Library Description

The library contains a reading of the state on the interrupt pin. Calculates the number of interruptions in one minute (cpm).

Key functions:

• uint32_t radiation_get_cpm_counter( uint8_t cpm_time ) - Gets CPM ( Counts per minute ).
• void radiation_tick( ) - Tick functions.
• uint8_t radiation_get_int_state( ) - Gets interrupt pin state.

Examples description

The application is composed of three sections :

• System Initialization - Initializes the INT pin required to measure.
• Application Initialization - Initializes the driver
• Application Task - Checks whether command S has been entered
• if so starts radiation measurement. After 60sec it prints the measured radiation in [CPM] and [uSv/h] units.

We used a PB40 sensor with <0.05uCi for the test.

• Radiation units note - The standard unit of radiation dosing in an area is the micro-Sievert/hour (uSv/hr). For this tube, multiply its CPM by 0.0057 to get the equivalent uSv/hr radiation level.

void application_task ( )
{
    uint32_t cpm_value = 0;
    char demo_text[ 50 ];

    uint8_t rsp_drdy;
    char rsp_data;

    rsp_drdy = UART_Rdy_Ptr( );

    if ( rsp_drdy != 0 )
    {
        rsp_data = UART_Rd_Ptr( );

        switch ( rsp_data )
        {
            case 'S' :
            {
                mikrobus_logWrite( " --- PLEASE WAIT FOR THE CALCULATION PROCESS TO COMPLETE ---", _LOG_LINE );
                mikrobus_logWrite( " --- RADIATION MEASUREMENT TAKES 60 SECONDS ---", _LOG_LINE );
                
                radiation_config_timer( );
                cpm_value = radiation_get_cpm_counter( RADIATION_CPM_TIME_60s );

                WordToStr( cpm_value, demo_text );
                mikrobus_logWrite( " Radiation in [CPM]: ", _LOG_TEXT );
                mikrobus_logWrite( demo_text, _LOG_LINE );
                
                FloatToStr( cpm_value * RADIATION_CONSTANT_uSv, demo_text );
                mikrobus_logWrite( " Radiation in [uSv/h]: ", _LOG_TEXT );
                mikrobus_logWrite( demo_text, _LOG_LINE );
                break;
            }
        }
    }
}

Other mikroE Libraries used in the example:

• Conversions library

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.