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LightRanger 8 click

‍LightRanger 8 Click is a compact add-on board that contains a ranging sensor with multi-target detection. This board features the VL53L3CX, the latest Time-of-Flight (ToF) product that embeds third-generation FlightSense patented technology from STMicroelectronics.

click Product page

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Click library

• Author : Stefan Nikolic
• Date : jan 2021.
• Type : I2C type

Software Support

We provide a library for the LightRanger8 Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on mikroE github account.

Library Description

‍This library contains API for LightRanger8 Click driver.

Standard key functions :

• lightranger8_cfg_setup Config Object Initialization function.

  void lightranger8_cfg_setup ( lightranger8_cfg_t *cfg );

• lightranger8_init Initialization function.

  err_t lightranger8_init ( lightranger8_t *ctx, lightranger8_cfg_t *cfg );

• lightranger8_default_cfg Click Default Configuration function.

  err_t lightranger8_default_cfg ( lightranger8_t *ctx );

Example key functions :

• lightranger8_set_measurement_timing_budget This function sets the timing budget of the VL53Lx ranging sensor.

  err_t lightranger8_set_measurement_timing_budget ( lightranger8_t *ctx, uint32_t budget_us );

• lightranger8_start_measurement This function enables the range measuring with the adjusted intermeasurement period.

  void lightranger8_start_measurement ( lightranger8_t *ctx, uint32_t period_ms );

• lightranger8_get_distance This function returns the corrected measured distance from the VL53Lx ranging sensor described in milimeters.

  uint16_t lightranger8_get_distance ( lightranger8_t *ctx );

Example Description

‍This demo application shows an example of distance measurement via VL53L3 ranging sensor.

The demo application is composed of two sections :

Application Init

‍Initialization of I2C module, log UART and additional pins.

After driver init, the app powers the device and performs default settings of the ranging sensor including distance mode and timing budget. The optional calibration helps improvement of the accuracy on the targeted distance. This process takes 10 second ( which can by modifed by simply lowering the Delay_ms ( ) value ) so the user can place an object on the exact location. When calibration is finished, device starts the measurement with intermeasurement period set by the user.

void application_init ( void ) {
    log_cfg_t log_cfg;                           
    lightranger8_cfg_t lightranger8_cfg;         
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );
 
    // Click initialization.
 
    lightranger8_cfg_setup( &lightranger8_cfg );
    LIGHTRANGER8_MAP_MIKROBUS( lightranger8_cfg, MIKROBUS_1 );
    err_t init_flag = lightranger8_init( &lightranger8, &lightranger8_cfg );
    if ( init_flag == I2C_MASTER_ERROR ) {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );
 
        for ( ; ; );
    }
 
    lightranger8_power_on( &lightranger8 );
    log_printf( &logger, " Wait until the configuration of the chip is completed...\r\n" );
    if ( lightranger8_default_cfg( &lightranger8 ) != 0 ) {
        log_error( &logger, " Sensor config error. " );
        for ( ; ; );
    }
    lightranger8_set_distance_mode( &lightranger8, LIGHTRANGER8_DISTANCE_MODE_MEDIUM );
    lightranger8_set_measurement_timing_budget( &lightranger8, budget_us );
    Delay_ms ( 1000 );
 
    log_printf( &logger, " -------------------------------------------------------------------------\r\n" );
    log_printf( &logger, " For calibration place an object at %.1f cm distance from sensor.\r\n", ( float )calibration_distance_mm / 10 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    log_printf( &logger, " -------------------------------------------------------------------------\r\n" );
    log_printf( &logger, " ---------------    Sensor calibration is in progress...     ---------------\r\n" );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
    lightranger8_calibrate_offset( &lightranger8, calibration_distance_mm, period_ms, &offset );
    Delay_ms ( 500 );
    
    lightranger8_start_measurement( &lightranger8, period_ms );
    log_printf( &logger, " -------------------------------------------------------------------------\r\n" );
    log_printf( &logger, " -------------    Sensor measurement commencing...    -------------\r\n" );
    Delay_ms ( 100 );
}

Application Task

‍A new data ready is checked as soon as possible which signals

the time required for the ranging sensor to perform the measurement. An acqured distance is shown on the LOG with the 2 seconds delay so the terminal is possible to read.

void application_task ( void ) {
    uint16_t distance;
    
    while ( lightranger8_get_interrupt_state( &lightranger8 ) != 0 ) {
        Delay_1ms();
    }
 
    distance = lightranger8_get_distance( &lightranger8 );
    log_printf( &logger, " ----------------------\r\n" );
    log_printf( &logger, " Distance: %.1f cm \r\n", ( float )distance / 10 );
    lightranger8_system_interrupt_clear ( &lightranger8 );
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
}

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on mikroE github account.

Other mikroE Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.LightRanger8

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all Mikroelektronika compilers.

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