DIGI POT 3 Click

DIGI POT 3 Click is a versatile and feature-rich digital potentiometer Click with 1024 steps and an internal non-volatile memory (EEMEM), which can be used for storing the wiper position, but also for storing various user data.

Click Product page

Click library

• Author : MikroE Team
• Date : Jan 2020.
• Type : SPI type

Software Support

We provide a library for the DigiPot3 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 DigiPot3 Click driver.

Standard key functions :

• Config Object Initialization function.

  void digipot3_cfg_setup ( digipot3_cfg_t *cfg );

• Initialization function.

  DIGIPOT3_RETVAL digipot3_init ( digipot3_t ctx, digipot3_cfg_t cfg );

• Click Default Configuration function.

  void digipot3_default_cfg ( digipot3_t *ctx );

Example key functions :

• This function stores 16-bit data to the desired EEMEM (non volatile) memory location.

  uint8_t digipot3_store_eemem ( digipot3_t *ctx, uint8_t location_address, uint16_t transfer_data );

• This function executes the desired command.

  uint8_t digipot3_send_command ( digipot3_t *ctx, uint8_t command_byte );

• This function writes 10-bit value to DAC register and determines the wiper position.

  uint8_t digipot3_write_dac ( digipot3_t *ctx, uint16_t value_dac );

Examples Description

This app get value from digital potentiometer and stored to the EEMEM memory.

The demo application is composed of two sections :

Application Init

Initializes device.

void application_init ( void )
{
    log_cfg_t log_cfg;
    digipot3_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 ----\r\n" );

    //  Click initialization.

    digipot3_cfg_setup( &cfg );
    DIGIPOT3_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    digipot3_init( &digipot3, &cfg );

    Delay_ms ( 200 );

    digipot3_read_dac(  &digipot3, &digital_value );
    digipot3_read_eemem( &digipot3, DIGIPOT3_RDAC_EEMEM_LOC, &eemem_value );

    if ( eemem_value != digital_value )
    {
        digipot3_send_command( &digipot3, DIGIPOT3_RESTORE_EEMEM_TO_RDAC_COMM );
    }

    log_printf( &logger, "DIGI POT 3 is initialized \r\n" );
    Delay_ms ( 200 );
}

Application Task

Increments the wiper position by 6dB every 2 seconds. When wiper position reaches the desired value (0x0200), then the wiper position be decremented by 6dB every 2 seconds, until position value reaches the new desired value (0x0002). After that the new position value will be stored to the EEMEM memory, if that value does not already exist in the EEMEM memory.

void application_task ( void )
{
    while ( digital_value < 0x0200 )
    {
        digipot3_send_command( &digipot3, DIGIPOT3_INCREMENT_RDAC_6DB_COMM );
        digipot3_read_dac( &digipot3, &digital_value );
        log_printf( &logger, "DAC value is: %u \r\n", digital_value );
        Delay_ms ( 1000 );
        Delay_ms ( 1000 );
    }

    while ( digital_value > 0x0002 )
    {
        digipot3_send_command( &digipot3, DIGIPOT3_DECREMENT_RDAC_6DB_COMM );
        digipot3_read_dac( &digipot3, &digital_value );
        log_printf( &logger, "DAC value is: %u \r\n", digital_value );
        Delay_ms ( 1000 );
        Delay_ms ( 1000 );
    }

    if ( eemem_value != digital_value )
    {
        digipot3_send_command( &digipot3, DIGIPOT3_STORE_RDAC_TO_EEMEM_COMM );
        eemem_value = digital_value;
    }
} 

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.DigiPot3

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.