Analog Key Click

Analog Key Click is an analog keyboard on a Click board�. It contains six tactile pushbuttons, used to select one of six different voltage levels.

Click Product page

Click library

• Author : MikroE Team
• Date : Dec 2019.
• Type : ADC type

Software Support

We provide a library for the AnalogKey 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 AnalogKey Click driver.

Standard key functions :

• Config Object Initialization function.

  void analogkey_cfg_setup ( analogkey_cfg_t *cfg );

• Initialization function.

  ANALOGKEY_RETVAL analogkey_init ( analogkey_t ctx, analogkey_cfg_t cfg );

Example key functions :

• This function returns which button is pressed.

  uint8_t analogkey_get_key ( analogkey_t* ctx, uint16_t adc_value );

• This function sets the resolution.

  void analogkey_set_resolution ( analogkey_t* ctx, uint8_t resolution );

Examples Description

This example logs which button is pressed.

The demo application is composed of two sections :

Application Init

Initializes driver.

void application_init ( void )
{
    log_cfg_t log_cfg;
    analogkey_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 ----" );

    analogkey_cfg_setup( &cfg );
    ANALOGKEY_MAP_MIKROBUS( cfg, MIKROBUS_1 );

    analogkey_set_resolution( &analogkey, ANALOGKEY_ADC_RESOLUTION_12bit );

    analogkey_init( &analogkey, &cfg );
    Delay_ms ( 100 );

    log_printf(&logger, " Press the button :D\r\n ");

}

Application Task

Reads ADC value and detects which button is pressed based on that value.

void application_task ( void )
{
    float an_voltage = 0;
    analogkey_key_id_t key;
    float an_average = 0;

    an_voltage = analogkey_read_voltage( &analogkey );

    if ( an_voltage > 0.2 )
    {
        an_average += an_voltage / ANALOGKEY_N_SAMPLES;
        for ( uint8_t cnt = 0; cnt < ANALOGKEY_N_SAMPLES - 1; cnt++ )
        {
            an_voltage = analogkey_read_voltage( &analogkey );

            an_average += an_voltage / ANALOGKEY_N_SAMPLES;
        }
    }

    if ( ( key = analogkey_get_key( &analogkey, an_average ) ) != ANALOGKEY_TOUCH_KEY_NONE )
    {
        log_printf( &logger, " T%u is pressed.\r\n", (uint16_t)key );

        while ( analogkey_read_voltage( &analogkey ) > 0.2 ) {
             Delay_ms ( 1 );   
        }

        log_printf( &logger, " T%u is released.\r\n", (uint16_t)key );
        Delay_ms ( 10 );
    }
} 

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.AnalogKey

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.