Compass 3 Click

Compass 3 Click is an expansion board that can measure the three-axis magnetic field which is perfect for implementation in applications such as electric compasses. This board features MMC5883MA, a complete 3-axis magnetic sensor with signal processing from MEMSIC.

Click Product page

Click library

• Author : Jovan Stajkovic
• Date : Jan 2020.
• Type : I2C type

Software Support

We provide a library for the Compass3 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 Compass3 Click driver.

Standard key functions :

• Config Object Initialization function.

  void compass3_cfg_setup ( compass3_cfg_t *cfg );

• Initialization function.

  COMPASS3_RETVAL compass3_init ( compass3_t ctx, compass3_cfg_t cfg );

• Click Default Configuration function.

  void compass3_default_cfg ( compass3_t *ctx );

Example key functions :

• Measures magnetic field surrounding the device.

  void compass3_full_measurement ( compass3_t ctx, float x_val, float y_val, float z_val );

• Function is used to measure temperature.

  float compass3_read_temp ( compass3_t *ctx );

• Function checks interrupt occurence.

  uint8_t compass3_check_int ( compass3_t *ctx );

Examples Description

This demoapp measures the magnetic field surrounding the device.

The demo application is composed of two sections :

Application Init

Initalizes I2C driver and Click driver, performs check, applies default setup and writes an initial log.

void application_init ( void )
{
    log_cfg_t log_cfg;
    compass3_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_printf( &logger, "---- Application Init ----\r\n" );

    //  Click initialization.

    compass3_cfg_setup( &cfg );
    COMPASS3_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    compass3_init( &compass3, &cfg );
    Delay_ms ( 100 );

    compass3_generic_read( &compass3, COMPASS3_DEVICE_ID, &test_val, 1 );

    if ( test_val == COMPASS3_DEVICE_ID_NUM )
    {
        log_printf( &logger, "--------------------\r\n" );
        log_printf( &logger, "   Compass 3 Click  \r\n" );
        log_printf( &logger, "--------------------\r\n" );
    }
    else
    {
        log_printf( &logger, "   Fatal error!!!   \r\n" );
        for ( ; ; );
    }

    compass3_default_cfg ( &compass3 );
    Delay_ms ( 100 );
}

Application Task

This example demonstrates the use of Compass 3 Click board by measuring the magnetic field surrounding the device.

void application_task ( void )
{
    if ( compass3_check_int( &compass3 ) == COMPASS3_INTERRUPT )
    {
        compass3_full_measurement ( &compass3, &x_val, &y_val, &z_val );

        log_printf( &logger,"  X-axis : %2.f mG\r\n", x_val );
        log_printf( &logger,"  Y-axis : %2.f mG\r\n", y_val );
        log_printf( &logger,"  Z-axis : %2.f mG\r\n", z_val );

        Delay_ms ( 1000 );
        log_printf( &logger, "--------------------\r\n" );
    }
}

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.Compass3

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.