MUX 4 click

MUX 4 Click is a compact add-on board that contains a precise analog multiplexing IC. This board features the 74HC4851, 8-channel analog multiplexer/demultiplexer with injection-current effect control from Nexperia USA Inc.

click Product page

Click library

• Author : Stefan Filipovic
• Date : Jul 2021.
• Type : ADC type

Software Support

We provide a library for the MUX4 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 MUX4 Click driver.

Standard key functions :

• mux4_cfg_setup Config Object Initialization function.

  void mux4_cfg_setup ( mux4_cfg_t *cfg );

• mux4_init Initialization function.

  err_t mux4_init ( mux4_t *ctx, mux4_cfg_t *cfg );

Example key functions :

• mux4_read_an_pin_voltage This function reads results of AD conversion of the AN pin and converts them to proportional voltage level.

  err_t mux4_read_an_pin_voltage ( mux4_t *ctx, float *data_out );

• mux4_enable_input This function enable or disables analog inputs.

  void mux4_enable_input ( mux4_t *ctx, uint8_t en_state );

• mux4_select_input This function selects which input channel signal is being forwarded to the AN/EXT pin.

  void mux4_select_input ( mux4_t *ctx, uint8_t input );

Example Description

This example demonstrates the use of MUX 4 click board.

The demo application is composed of two sections :

Application Init

Initializes the driver and enables analog inputs.

void application_init ( void )
{
    log_cfg_t log_cfg;    /**< Logger config object. */
    mux4_cfg_t mux4_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 );
    Delay_ms ( 100 );
    log_info( &logger, " Application Init " );

    // Click initialization.

    mux4_cfg_setup( &mux4_cfg );
    MUX4_MAP_MIKROBUS( mux4_cfg, MIKROBUS_1 );
    if ( ADC_ERROR == mux4_init( &mux4, &mux4_cfg ) )
    {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }

    mux4_enable_input( &mux4, MUX4_ENABLE_INPUT );
}

Application Task

Reads the voltage from all input channels and displays the values of each channel on the USB UART approximately every second.

void application_task ( void )
{
    float mux4_an_voltage = 0;

    for ( uint8_t cnt = MUX4_SELECT_INPUT_1; cnt <= MUX4_SELECT_INPUT_8; cnt++ )
    {
        mux4_select_input( &mux4, cnt );
        Delay_ms ( 10 );
        if ( ADC_ERROR != mux4_read_an_pin_voltage ( &mux4, &mux4_an_voltage ) ) 
        {
            log_printf( &logger, " CH%u Voltage : %.3f V\r\n", ( uint16_t ) cnt, mux4_an_voltage );
        }
    }
    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.MUX4

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.