lightranger4

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Light Ranger 4 click

Light Ranger 4 click is an accurate distance measurement Click board based on a ToF (Time of Flight) measurement principle.

click Product page

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Click library

• Author : Katarina Perendic
• Date : okt 2019.
• Type : I2C type

Software Support

We provide a library for the LightRanger4 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 form compilers IDE(recommended way), or downloaded from our LibStock, or found on mikroE github account.

Library Description

This library contains API for LightRanger4 Click driver.

Standard key functions :

• Config Object Initialization function.

void lightranger4_cfg_setup ( lightranger4_cfg_t *cfg );

• Initialization function.

LIGHTRANGER4_RETVAL lightranger4_init ( lightranger4_t *ctx, lightranger4_cfg_t *cfg );

• Click Default Configuration function.

void lightranger4_default_cfg ( lightranger4_t *ctx );

Example key functions :

• Function that checks whether the new data is ready for reading

uint8_t lightranger4_new_data_ready ( lightranger4_t *ctx );

• Function reads distance of the object in front of the sensor

uint16_t lightranger4_get_distance ( lightranger4_t *ctx );

• Function for starts power ON procedure

void lightranger4_power_on ( lightranger4_t *ctx );

Examples Description

Demo application is used to shows basic controls LightRanger 4 click

The demo application is composed of two sections :

Application Init

Configuring clicks and log objects. Settings the click in the default configuration, adjusts the LONG mode (distance measurement up to 4 meters), sets the time budget and start measurement with the adjustment of inter measurements period.

void application_init ( void )
{
    log_cfg_t log_cfg;
    lightranger4_cfg_t cfg;

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, "---- Application Init ----" );

    //  Click initialization.

    lightranger4_cfg_setup( &cfg );
    LIGHTRANGER4_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    lightranger4_init( &lightranger4, &cfg );

    lightranger4_power_on( &lightranger4 );
    log_info( &logger, "--- Wait until the configuration of the chip is completed ---" );

    lightranger4_default_cfg( &lightranger4 );
    lightranger4_set_distance_mode( &lightranger4, LR4_DISTANCE_MODE_LONG );
    lightranger4_set_measurement_timing_budget( &lightranger4, 1000 );
    lightranger4_start_measurement( &lightranger4, 20 );

    log_info( &logger, "--- Sensor start measurement ---" );
    Delay_100ms( );
}

Application Task

Reads the distance of the object in front of the sensor and logs distance to USBUART every 500 ms.

void application_task ( void )
{
    uint16_t distance;
    uint8_t m_status;

    //  Task implementation.

    while ( lightranger4_new_data_ready( &lightranger4 ) != 0 )
    {
        Delay_1ms();
    }

    distance = lightranger4_get_distance( &lightranger4 );
    log_printf( &logger, "** Distance: %d mm \r\n", distance );

    m_status = lightranger4_get_range_status( &lightranger4 );
    switch ( m_status )
    {
        case LR4_MRESP_SIGNAL_FAIL:
        {
            log_info( &logger, "Signal fail." );
            break;
        }
        case LR4_MRESP_PHASE_OUT_OF_VALID_LIMITS:
        {
            log_info( &logger, "Phase out of valid limits" );
            break;
        }
        case LR4_MRESP_SIGMA_FAIL:
        {
            log_info( &logger, "Sigma Fail. " );
            break;
        }
        case LR4_MRESP_WRAP_TARGET_FAIL:
        {
            log_info( &logger, "Wrap target fail." );
            break;
        }
        case LR4_MRESP_MINIMUM_DETECTION_THRESHOLD:
        {
            log_info( &logger, "Target is below minimum detection threshold. " );
            break;
        }
    }
    Delay_ms ( 500 );
}

The full application code, and ready to use projects can be installed directly form compilers IDE(recommneded) or found on LibStock page or mikroE GitHub accaunt.

Other mikroE Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.LightRanger4

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. The terminal available in all Mikroelektronika compilers, or any other terminal application of your choice, can be used to read the message.

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