param   pin                   ID of the GPIO Pin
    * @param   p_device_mode         Pointer to Device Mode associated to the Gpio.
    * @param   p_functionality       Pointer to Pin functionality.
    *                                Refer to ::TGPIO_Func
    * @param   p_polarity            Pointer to interrupt polarity.
    *                                Active high or active low see
    *                                ::VL53L0X_InterruptPolarity
    * @return  None; instead check class Field "ErrState"
    * @return  VL53L0X_ERROR_GPIO_NOT_EXISTING           Only Pin=0 is accepted.
    * @return  VL53L0X_ERROR_GPIO_FUNC_NOT_SUPPORTED
    *          This error occurs
    *          when Funcionality programmed is not in the supported list:
    *                      Supported value are:
    *                      GPIO_FUNC_OFF,
    *                      GPIO_FUNC_THRESHOLD_CROSSED_LOW,
    *                      GPIO_FUNC_THRESHOLD_CROSSED_HIGH,
    *                      GPIO_FUNC_THRESHOLD_CROSSED_OUT,
    *                      GPIO_FUNC_NEW_MEASURE_READY
    */
    void Get_gpio_config( uint8_t pin, VL53L0X_DeviceModes *p_device_mode,
                                          TGPIO_Func *p_functionality,
                                          VL53L0X_InterruptPolarity *p_polarity);

    /**
     * @brief Set the configuration of GPIO pin for a given device
     *
     * @note This function Access to the device
     * 
     * @param   pin                   ID of the GPIO Pin
     * @param   functionality         Select Pin functionality.
     *  Refer to ::TGPIO_Func
     * @param   device_mode            Device Mode associated to the Gpio.
     * @param   polarity              Set interrupt polarity. Active high
     *   or active low see ::VL53L0X_InterruptPolarity
     * @return  None; instead check class Field "ErrState"                        
     * @return  VL53L0X_ERROR_GPIO_NOT_EXISTING               Only Pin=0 is accepted.
     * @return  VL53L0X_ERROR_GPIO_FUNC_NOT_SUPPORTED    This error occurs
     * when Functionality programmed is not in the supported list:
     *                             Supported value are:
     *                             	GPIO_FUNC_OFF,
     *                             	GPIO_FUNC_THRESHOLD_CROSSED_LOW,
     *                             	GPIO_FUNC_THRESHOLD_CROSSED_HIGH,
     *								GPIO_FUNC_THRESHOLD_CROSSED_OUT,
     *                              GPIO_FUNC_NEW_MEASURE_READY
     */
    void Set_GPIO_config( VL53L0X_DeviceModes device_mode, 
         TGPIO_Func functionality,  VL53L0X_InterruptPolarity polarity);

    /**
     * @brief Start device measurement
     *
     * @details Started measurement will depend on device parameters set through
     * @a VL53L0X_SetParameters()
     * This is a non-blocking function.
     * This function will change the VL53L0X_State from VL53L0X_STATE_IDLE to
     * VL53L0X_STATE_RUNNING.
     *
     * @note This function Access to the device
     *

     * 
     * @return  None; instead check class Field "ErrState"              
     * @return  VL53L0X_ERROR_MODE_NOT_SUPPORTED    This error occurs when
     * DeviceMode programmed with @a VL53L0X_SetDeviceMode is not in the supported
     * list:
     *                                   Supported mode are:
     *                                   VL53L0X_DEVICEMODE_SINGLE_RANGING,
     *                                   VL53L0X_DEVICEMODE_CONTINUOUS_RANGING,
     *                                   VL53L0X_DEVICEMODE_CONTINUOUS_TIMED_RANGING
     * @return  VL53L0X_ERROR_TIME_OUT    Time out on start measurement
     */
    void Start_Measurement();

    /**
     * @brief Stop device measurement
     *
     * @details Will set the device in standby mode at end of current measurement\n
     *          Not necessary in single mode as device shall return automatically
     *          in standby mode at end of measurement.
     *          This function will change the VL53L0X_State from VL53L0X_STATE_RUNNING
     *          to VL53L0X_STATE_IDLE.
     *
     * @note This function Access to the device
     *
     * 
     * @return  None; instead check class Field "ErrState"
     */
    void Stop_Measurement();

    /**
     * @brief Return device stop completion ErrState
     *
     * @par Function Description
     * Returns stop completiob ErrState.
     * User shall call this function after a stop command
     *
     * @note This function Access to the device
     *
     * 
     * @return   p_stop_status            Pointer to ErrState variable to update
     *                                    Also instead check class Field "ErrState"  
     */
    uint8_t Get_Stop_Completed( );

    /**
     * @brief Return Measurement is Ready
     *
     * @par Function Description
     * This function indicate that a measurement data is ready.
     * This function check if interrupt mode is used then check is done accordingly.
     * If perform function clear the interrupt, this function will not work,
     * like in case of @a VL53L0X_PerformSingleRangingMeasurement().
     * The previous function is blocking function, VL53L0X_GetMeasurementDataReady
     * is used for non-blocking capture.
     *
     * @note This function Access to the device
     *
     * 
     * @return   uint8_t     Is Measurement Ready 0= not ready, 1 = ready
     * 					     Also check class Field "ErrState"  
     */
    uint8_t Get_Measurement_Ready();

    /**
     * @brief Retrieve the measurements from device for a given setup
     *
     * @par Function Description
     * Get data from last successful Ranging measurement
     * @warning USER should take care about  @a VL53L0X_GetNumberOfROIZones()
     * before get data.
     * Device will fill a NumberOfROIZones times the corresponding data
     * structure used in the measurement function.
     *
     * @note This function Access to the device
     *
     * 
     * @param   p_ranging_results  Pointer to the data structure to fill up.
     * @return  None; instead check class Field "ErrState"    
     */
    void Get_ranging_results(
            TRangeResults *p_ranging_results);

    /**
     * @brief Clear given system interrupt condition
     *
     * @par Function Description
     * Clear given interrupt(s) cause by writing into register #SYSINT_CLEAR register.
     *
     * @note   This function Access to the device
     * 
     * @param   interrupt_mask        Which interrupt source to clear. Use any combinations of #INTERRUPT_CLEAR_RANGING , #INTERRUPT_CLEAR_ALS , #INTERRUPT_CLEAR_ERROR.
     * @return  None; instead check class Field "ErrState"
     * @return  VL53L0X_ERROR_INTERRUPT_NOT_CLEARED    Cannot clear interrupts
     */
     void Clear_interrupt_mask( uint32_t interrupt_mask);

    /**
     * @brief Return device interrupt ErrState
     *
     * @par Function Description
     * Returns currently raised interrupts by the device.
     * User shall be able to activate/deactivate interrupts through
     * @a VL53L0X_SetGpioConfig()
     *
     * @note This function Access to the device
     *
     * 
     * @param   p_interrupt_mask_status   Pointer to ErrState variable to update
     * @return  None; instead check class Field "ErrState"
     */
    void Get_interrupt_mask_status(  uint32_t *p_interrupt_mask_status);

    /**
     * @brief Performs a single ranging measurement and retrieve the ranging
     * measurement data
     *
     * @par Function Description
     * This function will change the device mode to VL53L0X_DEVICEMODE_SINGLE_RANGING
     * with @a VL53L0X_SetDeviceMode(),
     * It performs measurement with @a VL53L0X_PerformSingleMeasurement()
     * It get data from last successful Ranging measurement with
     * @a VL53L0X_GetRangingMeasurementData.
     * Finally it clear the interrupt with @a VL53L0X_ClearInterruptMask().
     *
     * @note This function Access to the device
     *
     * @note This function change the device mode to
     * VL53L0X_DEVICEMODE_SINGLE_RANGING
     *
     * 
     * @param   p_ranging_results   Pointer to the data structure to fill up.
     * @return  None; instead check class Field "ErrState"     
     */
    void Perf_single_ranging_measurement(
            TRangeResults *p_ranging_results);

    /**
     * @brief Single shot measurement.
     *
     * @par Function Description
     * Perform simple measurement sequence (Start measure, Wait measure to end,
     * and returns when measurement is done).
     * Once function returns, user can get valid data by calling
     * VL53L0X_GetRangingMeasurement or VL53L0X_GetHistogramMeasurement
     * depending on defined measurement mode
     * User should Clear the interrupt in case this are enabled by using the
     * function VL53L0X_ClearInterruptMask().
     *
     * @warning This function is a blocking function
     *
     * @note This function Access to the device
     *
     * 
     * @return  None; instead check class Field "ErrState"
     */
    void Perf_single_measurement();

    /**
    * @brief Read current ErrState of the error register for the selected device
    *
    * @note This function Access to the device
    *
    * @param   p_device_error_status    Pointer to current error code of the device
    * @return  None; instead check class Field "ErrState" 
    */
    void Get_device_error_status(TDevError *p_device_error_status);

    /**
    * @brief Human readable error string for a given Error Code
    *
    * @note This function doesn't access to the device
    *
    * @param   error_code           The error code as stored on ::TDevError
    * @param   p_device_error_string  The error string corresponding to the ErrorCode
    * @return  None; instead check class Field "ErrState"
    */
    void Get_device_error_string(TDevError error_code, char *p_device_error_string);

    void Get_total_SIG_rate( TRangeResults *p_ranging_results,
            TFP1616 *p_total_SIG_rate_mcps);

    TFP1616 Get_total_xtalk_rate( TRangeResults *p_ranging_results);
            
    /**
     * @brief Get Ranging Timing Budget in microseconds
     *
     * @par Function Description
     * Returns the programmed the maximum time allowed by the user to the
     * device to run a full ranging sequence for the current mode
     * (ranging, histogram, ASL ...)
     *
     * @note This function Access to the device
     *
     * 
     * @return   uint32_t   Max measurement time in microseconds.
     *                                   Valid values are:
     *                                   >= 17000 microsecs when wraparound enabled
     *                                   >= 12000 microsecs when wraparound disabled
     *   						Also check class Field "ErrState"                            
     */
    uint32_t Get_Measure_Time_Budget_us();

    /**
     * @brief Set Ranging Timing Budget in microseconds
     *
     * @par Function Description
     * Defines the maximum time allowed by the user to the device to run a
     * full ranging sequence for the current mode (ranging, histogram, ASL ...)
     *
     * @note This function Access to the device
     *
     * 
     * @param Measure_Time_Budget_us  Max measurement time in
     * microseconds.
     *                                   Valid values are:
     *                                   >= 17000 microsecs when wraparound enabled
     *                                   >= 12000 microsecs when wraparound disabled
     * @return  None; instead check class Field "ErrState"         
     * @return  VL53L0X_ERROR_INVALID_PARAMS   This error is returned if
     MeasurementTimingBudgetMicroSeconds out of range
     */
    void Set_Measure_Time_Budget_us( uint32_t Measure_Time_Budget_us);

    /**
     * @brief  Get specific limit check enable state
     *
     * @par Function Description
     * This function get the enable state of a specific limit check.
     * The limit check is identified with the limit_check_id.
     *
     * @note This function Access to the device
     *
     * 
     * @param   limit_check_id                  Limit Check ID
     *  (0<= limit_check_id < VL53L0X_GetNumberOfLimitCheck() ).
     * @return   uint8_t      Check limit enable value.
     *  if 1 the check limit
     *        corresponding to limit_check_id is Enabled
     *  if 0 the check limit
     *        corresponding to limit_check_id is disabled
     * @return  also check class Field "ErrState"         
     * @return  VL53L0X_ERROR_INVALID_PARAMS   This error is returned when limit_check_id value is out of range.
     */
    uint8_t Get_limit_chk_en( uint16_t limit_check_id);

    /**
     * @brief  Enable/Disable a specific limit check
     *
     * @par Function Description
     * This function Enable/Disable a specific limit check.
     * The limit check is identified with the limit_check_id.
     *
     * @note This function doesn't Access to the device
     * 
     * @param   limit_check_id         Limit Check ID
     *  (0<= limit_check_id < VL53L0X_GetNumberOfLimitCheck() ).
     * @param   limit_chk_en           if 1 the check limit corresponding to limit_check_id is Enabled
     *                                 if 0 the check limit corresponding to limit_check_id is disabled
     * @return  None; instead check class Field "ErrState"         
     * @return  VL53L0X_ERROR_INVALID_PARAMS   This error is returned
     *  when limit_check_id value is out of range.
     */
    void Set_limit_chk_en( uint16_t limit_check_id, uint8_t limit_chk_en);

    /**
     * @brief  Get a specific limit check value
     *
     * @par Function Description
     * This function get a specific limit check value from device then it updates
     * internal values and check enables.
     * The limit check is identified with the limit_check_id.
     *
     * @note This function Access to the device
     *
     * 
     * @param   limit_check_id                  Limit Check ID
     *  (0<= limit_check_id < VL53L0X_GetNumberOfLimitCheck() ).
     * @return  TFP1616         Limit  check Value for a given limit_check_id.
     * @return  Also check class Field "ErrState";returned VL53L0X_ERROR_INVALID_PARAMS
     *          when limit_check_id value is out of range.  
     */
    TFP1616 Get_limit_chk_val( uint16_t limit_check_id);

    /**
     * @brief  Set a specific limit check value
     *
     * @par Function Description
     * This function set a specific limit check value.
     * The limit check is identified with the limit_check_id.
     *
     * @note This function Access to the device
     * 
     * @param   limit_check_id                  Limit Check ID
     *  (0<= limit_check_id < VL53L0X_GetNumberOfLimitCheck() ).
     * @param   limit_chk_val               Limit check Value for a given
     * limit_check_id
     * @return  None; instead check class Field "ErrState"         
     * @return  VL53L0X_ERROR_INVALID_PARAMS   This error is returned when either
     *  limit_check_id or LimitCheckValue value is out of range.
     */
    void Set_limit_chk_val( uint16_t limit_check_id, TFP1616 limit_chk_val);

    /**
     * @brief  Get the current value of the signal used for the limit check
     *
     * @par Function Description
     * This function get a the current value of the signal used for the limit check.
     * To obtain the latest value you should run a ranging before.
     * The value reported is linked to the limit check identified with the
     * limit_check_id.
     *
     * @note This function Access to the device
     * 
     * @param   limit_check_id                  Limit Check ID
     *  (0<= limit_check_id < VL53L0X_GetNumberOfLimitCheck() ).
     * @param   p_limit_check_current            Pointer to current Value for a
     * given limit_check_id.
     * @return  None; instead check class Field "ErrState"         
     * @return  VL53L0X_ERROR_INVALID_PARAMS   This error is returned when
     * limit_check_id value is out of range.
     */
    void Get_limit_check_current( uint16_t limit_check_id, 
                                  TFP1616 *p_limit_check_current);

    /**
     * @brief  Return a the Status of the specified check limit
     *
     * @par Function Description
     * This function returns the Status of the specified check limit.
     * The value indicate if the check is fail or not.
     * The limit check is identified with the limit_check_id.
     *
     * @note This function doesn't Access to the device
     * 
     * @param   limit_check_id                  Limit Check ID
     (0<= limit_check_id < VL53L0X_GetNumberOfLimitCheck() ).
     * @param   p_limit_check_status             Pointer to the
     Limit Check Status of the given check limit.
     * LimitCheckStatus :
     * 0 the check is not fail
     * 1 the check if fail or not enabled
     *
     * @return  None; instead check class Field "ErrState"         
     * @return  VL53L0X_ERROR_INVALID_PARAMS   This error is
     returned when limit_check_id value is out of range.             
     */
    void Get_limit_check_status(uint16_t limit_check_id, uint8_t *p_limit_check_status);

    /**
     * Get continuous mode Inter-Measurement period in milliseconds
     *
     * @par Function Description
     * When trying to set too short time return  INVALID_PARAMS minimal value
     *
     * @note This function Access to the device
     * 
     * @param   p_measure_period_ms  Pointer to programmed
     *  Inter-Measurement Period in milliseconds.
     * @return  None; instead check class Field "ErrState"                               
     */
    void Get_measure_period_ms(uint32_t *p_measure_period_ms);

    /**
     * Program continuous mode Inter-Measurement period in milliseconds
     *
     * @par Function Description
     * When trying to set too short time return  INVALID_PARAMS minimal value
     *
     * @note This function Access to the device
     * 
     * @param   measure_period_ms   Inter-Measurement Period in ms.
     * @return  None; instead check class Field "ErrState"                         
     */
    void Set_measure_period_ms( uint32_t measure_period_ms );

    /**
     * @brief Do an hard reset or soft reset (depending on implementation) of the
     * device \nAfter call of this function, device must be in same state as right
     * after a power-up sequence.This function will change the VL53L0X_State to
     * VL53L0X_STATE_POWERDOWN.
     *
     * @note This function Access to the device
     * 
     * @return  None; instead check class Field "ErrState" 
     */
    void Reset_device();

    /**
     * @brief  Get setup of Wrap around Check
     *
     * @par Function Description
     * This function get the wrapAround check enable parameters
     *
     * @note This function Access to the device
     * 
     * @return  uint8_t  Wrap around Check state 0=disabled or 1 = enabled
     * @return  None  	   Also check class Field "ErrState"   
     */
    uint8_t Get_Wrap_Around_Chk_En();

    /**
     * @brief  Enable (or disable) Wrap around Check
     *
     * @note This function Access to the device
     *
     * 
     * @param   wrap_around_Chk_En  Wrap around Check to be set
     *                                 0=disabled, other = enabled
     * @return  None; instead check class Field "ErrState"  
     */
    void Set_wrap_around_Chk_En( uint8_t wrap_around_Chk_En);

    /**
     * @brief Sets the VCSEL pulse period.
     *
     * @par Function Description
     * This function retrieves the VCSEL pulse period for the given period type.
     *
     * @note This function Accesses the device
     * 
     * @param   Vcsel_Range_Phase	      VCSEL period identifier (pre-range|final).
     * @param   vcsel_PPeriod          VCSEL period value
     * @return  None; instead check class Field "ErrState"        
     * @return  VL53L0X_ERROR_INVALID_PARAMS  Error VcselPeriodType parameter not
     *                                       supported.
     */
    void Set_vcsel_PPeriod( VL53L0X_Range_Phase Vcsel_Range_Phase, 
                                uint8_t vcsel_PPeriod);

    /**
     * @brief Set low and high Interrupt thresholds for a given mode
     * (ranging, ALS, ...) for a given device
     *
     * @par Function Description
     * Set low and high Interrupt thresholds for a given mode (ranging, ALS, ...)
     * for a given device
     *
     * @note This function Access to the device
     *
     * @note DeviceMode is ignored for the current device
     * 
     * @param   device_mode       Device Mode for which change thresholds
     * @param   threshold_low     Low threshold (mm, lux ..., depending on the mode)
     * @param   threshold_high    High threshold (mm, lux ..., depending on the mode)
     * @return  None; instead check class Field "ErrState"
     */
    void Set_interrupt_thresholds( VL53L0X_DeviceModes device_mode, 
           TFP1616 threshold_low,  TFP1616 threshold_high);

    /**
     * @brief  Get high and low Interrupt thresholds for a given mode
     *  (ranging, ALS, ...) for a given device
     *
     * @par Function Description
     * Get high and low Interrupt thresholds for a given mode (ranging, ALS, ...)
     * for a given device
     *
     * @note This function Access to the device
     *
     * @note DeviceMode is ignored for the current device
     * 
     * @param   device_mode       Device Mode from which read thresholds
     * @param   p_threshold_low    Low threshold (mm, lux ..., depending on the mode)
     * @param   p_threshold_high   High threshold (mm, lux ..., depending on the mode)
     * @return  None; instead check class Field "ErrState"
     */
    void Get_interrupt_thresholds( VL53L0X_DeviceModes device_mode, 
    		TFP1616 *p_threshold_low, TFP1616 *p_threshold_high);

    /**
     * @brief Gets the (on/off) state of all sequence steps.
     *
     * @par Function Description
     * This function retrieves the state of all sequence step in the scheduler.
     *
     * @note This function Accesses the device
     * 
     * @return  VL53L0X_Sequence_Steps_t      Struct containing result.
     *                                          Also check class Field "ErrState"        
     */
    VL53L0X_Sequence_Steps_t Get_sequence_step_enables();

    /**
     * @brief Sets the (on/off) state of a requested sequence step.
     *
     * @par Function Description
     * This function enables/disables a requested sequence step.
     *
     * @note This function Accesses the device
     * 
     * @param   sequence_step_id	         Sequence step identifier.
     * @param   sequence_step_enabled          Demanded state {0=Off,1=On}
     *                                       is enabled.
     * @return  None; instead check class Field "ErrState"        
     * @return  VL53L0X_ERROR_INVALID_PARAMS  Error SequenceStepId parameter not
     *                                       supported.   
     */
    void Set_sequence_step_enable(VL53L0X_SequenceStepId sequence_step_id, 
                                  uint8_t sequence_step_enabled);

    /**
     * @brief  Gets the fraction enable parameter indicating the resolution of
     * range measurements.
     *
     * @par Function Description
     * Gets the fraction enable state, which translates to the resolution of
     * range measurements as follows :Enabled:=0.25mm resolution,
     * Not Enabled:=1mm resolution.
     *
     * @note This function Accesses the device
     * 
     * @param   p_enabled           Output Parameter reporting the fraction enable state.
     *
     * @return  None; instead check class Field "ErrState"                         
     */
    void Get_fraction_enable( uint8_t *p_enabled);

    /**
     * @brief  Sets the resolution of range measurements.
     * @par Function Description
     * Set resolution of range measurements to either 0.25mm if
     * fraction enabled or 1mm if not enabled.
     *
     * @note This function Accesses the device
     * 
     * @param   enable            Enable high resolution
     *
     * @return  None; instead check class Field "ErrState"              
     */
    void Set_range_fraction_enable(  uint8_t enable);

    /**
    * @brief Return the VL53L0X Device Implementation Version
    *
    * @note This function doesn't access to the device
    *
    * @param   p_version              Pointer to current Device Implementation Version
    * @return  None; instead check class Field "ErrState" 
    */
    void Get_version(VL53L0X_Version_t *p_version);

    /**
     * @brief Reads the Product Revision for a for given Device
     * This function can be used to distinguish cut1.0 from cut1.1.
     *
     * @note This function Access to the device
     * 
     * @param   p_product_revision_major  Pointer to Product Revision Major
     * for a given Device
     * @param   p_product_revision_minor  Pointer to Product Revision Minor
     * for a given Device
     * @return  None; instead check class Field "ErrState"  
     */
    void Get_product_revision(  uint8_t *p_product_revision_major, 
            uint8_t *p_product_revision_minor);

    /**
     * @brief  Retrieve current device parameters
     * @par Function Description
     * Get actual parameters of the device
     * @li Then start ranging operation.
     *
     * @note This function Access to the device
     * 
     * @return   VL53L0X_DeviceParams_t     Current device parameters.
     * 					    Also check class Field "ErrState" 
     */
    VL53L0X_DeviceParams_t Get_device_parameters();

    /**
     * @brief Return the Device Specification Version used for the current
     * implementation.
     *
     * @note This function doesn't access to the device
     *
     * @param   p_Device_spec_version       Pointer to current Device Specification Version
     * @return  None; instead check class Field "ErrState"    
     */
    void Get_Device_spec_version(VL53L0X_Version_t  *p_Device_spec_version);

    /**
     * @brief Reads the internal state of the Device for a given Device
     *
     * @note This function doesn't access to the device
     * 
     * @param   p_Device_state             Pointer to current state of the Device for a
     * given Device
     * @return  None; instead check class Field "ErrState" 
     */
    void Get_Device_state(VL53L0X_State *p_Device_state);

	/* New Strategy, Moving to a global variable to track error states: */
	VL53L0X_Error  ErrState;
	
    VL53L0X_State Current_State;  /*!< Current state of this device; use Set_Current_State to change it  */

    /*** End High level API ***/
private:
    void Wait_read_strobe();

    void Check_and_load_interrupt_settings( uint8_t start_not_stopflag);

    /* api_core.h functions */
    void Get_info_from_device( uint8_t option);

    uint32_t Decode_timeout(uint16_t encoded_timeout);

    uint32_t Calc_timeout_us(uint16_t timeout_period_mclks,
                                     uint8_t vcsel_period_pclks);

    void Poll_Measure_Completion(); // was Measurement_poll_for_completion

    void Load_tuning_settings( uint8_t *p_tuning_setting_buffer );

    void Get_Device_range_status( uint8_t device_range_status,
            TFP1616 signal_rate, uint16_t effective_SPAD_rtn_count,
            TRangeResults *p_ranging_results,
            uint8_t *p_Device_range_status);

    void Calc_sigma_estimate(
            TRangeResults *p_ranging_results,
            TFP1616 *p_sigma_estimate, uint32_t *p_dmax_mm);
            
    uint32_t Calc_timeout_mclks(uint32_t timeout_period_us,
                                        uint8_t vcsel_period_pclks);
    
    void Calc_dmax( TFP1616 total_SIG_rate_mcps,
        TFP1616 total_corr_SIG_rate_mcps,
        TFP1616 pw_mult, uint32_t sigma_estimate_p1,
        TFP1616 sigma_estimate_p2,  uint32_t peak_vcsel_duration_us,
        uint32_t *pd_max_mm);
        
    uint16_t Encode_timeout(uint32_t timeout_macro_clks);

    /* api_calibration.h functions */
    void VL53L0X_Apply_Offset_Cal();
    
    void Perf_vhv_calibration( uint8_t *p_vhv_settings, 
            const uint8_t get_data_enable,  const uint8_t restore_config);
            
    void Perf_single_Ref_calibration( uint8_t vhv_init_byte );
    
    void Ref_calibration_io( uint8_t read_not_write,
            uint8_t vhv_settings, uint8_t phase_cal,
            uint8_t *p_vhv_settings, uint8_t *p_phase_cal,
            const uint8_t vhv_enable, const uint8_t phase_enable);
            
    void Perf_phase_calibration( uint8_t *p_phase_cal, const uint8_t get_data_enable,
            const uint8_t restore_config);
            
    void Enable_Ref_SPADS(uint8_t aperture_SPADS, uint8_t good_SPAD_array[],
            uint8_t SPAD_array[], uint32_t size, uint32_t start,
            uint32_t offset, uint32_t SPAD_count,  uint32_t *p_last_SPAD);
                                   
    void Get_Next_Good_SPAD(uint8_t good_SPAD_array[], uint32_t size,
                            uint32_t curr, int32_t *p_next);
                            
    void Enable_SPAD_bit( uint8_t SPAD_array[], uint32_t size, uint32_t SPAD_index);
                                    
    void Get_Ref_SPAD_map( uint8_t *p_Ref_SPAD_array );
    
    uint16_t Get_Perf_Ref_SIG_measurement();
    

    /* Read function of the ID device */
    virtual int read_id(uint8_t *id);
    
    void Wait_Measurement_Ready();

    void Wait_Stop_Completed();

    /**
     * @brief execute delay in all polling API call
     *
     * A typical multi-thread or RTOs implementation is to sleep the task for some 
     * 5ms (with 100Hz max rate faster polling is not needed)
     * if nothing specific is need you can define it as an empty/void macro
     * @code
     * #define VL53L0X_PollingDelay(...) (void)0
     * @endcode
     * 
     * @return  None; instead check class Field "ErrState"    
     */
    void Polling_delay();   /* usually best implemented as a real function */

    ///////////////////////////////////////////////////////////////////////////////////////////////////////
    //Added functions                                                                                    //
    ///////////////////////////////////////////////////////////////////////////////////////////////////////

    /**
     * @brief  Cycle Power to Device
     *
     * @return ErrState - ErrState 0 = ok, 1 = error
     */
    int32_t Cycle_power(void);

    void count_enabled_SPADS(uint8_t SPAD_array[],  uint32_t byte_count, 
       uint32_t max_SPADS, uint32_t *p_total_SPADS_enabled, uint8_t *p_is_aperture);

        /**
     * @brief Gets the name of a given sequence step.
     *
     * @par Function Description
     * This function retrieves the name of sequence steps corresponding to
     * SequenceStepId.
     *
     * @note This function doesn't Accesses the device
     *
     * @param   sequence_step_id               Sequence step identifier.
     * @param   p_sequence_steps_string         Pointer to Info string
     *
     * @return  None; instead check class Field "ErrState"        
     */
    void Get_sequence_steps_info(VL53L0X_SequenceStepId sequence_step_id,
            char *p_sequence_steps_string);

    /**
    * @brief Get the frequency of the timer used for ranging results time stamps
    *
    * @param[out] p_timer_freq_hz : pointer for timer frequency
    *
    * @return ErrState : 0 = ok, 1 = error
    */
    int32_t Get_timer_frequency(int32_t *p_timer_freq_hz);

    /**
    * @brief Get the timer value in units of timer_freq_hz (see Get_timestamp_frequency())
    *
    * @param[out] p_timer_count : pointer for timer count value
    *
    * @return ErrState : 0 = ok, 1 = error
    */
    int32_t Get_timer_value(int32_t *p_timer_count);

    /**
    * @brief Configure ranging interrupt reported to system
    *
    * @note This function is not Implemented
    * 
    * @param   interrupt_mask         Mask of interrupt to Enable/disable
    *  (0:interrupt disabled or 1: interrupt enabled)
    * @return  VL53L0X_ERROR_NOT_IMPLEMENTED   Not implemented
    */
    void Enable_interrupt_mask(uint32_t interrupt_mask);

    /**
     * @brief  Get Dmax Calibration Parameters for a given device
     *
     * @note This function Access to the device
     * 
     * @param   p_range_milli_meter        Pointer to Calibration Distance
     * @param   p_SIG_rate_rtn_MHz   Pointer to Signal rate return
     * @return  None; instead check class Field "ErrState"   
     */
    void Get_dmax_cal_parameters(uint16_t *p_range_milli_meter,
             TFP1616 *p_SIG_rate_rtn_MHz);

    /**
    * @brief   Set Dmax Calibration Parameters for a given device
    * When one of the parameter is zero, this function will get parameter
    * from NVM.
    * @note This function doesn't Access to the device
    * 
    * @param   range_milli_meter        Calibration Distance
    * @param   signal_rate_rtn_MHz   Signal rate return read at CalDistance
    * @return  None; instead check class Field "ErrState"  
     
    */
    void Get_dmax_cal_parameters(uint16_t range_milli_meter, 
            TFP1616 signal_rate_rtn_MHz);

    /**
    * @brief Retrieve the measurements from device for a given setup
    *
    * @par Function Description
    * Get data from last successful Histogram measurement
    * @warning USER should take care about  @a VL53L0X_GetNumberOfROIZones()
    * before get data.
    * Device will fill a NumberOfROIZones times the corresponding data structure
    * used in the measurement function.
    *
    * @note This function is not Implemented
    * 
    * @param   p_histogram_measurement_data   Pointer to the histogram data structure.
    * @return  VL53L0X_ERROR_NOT_IMPLEMENTED   Not implemented
    */
    void Get_histogram_measurement_data(
            VL53L0X_HistogramMeasurementData_t *p_histogram_measurement_data);

    /**
    * @brief  Get current new device mode
    * @par Function Description
    * Get current Histogram mode of a Device
    *
    * @note This function doesn't Access to the device
    * 
    * @param   p_histogram_mode        Pointer to current Histogram Mode value
    *                                Valid values are:
    *                                VL53L0X_HISTOGRAMMODE_DISABLED
    *                                VL53L0X_DEVICEMODE_SINGLE_HISTOGRAM
    *                                VL53L0X_HISTOGRAMMODE_REFERENCE_ONLY
    *                                VL53L0X_HISTOGRAMMODE_RETURN_ONLY
    *                                VL53L0X_HISTOGRAMMODE_BOTH
    * @return  None; instead check class Field "ErrState" 
    */
    void Get_histogram_mode(
            VL53L0X_HistogramModes *p_histogram_mode);

    /**
     * @brief  Set a new Histogram mode
     * @par Function Description
     * Set device to a new Histogram mode
     *
     * @note This function doesn't Access to the device
     * 
     * @param   histogram_mode         New device mode to apply
     *                                Valid values are:
     *                                VL53L0X_HISTOGRAMMODE_DISABLED
     *                                VL53L0X_DEVICEMODE_SINGLE_HISTOGRAM
     *                                VL53L0X_HISTOGRAMMODE_REFERENCE_ONLY
     *                                VL53L0X_HISTOGRAMMODE_RETURN_ONLY
     *                                VL53L0X_HISTOGRAMMODE_BOTH
     *
     * @return  None; instead check class Field "ErrState"               
     * @return  VL53L0X_ERROR_MODE_NOT_SUPPORTED     This error occurs when
     * HistogramMode is not in the supported list
     */
    void Set_histogram_mode(
            VL53L0X_HistogramModes histogram_mode);

    /**
     * @brief Get the linearity corrective gain
     *
     * @par Function Description
     * Should only be used after a successful call to @a VL53L0X_DataInit to backup
     * device NVM value
     *
     * @note This function Access to the device
     * 
     * @param   p_linearity_corrective_gain           Pointer to the linearity
     * corrective gain in x1000
     * if value is 1000 then no modification is applied.
     * @return  None; instead check class Field "ErrState"    
     */
    void Get_linearity_corrective_gain(
            uint16_t *p_linearity_corrective_gain);

    /**
     * Set the linearity corrective gain
     *
     * @note This function Access to the device
     * 
     * @param   linearity_corrective_gain            Linearity corrective
     * gain in x1000
     * if value is 1000 then no modification is applied.
     * @return  None; instead check class Field "ErrState"    
     */
    void Set_linearity_corrective_gain(
            int16_t linearity_corrective_gain);

    /**
     * @brief Get the Maximum number of ROI Zones managed by the Device
     *
     * @par Function Description
     * Get Maximum number of ROI Zones managed by the Device.
     *
     * @note This function doesn't Access to the device
     * 
     * @param   p_max_number_of_roi_zones   Pointer to the Maximum Number
     *  of ROI Zones value.
     * @return  None; instead check class Field "ErrState"  
     */
    void Get_max_number_of_roi_zones(
            uint8_t *p_max_number_of_roi_zones);

    /**
     * @brief Retrieve the Reference Signal after a measurements
     *
     * @par Function Description
     * Get Reference Signal from last successful Ranging measurement
     * This function return a valid value after that you call the
     * @a VL53L0X_GetRangingMeasurementData().
     *
     * @note This function Access to the device
     * 
     * @param   p_measurement_Ref_signal    Pointer to the Ref Signal to fill up.
     * @return  None; instead check class Field "ErrState" 
     */
    void Get_Measurement_Ref_signal(
            TFP1616 *p_measurement_Ref_signal);

    /**
     * @brief  Get the number of the check limit managed by a given Device
     *
     * @par Function Description
     * This function give the number of the check limit managed by the Device
     *
     * @note This function doesn't Access to the device
     *
     * @param   p_number_of_limit_check           Pointer to the number of check limit.
     * @return  None; instead check class Field "ErrState" 
     */
    void Get_number_of_limit_check(
                       uint16_t *p_number_of_limit_check);

    /**
     * @brief Get the number of ROI Zones managed by the Device
     *
     * @par Function Description
     * Get number of ROI Zones managed by the Device
     * USER should take care about  @a VL53L0X_GetNumberOfROIZones()
     * before get data after a perform measurement.
     * Device will fill a NumberOfROIZones times the corresponding data
     * structure used in the measurement function.
     *
     * @note This function doesn't Access to the device
     *
     * 
     * @param   p_number_of_roi_zones     Pointer to the Number of ROI Zones value.
     * @return  None; instead check class Field "ErrState" 
     */
    void Get_number_of_roi_zones(
            uint8_t *p_number_of_roi_zones);

    /**
     * @brief Set the number of ROI Zones to be used for a specific Device
     *
     * @par Function Description
     * Set the number of ROI Zones to be used for a specific Device.
     * The programmed value should be less than the max number of ROI Zones given
     * with @a VL53L0X_GetMaxNumberOfROIZones().
     * This version of API manages only one zone.
     * 
     * @param   number_of_roi_zones      Number of ROI Zones to be used 
     * @return  None; instead check class Field "ErrState"         
     * @return  VL53L0X_ERROR_INVALID_PARAMS   This error is returned if NumberOfROIZones != 1
     */
    void Set_number_of_roi_zones(  uint8_t number_of_roi_zones);

    /**
     * @brief Gets number of sequence steps managed by the API.
     *
     * @par Function Description
     * This function retrieves the number of sequence steps currently managed
     * by the API
     *
     * @note This function Accesses the device
     * 
     * @param   p_number_of_sequence_steps       Out parameter reporting the number of
     *                                       sequence steps.
     * @return  None; instead check class Field "ErrState"        
     */
    void Get_number_of_sequence_steps( uint8_t *p_number_of_sequence_steps);
    /**
     * @brief Get the power mode for a given Device
     *
     * @note This function Access to the device
     * 
     * @param   p_power_mode            Pointer to the current value of the power
     * mode. see ::VL53L0X_PowerModes
     *                                Valid values are:
     *                                VL53L0X_POWERMODE_STANDBY_LEVEL1,
     *                                VL53L0X_POWERMODE_IDLE_LEVEL1
     * @return  None; instead check class Field "ErrState"
     */
    void Get_power_mode( VL53L0X_PowerModes *p_power_mode);

    /**
     * @brief Set the power mode for a given Device
     * The power mode can be Standby or Idle. Different level of both Standby and
     * Idle can exists.
     * This function should not be used when device is in Ranging state.
     *
     * @note This function Access to the device
     * 
     * @param   power_mode             The value of the power mode to set.
     * see ::VL53L0X_PowerModes
     *                                Valid values are:
     *                                VL53L0X_POWERMODE_STANDBY_LEVEL1,
     *                                VL53L0X_POWERMODE_IDLE_LEVEL1
     * @return  None; instead check class Field "ErrState"              
     * @return  VL53L0X_ERROR_MODE_NOT_SUPPORTED    This error occurs when PowerMode
     * is not in the supported list
     */
    void Set_power_mode(VL53L0X_PowerModes power_mode);

    /**
     * @brief Retrieves SPAD configuration
     *
     * @par Function Description
     * This function retrieves the current number of applied reference SPADS
     * and also their type : Aperture or Non-Aperture.
     *
     * @note This function Access to the device
     * 
     * @param   p_SPAD_count                 Number ref SPAD Count
     * @param   p_is_aperture_SPADS              Reports if SPADS are of type
     *                                       aperture or non-aperture.
     *                                       1:=aperture, 0:=Non-Aperture
     * @return  None; instead check class Field "ErrState"        
     * @return  VL53L0X_ERROR_REF_SPAD_INIT   Error in the in the reference
     *                                       SPAD configuration.
     */
    void wrapped_Get_Reference_SPADS(
            uint32_t *p_SPAD_count, uint8_t *p_is_aperture_SPADS);

    /**
     * @brief Gets the (on/off) state of a requested sequence step.
     *
     * @par Function Description
     * This function retrieves the state of a requested sequence step, i.e. on/off.
     *
     * @note This function Accesses the device
     *
     * @param   sequence_step_id         Sequence step identifier.
     * @param   p_sequence_step_enabled   Out parameter reporting if the sequence step
     *                                 is enabled {0=Off,1=On}.
     * @return  None; instead check class Field "ErrState"        
     * @return  VL53L0X_ERROR_INVALID_PARAMS  Error SequenceStepId parameter not
     *                                        supported.
     */
    void Get_sequence_step_enable(
            VL53L0X_SequenceStepId sequence_step_id, uint8_t *p_sequence_step_enabled);


    /**
     * @brief Gets the timeout of a requested sequence step.
     *
     * @par Function Description
     * This function retrieves the timeout of a requested sequence step.
     *
     * @note This function Accesses the device
     *
     * @param   sequence_step_id               Sequence step identifier.
     * @param   p_time_out_milli_secs            Timeout value.
     * @return  None; instead check class Field "ErrState"        
     * @return  VL53L0X_ERROR_INVALID_PARAMS  Error SequenceStepId parameter not
     *                                       supported.
     */
    void Get_Sequence_Step_Timeout(VL53L0X_SequenceStepId sequence_step_id,
                                            uint32_t *p_time_out_micro_secs);

    /**
     * @brief Sets the timeout of a requested sequence step.
     *
     * @par Function Description
     * This function sets the timeout of a requested sequence step.
     *
     * @note This function Accesses the device
     * 
     * @param   sequence_step_id               Sequence step identifier.
     * @param   time_out_milli_secs             Demanded timeout
     * @return  None; instead check class Field "ErrState"        
     * @return  VL53L0X_ERROR_INVALID_PARAMS  Error SequenceStepId parameter not
     *                                       supported.
     */
    void Set_Sequence_Step_Timeout(VL53L0X_SequenceStepId sequence_step_id,
                                            uint32_t timeout_micro_secs);

    /**
    * @brief  Get the current SPAD Ambient Damper Factor value
    *
    * @par Function Description
    * This function get the SPAD Ambient Damper Factor value
    *
    * @note This function Access to the device
    * 
    * @param   p_SPAD_ambient_damper_factor      Pointer to programmed SPAD Ambient
    * Damper Factor value
    * @return  None; instead check class Field "ErrState"         
    */
    void Get_SPAD_ambient_damper_factor(
            uint16_t *p_SPAD_ambient_damper_factor);
    /**
    * @brief  Set the SPAD Ambient Damper Factor value
    *
    * @par Function Description
    * This function set the SPAD Ambient Damper Factor value
    *
    * @note This function Access to the device
    * 
    * @param   SPAD_ambient_damper_factor       SPAD Ambient Damper Factor value
    * @return  None; instead check class Field "ErrState"         
    */
    void Set_SPAD_ambient_damper_factor(
            uint16_t SPAD_ambient_damper_factor);

    /**
     * @brief  Get the current SPAD Ambient Damper Threshold value
     *
     * @par Function Description
     * This function get the SPAD Ambient Damper Threshold value
     *
     * @note This function Access to the device
     * 
     * @param   p_SPAD_ambient_damper_threshold   Pointer to programmed
     *                                        SPAD Ambient Damper Threshold value
     * @return  None; instead check class Field "ErrState"         
     */
    void Get_SPAD_ambient_damper_threshold(
            uint16_t *p_SPAD_ambient_damper_threshold);

    /**
     * @brief  Set the SPAD Ambient Damper Threshold value
     *
     * @par Function Description
     * This function set the SPAD Ambient Damper Threshold value
     *
     * @note This function Access to the device
     * 
     * @param   SPAD_ambient_damper_threshold    SPAD Ambient Damper Threshold value
     * @return  None; instead check class Field "ErrState"         
     */
    void Set_SPAD_ambient_damper_threshold(
            uint16_t SPAD_ambient_damper_threshold);

    /**
     * @brief Get the maximal distance for actual setup
     * @par Function Description
     * Device must be initialized through @a VL53L0X_SetParameters() prior calling
     * this function.
     *
     * Any range value more than the value returned is to be considered as
     * "no target detected" or
     * "no target in detectable range"\n
     * @warning The maximal distance depends on the setup
     *
     * @note This function is not Implemented
     * 
     * @param   p_upper_limit_milli_meter   The maximal range limit for actual setup
     * (in millimeter)
     * @return  VL53L0X_ERROR_NOT_IMPLEMENTED        Not implemented
     */
    void Get_upper_limit_milli_meter(
            uint16_t *p_upper_limit_milli_meter);

    /**
    * @brief Get the tuning settings pointer and the internal external switch
    * value.
    *
    * This function is used to get the Tuning settings buffer pointer and the
    * value.
    * of the switch to select either external or internal tuning settings.
    *
    * @note This function Access to the device
    * 
    * @param   pp_tuning_setting_buffer      Pointer to tuning settings buffer.
    * @param   p_use_internal_tuning_settings Pointer to store Use internal tuning
    *                                     settings value.
    * @return  None; instead check class Field "ErrState"      
    */
    void Get_tuning_setting_buffer( uint8_t **pp_tuning_setting_buffer, 
                  uint8_t *p_use_internal_tuning_settings);

    /**
     * @brief Set the tuning settings pointer
     *
     * This function is used to specify the Tuning settings buffer to be used
     * for a given device. The buffer contains all the necessary data to permit
     * the API to write tuning settings.
     * This function permit to force the usage of either external or internal
     * tuning settings.
     *
     * @note This function Access to the device
     * 
     * @param   p_tuning_setting_buffer            Pointer to tuning settings buffer.
     * @param   use_internal_tuning_settings       Use internal tuning settings value.
     * @return  None; instead check class Field "ErrState" 
     */
    void Set_tuning_setting_buffer(  uint8_t *p_tuning_setting_buffer, 
            uint8_t use_internal_tuning_settings);

    /**
     * @defgroup VL53L0X_registerAccess_group Device Register Access Functions
     * @brief    Device Register Access Functions
     *  @{
     */

    /**
     * Lock comms interface to serialize all commands to a shared I2C interface for a specific device
     * 
     * @return  None; instead check class Field "ErrState"    
     */
    void VL53L0X_lock_sequence_access();

    /**
     * Unlock comms interface to serialize all commands to a shared I2C interface for a specific device
     * 
     * @return  None; instead check class Field "ErrState"    
     */
    void VL53L0X_unlock_sequence_access();

    /**
     * @brief  Prepare device for operation
     * @par Function Description
     * Update device with provided parameters
     * @li Then start ranging operation.
     *
     * @note This function Access to the device
     * 
     * @param   pDeviceParameters     Pointer to store current device parameters.
     * @return  None; instead check class Field "ErrState" 
     */
    void VL53L0x_set_device_parameters(
            const VL53L0X_DeviceParams_t *pDeviceParameters);

    /**
     * Set Group parameter Hold state
     *
     * @par Function Description
     * Set or remove device internal group parameter hold
     *
     * @note This function is not Implemented
     * 
     * @param   group_param_hold   Group parameter Hold state to be set (on/off)
     * @return  VL53L0X_ERROR_NOT_IMPLEMENTED        Not implemented
     */
    void Set_group_param_hold(uint8_t group_param_hold);

    /**
     * @brief Wait for device ready for a new measurement command.
     * Blocking function.
     *
     * @note This function is not Implemented
     * 
     * @param   max_loop    Max Number of polling loop (timeout).
     * @return  VL53L0X_ERROR_NOT_IMPLEMENTED   Not implemented
     */
    void Wait_device_ready_for_new_measurement( uint32_t max_loop);

private:
/******************************************************************************/
/****************** Write and read functions from I2C *************************/
/******************************************************************************/
    /**
     * Thread safe Update (read/modify/write) single byte register
     *
     * Final_reg = (Initial_reg & and_mask) | or_mask
     *
     * 
     * @param   index      The register index
     * @param   and_mask    8 bit and data
     * @param   or_mask     8 bit or data
     * @return  None; instead check class Field "ErrState"    
     */
    void Register_BitMask(uint8_t index, uint8_t and_mask, uint8_t or_mask);

    /* Write and read functions from I2C */
    /**
     * Write single byte register
     * 
     * @param   index     The register index
     * @param   data      8 bit register data
     * @return  None; instead check class Field "ErrState"    
     */
    void Write_Byte( uint8_t index, uint8_t data);

    /**
     * Write word register
     * 
     * @param   index     The register index
     * @param   data      16 bit register data
     * @return  None; instead check class Field "ErrState"    
     */
    void Write_Word( uint8_t index, uint16_t data);
    /**
     * Write double word (4 byte) register
     * 
     * @param   index     The register index
     * @param   data      32 bit register data
     * @return  None; instead check class Field "ErrState"    
     */
    void Write_DWord( uint8_t index, uint32_t data);

    /**
     * Read single byte register
     * 
     * @param   index     The register index
     * @return  uint8_t  Returned 8 bit data; also check class Field "ErrState"    
     */
	uint8_t Read_Byte(uint8_t index);
	
    /**
     * Read word (2byte) register
     * 
     * @param   index     The register index
     * @return  uint16_t  Returned 16 bit data; also check class Field "ErrState"    
     */
    uint16_t Read_Word( uint8_t index);
    /**
     * Read dword (4byte) register
     * 
     * @param   index     The register index
     * @return  uint32_t  Returned 32 bit data; also check class Field "ErrState"    
     */
    uint32_t Read_DWord( uint8_t index);
    
    /**
     * @brief  Writes a buffer towards the I2C peripheral device.
     * 
	 * @param  RegisterAddr specifies the internal address register
	 * @param  p_data pointer to the byte-array data to send
	 *         where to start writing to (must be correctly masked).
	 * @param  NumByteToWrite number of bytes to be written.
	 * @retval VL53L0X_OK  if  ok,
	 * @retval VL53L0X_ERROR_CONTROL_INTERFACE  if  an  I2C error has occured, or
	 * @retval VL53L0X_ERROR_I2C_BUF_OVERFLOW on temporary buffer overflow (i.e. NumByteToWrite was too high)
	 * @note   On some devices if NumByteToWrite is greater
	 *         than one, the RegisterAddr must be masked correctly!
     */
    void I2c_Write(uint8_t RegisterAddr, uint8_t *p_data, uint16_t NumByteToWrite);

    /**
     * @brief  Reads a buffer from the I2C peripheral device.
     * 
	 * @param  RegisterAddr specifies the internal address register
	 * @param  p_data pointer to the byte-array data to receive
	 *         where to start writing to (must be correctly masked).
	 * @param  NumByteToRead number of bytes to be read; maximum VL53L0X_MAX_I2C_XFER_SIZE
     * @retval 0 if ok,
     * @retval -1 if an I2C error has occured
     * @note   On some devices if NumByteToRead is greater
     *         than one, the RegisterAddr must be masked correctly!
     */
    void I2c_Read(uint8_t RegisterAddr, uint8_t *p_data, uint16_t NumByteToRead);

    /* IO Device */
    I2C *_dev_i2c;

    /*!< i2c device address user specific field */
    uint8_t   I2cDevAddr;     

private:
    uint8_t Is_ApertureSPAD(uint32_t SPAD_index);
    
    void Reverse_bytes(uint8_t *data, uint32_t size);

    void Range_meas_int_continuous_mode(void (*fptr)(void));

    uint32_t ISQRT(uint32_t num);

    uint32_t Quadrature_sum(uint32_t a, uint32_t b);
    
    void Set_Current_State( VL53L0X_State NewState )
    {  if (ErrState == VL53L0X_OK) { Current_State = NewState; }
    	  else { Current_State = VL53L0X_STATE_ERROR; }
	} // end of Set_Current_State
	
	// NB: it seems that the state SequenceConfig is only written to never read from ;)
    void Set_SequenceConfig ( uint8_t NewSequenceConfig ) 
    { Write_Byte(REG_SYSTEM_SEQUENCE_CONFIG, NewSequenceConfig);
      if (ErrState == VL53L0X_OK) { SequenceConfig = NewSequenceConfig; } } 

private:
    static const unsigned int TEMP_BUF_SIZE = 64;

    /* Digital out pin */
    DigitalOut *_gpio0;
    
    /* Measure detection IRQ */
    InterruptIn *_gpio1Int;
    
	/**
	 * @brief was VL53L0X_Dev_t, Generic device information
	 *
	 * merged with VL53L0X_DevData_t that embeds ST FlightSense devdata
	 * VL53L0X Device device ST private data structure \n
	 * End user should never access any of these field directly \n
	 */
    VL53L0X_DMaxData_t DMaxData;
    /*!< Dmax Data */
    int32_t	 Last_Offset_Cal_um;
    /*!< backed up Offset_Cal value found last time, but never used !!!*/
    int32_t	 NVM_Offset_Cal_um;
    /*!< backed up NVM value representing additional offset adjustment */
    VL53L0X_DeviceParams_t CurrParams;
    /*!< Current Device Parameter */
    TRangeResults LastRangeMeasure;
    /*!< Ranging Data */
    VL53L0X_HistogramMeasurementData_t LastHistogramMeasure;
    /*!< Histogram Data */
    VL53L0X_DeviceSpecificParameters_t DevSpecParams;
    /*!< Parameters specific to the device */
    VL53L0X_SPADData_t SPADData;
    /*!< SPAD Data */
    uint8_t SequenceConfig;
    /*!< Internal value for the sequence config */
    uint8_t RangeFractionalEnable;
    /*!< Enable/Disable fractional part of ranging data */
    VL53L0X_PowerModes PowerMode;
    /*!< Current Power Mode	 */
    uint16_t SigmaEstRefArray;
    /*!< Reference array sigma value in 1/100th of [mm] e.g. 100 = 1mm */
    uint16_t SigmaEstEffPulseWidth;
    /*!< Effective Pulse width for sigma estimate in 1/100th of ns e.g. 900 = 9.0ns */
    uint16_t SigmaEstEffAmbWidth;
    /*!< Effective Ambient width for sigma estimate in 1/100th of ns
    * e.g. 500 = 5.0ns */
    uint8_t StopVariable;
    /*!< StopVariable used during the stop sequence */
    uint16_t targetRefRate;
    /*!< Target Ambient Rate for Ref SPAD management */
    TFP1616 SigmaEstimate;
    /*!< Sigma Estimate - based on ambient & VCSEL rates and signal_total_events */
    TFP1616 SignalEstimate;
    /*!< Signal Estimate - based on ambient & VCSEL rates and cross talk */
    TFP1616 LastSignalRefMcps;
    /*!< Latest Signal ref in Mcps */
    uint8_t *pTuningSettingsPointer;
    /*!< Pointer for Tuning Settings table */
    uint8_t UseInternalTuningSettings;
    /*!< Indicate if we use	 Tuning Settings table */
    uint16_t LinearityCorrectiveGain;
    /*!< Linearity Corrective Gain value in x1000 */
    uint16_t DmaxCalRangeMilliMeter;
    /*!< Dmax Calibration Range millimeter */
    TFP1616 DmaxCalSignalRateRtnMHz;
    /*!< Dmax Calibration Signal Rate Return MHz */    
};

#endif /* _VL53L0X_CLASS_H_ */