Library Description

The library covers all the necessary functions to control Fingerprint 3 Click board. A library performs the communication with the device via UART interface.

Key functions:

• void fingerprint3_parser_rsp ( fingerprint3_rsp_t *response ) - Response parser function.
• uint8_t fingerprint3_byte_ready ( void ) - Check for new byte received.
• void fingerprint3_uart_write ( uint8_t *tx_data, uint8_t n_bytes ) - Uart write function.

Examples description

The application is composed of three sections :

• System Initialization - Initializes UART used for communication and another UART bus used for data logging.
• Application Initialization - Initializes UART driver, check the sensor, verify module password and then start registering a new fingerprint pattern.
• Application Task - (code snippet) - This is an example that demonstrates the use of the Fingerprint 3 Click board. Fingerprint 3 Click stores the new fingerprint pattern which shortly after compares with new fingerprint scans for a match, infinitely. Results are being sent to the Usart Terminal where you can track their changes.

void application_task ( )
{
    if ( fingerprint3_finger_indicator( ) == FINGERPRINT3_DETECT_FINGER )
    {
        fingerprint3_buf_clear( );
        mikrobus_logWrite( "---------------------------------", _LOG_LINE );
        mikrobus_logWrite( " >>> Verification in progress... ", _LOG_LINE );
        Delay_ms( 2000 );

        fingerprint3_uart_write( &gen_img[ 0 ], 12 );
        Delay_ms( 500 );
        fingerprint3_parser_rsp( &rsp );
        Delay_ms( 100 );

        if ( rsp.confirm_code == FINGERPRINT3_OK )
        {
            fingerprint3_uart_write( &img_2_tz_2[ 0 ], 13 );
            Delay_ms( 500 );
            fingerprint3_buf_clear( );
        }

        fingerprint3_uart_write( ®_model[ 0 ], 12 );
        Delay_ms( 100 );
        fingerprint3_buf_clear( );

        fingerprint3_uart_write( &fingerprint_match[ 0 ], 12 );
        Delay_ms( 500 );
        fingerprint3_parser_rsp( &rsp );
        fingerprint3_display_match_score( );
        Delay_ms( 3000 );

        mikrobus_logWrite( "  >>> Comparing Fingerprints <<< ", _LOG_LINE );
        mikrobus_logWrite( "- - - - - - - - - - - - - - - - -", _LOG_LINE );
        mikrobus_logWrite( " Place your finger on the sensor ", _LOG_LINE );
    }
    else
    {
        fingerprint3_uart_write( &aura_led_config_purple[ 0 ], 16 );
        Delay_ms( 2000 );
        fingerprint3_buf_clear( );
    }
}

• void fingerprint3_display_rsp ( void ) - Display response function.
• void fingerprint3_display_match_score ( void ) - Display match score function.
• void log_write ( uint8_t *str_buf, uint8_t str_type ) - Wrapper mikrobus_logWrite for driver function.
• void byte_to_str ( uint8_t byte_buf, uint8_t *log_text ) - Wrapper ByteToStr for driver function.
• void byte_to_hex ( uint8_t byte_buf, uint8_t *log_text ) - Wrapper ByteToHex for driver function.
• void long_word_to_hex ( uint32_t long_word_buf, uint8_t *log_text ) - Wrapper LongWordToHex for driver function.

Other mikroE Libraries used in the example:

• 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.