Clock Gen 4 Click

Clock Gen 4 Click is a compact add-on board that contains both a clock generator and a multiplier/jitter reduced clock frequency synthesizer. This board features the CS2200-CP, an analog PLL architecture comprised of a Delta-Sigma fractional-N frequency synthesizer from Cirrus Logic. This clocking device utilizes a programmable phase lock loop and allows frequency synthesis and clock generation from a stable reference clock. It generates a low-jitter PLL clock from an external crystal, supports both I²C and SPI for full software control, and also has configurable auxiliary clock output. This Click board™ is suitable for MCU clock source, or in applications like digital effects processors, digital mixing consoles, and many more.

Click Product page

Click library

• Author : Jelena Milosavljevic
• Date : Jul 2021.
• Type : I2C/SPI type

Software Support

We provide a library for the ClockGen4 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 ClockGen4 Click driver.

Standard key functions :

• clockgen4_cfg_setup Config Object Initialization function.

  void clockgen4_cfg_setup ( clockgen4_cfg_t *cfg );

• clockgen4_init Initialization function.

  err_t clockgen4_init ( clockgen4_t *ctx, clockgen4_cfg_t *cfg );

• clockgen4_default_cfg Click Default Configuration function.

  err_t clockgen4_default_cfg ( clockgen4_t *ctx );

Example key functions :

• clockgen4_dev_ctl Function is used to write to device control register in order to apply settings.

  void clockgen4_dev_ctl ( clockgen4_t *ctx, uint8_t dev_ctl );

• clockgen4_dev_cfg Function is used to write to device configuration 1 register in order to apply settings.

  void clockgen4_dev_cfg ( clockgen4_t *ctx, uint8_t dev_cfg );

• clockgen4_glob_cfg Function is used to write to function configuration 2 register in order to apply settings.

  void clockgen4_glob_cfg ( clockgen4_t *ctx, uint8_t glob_cfg );

Example Description

This example demonstrates the uses of Clock Gen 4 Click which is based on CS2200-CP for changing the channel clock. The CS2200-CP is an extremely versatile system clocking device that utilizes a programmable phase lock loop. The CS2200-CP is based on an analog PLL architecture and this architecture allows for frequency synthesis and clock generation from a stable reference clock. The CS2200-CP supports both I²C and SPI for full software control.

The demo application is composed of two sections :

Application Init

Initializes I2C and SPI, sets CS pin as output and starts to write log, applies default settings and adjusted ratio to obtain a frequency.

void application_init ( void ){
    log_cfg_t log_cfg;                     /**< Logger config object. */
    clockgen4_cfg_t clockgen4_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 " );

    Delay_ms ( 100 );
    log_printf( &logger, "---------------------" );
    log_printf( &logger, "  Clock Gen 4 Click  " );
    log_printf( &logger, "---------------------" );

    // Click initialization.
    clockgen4_cfg_setup( &clockgen4_cfg );
    CLOCKGEN4_MAP_MIKROBUS( clockgen4_cfg, MIKROBUS_1 );
    err_t init_flag  = clockgen4_init( &clockgen4, &clockgen4_cfg );
    if ( ( I2C_MASTER_ERROR == init_flag ) || ( SPI_MASTER_ERROR == init_flag ) ) {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }

    clockgen4_default_cfg ( &clockgen4 );
    log_info( &logger, " Application Task " );
    Delay_ms ( 100 );
}

Application Task

Clock Gen 4 Click is used in this example to generate and change the clock on the output channel.

void application_task ( void ){
    clockgen4_dev_ctl ( &clockgen4, CLOCKGEN4_AUX_OUT_DIS | CLOCKGEN4_CLK_OUT_EN );
    log_printf( &logger, "  PLL Clock          \r\n" );
    log_printf( &logger, "  output enabled!    \r\n" );
    log_printf( &logger, "---------------------\r\n" );
    Delay_ms ( 1000 );

    clockgen4_dev_ctl ( &clockgen4, CLOCKGEN4_AUX_OUT_EN | CLOCKGEN4_CLK_OUT_DIS );
    log_printf( &logger, "  AUX Clock          \r\n" );
    log_printf( &logger, "  output enabled!    \r\n" );
    log_printf( &logger, "---------------------\r\n" );
    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.ClockGen4

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.