Zero-Cross Click

Zero-Cross Click is a compact add-on board that has the ability to detect the change from positive to negative or negative to a positive level of a sinusoidal waveform. This board features circuitry that provides Zero Crossing Detection (ZCD). Whenever the sine wave crosses the ground potential, the output shifts from HIGH logic to LOW or vice-versa.

Click Product page

Click library

• Author : Stefan Ilic
• Date : May 2023.
• Type : GPIO type

Software Support

We provide a library for the Zero-Cross 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 Zero-Cross Click driver.

Standard key functions :

• zerocross_cfg_setup Config Object Initialization function.

  void zerocross_cfg_setup ( zerocross_cfg_t *cfg );

• zerocross_init Initialization function.

  err_t zerocross_init ( zerocross_t *ctx, zerocross_cfg_t *cfg );

Example key functions :

• zerocross_pin_read Zero-Cross pin reading function.

  uint8_t zerocross_pin_read ( zerocross_t *ctx );

• zerocross_get_freq Zero-Cross frequency reading function.

  void zerocross_get_freq ( zerocross_t *ctx, float *freq );

Example Description

This example demonstrates the use of the Zero-Cross Click board.

The demo application is composed of two sections :

Application Init

Initialization of the log UART and basic Click initialisation.

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    zerocross_cfg_t zerocross_cfg;  /**< Click config object. */

    /** 
     * 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.
    zerocross_cfg_setup( &zerocross_cfg );
    ZEROCROSS_MAP_MIKROBUS( zerocross_cfg, MIKROBUS_1 );
    if ( DIGITAL_OUT_UNSUPPORTED_PIN == zerocross_init( &zerocross, &zerocross_cfg ) ) 
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }

    log_info( &logger, " Application Task " );
}

Application Task

Reading frequency value approximately once every second.

void application_task ( void ) 
{
    float freq_val = 0;
    zerocross_get_freq( &zerocross, &freq_val );
    log_printf( &logger, " Freq %.2f Hz \n\r", freq_val );
}

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.ZeroCross

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.