Library Description

Library contains function for getting INT pin state, for getting and setting registers via I2C, for presenting and writing password, for enabling/disabling mailbox and RF functionalities and for device initialization.

Key functions:

• uint8_t nfcextend_password_present ( uint8_t *password_bytes ) - Presenting password to device.
• uint8_t nfcextend_init ( void ) - Initializing the device.
• uint8_t nfcextend_enable_mailbox ( uint8_t enable_mailbox ) - Enabling or disabling mailbox.

Examples description

The application is composed of three sections :

• System Initialization - Initializes GPIO pins, I2C and LOG modules.
• Application Initialization - Initializes I2C driver, presents password to the device and initializes the device.
• Application Task - Checks if RF placed a message to mailbox and if it did, checks message length and logs message bytes.

void application_init ( )
{
    nfcextend_i2c_driver_init( (nfcextend_obj_t)&_MIKROBUS1_GPIO, (nfcextend_obj_t)&_MIKROBUS1_I2C, NFCEXTEND_I2C_SLAVE_ADDRESS );
    Delay_ms( 500 );
    
    nfcextend_password_present( &default_password[ 0 ] );
    Delay_ms( 100 );

    init_status_flag = nfcextend_init( );
    Delay_ms( 100 );

    if ( init_status_flag == 1 )
    {
        mikrobus_logWrite( "> App init fail", _LOG_LINE );
    }
    else if ( init_status_flag == 0 )
    {
        mikrobus_logWrite( "> App init done", _LOG_LINE );
    }
}

Additional Functions :

• nfcextend_wait_for_int( void ) - waits for INT pin to go LOW and than HIGH for time period of 300ms

Other mikroE Libraries used in the example:

• I2C
• UART
• Conversions

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.