Add audible alerts or feedback to your projects with CPT-7502-65-SMT-TR and PIC18F57Q43

Piezoelectric buzzer transducer for generating sound signals in various electronic applications

Buzzer Click with Curiosity Nano with PIC18F57Q43

Published Oct 01, 2024

Click board™

Buzzer Click

Dev. board

Curiosity Nano with PIC18F57Q43

Compiler

NECTO Studio

MCU

PIC18F57Q43

Generate audible alerts for security systems or sound signals for notifications or reminders in various projects

Hardware Overview

How does it work?

Buzzer Click is based on the CPT-7502-65-SMT-TR, a piezoelectric buzzer transducer from CUI Devices designed for efficient and reliable sound output in a surface-mount form factor. The buzzer has a compact square shape with dimensions of 7.5x7.5x2mm and offers a sound pressure level of 65dB, ensuring clear and noticeable sound in various applications. It is externally driven, meaning it requires an external circuit for activation, which is placed on this board. It consumes a low current of only 1mA, making it suitable for battery-powered devices. This Click board™ is designed in a unique format supporting the newly introduced MIKROE feature called "Click

Snap." Unlike the standardized version of Click boards, this feature allows the main sensor area to become movable by breaking the PCB, opening up many new possibilities for implementation. Thanks to the Snap feature, the CPT-7502-65-SMT-TR can operate autonomously by accessing its signals directly on the pins marked 1-8. Additionally, the Snap part includes a specified and fixed screw hole position, enabling users to secure the Snap board in their desired location. This Click board™ uses an N-channel MOSFET to control the buzzer via a PWM signal, allowing for precise modulation of the sound's frequency and intensity. When the PWM signal is applied, the MOSFET enables the flow of

current through the piezoelectric buzzer, activating it and producing sound. This setup provides flexibility in controlling the buzzer's output, making it a versatile solution for sound signaling in various electronic projects. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used as a reference for further development.

Features overview

Development board

PIC18F57Q43 Curiosity Nano evaluation kit is a cutting-edge hardware platform designed to evaluate microcontrollers within the PIC18-Q43 family. Central to its design is the inclusion of the powerful PIC18F57Q43 microcontroller (MCU), offering advanced functionalities and robust performance. Key features of this evaluation kit include a yellow user LED and a responsive

mechanical user switch, providing seamless interaction and testing. The provision for a 32.768kHz crystal footprint ensures precision timing capabilities. With an onboard debugger boasting a green power and status LED, programming and debugging become intuitive and efficient. Further enhancing its utility is the Virtual serial port (CDC) and a debug GPIO channel (DGI

GPIO), offering extensive connectivity options. Powered via USB, this kit boasts an adjustable target voltage feature facilitated by the MIC5353 LDO regulator, ensuring stable operation with an output voltage ranging from 1.8V to 5.1V, with a maximum output current of 500mA, subject to ambient temperature and voltage constraints.

PIC18F57Q43 Curiosity Nano double side image

Microcontroller Overview

MCU Card / MCU

Architecture

PIC

MCU Memory (KB)

128

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

8196

You complete me!

Accessories

Curiosity Nano Base for Click boards is a versatile hardware extension platform created to streamline the integration between Curiosity Nano kits and extension boards, tailored explicitly for the mikroBUS™-standardized Click boards and Xplained Pro extension boards. This innovative base board (shield) offers seamless connectivity and expansion possibilities, simplifying experimentation and development. Key features include USB power compatibility from the Curiosity Nano kit, alongside an alternative external power input option for enhanced flexibility. The onboard Li-Ion/LiPo charger and management circuit ensure smooth operation for battery-powered applications, simplifying usage and management. Moreover, the base incorporates a fixed 3.3V PSU dedicated to target and mikroBUS™ power rails, alongside a fixed 5.0V boost converter catering to 5V power rails of mikroBUS™ sockets, providing stable power delivery for various connected devices.

Used MCU Pins

mikroBUS™ mapper

RST

ID COMM

PD4

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

PWM Signal

PB0

PWM

INT

SCL

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

Curiosity Nano Base for Click boards front image hardware assembly

Start by selecting your development board and Click board™. Begin with the Curiosity Nano with PIC18F57Q43 as your development board.

Barometer 13 Click front image hardware assembly

PIC18F57Q43 Curiosity Nano front image hardware assembly

Curiosity Nano with PICXXX MB 1 - upright/background hardware assembly

PIC18F57Q43 Curiosity MCU Step hardware assembly

Necto No Display image step 8 hardware assembly

Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

1. Application Output - In Debug mode, the 'Application Output' window enables real-time data monitoring, offering direct insight into execution results. Ensure proper data display by configuring the environment correctly using the provided tutorial.

2. UART Terminal - Use the UART Terminal to monitor data transmission via a USB to UART converter, allowing direct communication between the Click board™ and your development system. Configure the baud rate and other serial settings according to your project's requirements to ensure proper functionality. For step-by-step setup instructions, refer to the provided tutorial.

3. Plot Output - The Plot feature offers a powerful way to visualize real-time sensor data, enabling trend analysis, debugging, and comparison of multiple data points. To set it up correctly, follow the provided tutorial, which includes a step-by-step example of using the Plot feature to display Click board™ readings. To use the Plot feature in your code, use the function: plot(*insert_graph_name*, variable_name);. This is a general format, and it is up to the user to replace 'insert_graph_name' with the actual graph name and 'variable_name' with the parameter to be displayed.

Software Support

Library Description

This library contains API for Buzzer Click driver.

Key functions:

buzzer_play_sound - This function plays sound on the buzzer.

Open Source

Code example

The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.

/*!
 * @file main.c
 * @brief Buzzer Click example
 *
 * # Description
 * This example demonstrates the use of Buzzer click board by playing
 * the Imperial March melody on the buzzer.
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * Initializes the driver and logger.
 * 
 * ## Application Task  
 * Plays the Imperial March melody. Also logs an appropriate message on the USB UART.
 * 
 * @note
 * The minimal PWM Clock frequency required for this example is the frequency of tone C6 - 1047 Hz. 
 * So, in order to run this example and play all tones correctly, the user will need to decrease 
 * the MCU's main clock frequency in MCU Settings for the certain architectures
 * in order to get the required PWM clock frequency.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "buzzer.h"

static buzzer_t buzzer;
static log_t logger;

/**
 * @brief Buzzer imperial march function.
 * @details This function plays the Imperial March melody on the buzzer
 * at the selected volume level.
 * @param[in] volume : Buzz sound level. ( min = 1, max = 100 )
 * @return None.
 * @note None.
 */
static void buzzer_imperial_march ( uint8_t volume );

void application_init ( void ) 
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    buzzer_cfg_t buzzer_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 );
    log_info( &logger, " Application Init " );

    // Click initialization.
    buzzer_cfg_setup( &buzzer_cfg );
    BUZZER_MAP_MIKROBUS( buzzer_cfg, MIKROBUS_1 );
    if ( PWM_ERROR == buzzer_init( &buzzer, &buzzer_cfg ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void ) 
{
    log_printf( &logger, " Playing the Imperial March melody...\r\n" );
    buzzer_imperial_march( BUZZER_VOLUME_MAX ); 
    Delay_ms ( 1000 );
    Delay_ms ( 1000 );
}

int main ( void ) 
{
    /* Do not remove this line or clock might not be set correctly. */
    #ifdef PREINIT_SUPPORTED
    preinit();
    #endif
    
    application_init( );
    
    for ( ; ; ) 
    {
        application_task( );
    }

    return 0;
}

static void buzzer_imperial_march ( uint8_t volume )
{
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_HALF );
    Delay_ms ( BUZZER_NOTE_LEN_HALF );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_E7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_E7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_E7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F7, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Ab6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_HALF );
    Delay_ms ( BUZZER_NOTE_LEN_HALF );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Ab7, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_G7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Gb7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_E7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F7, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Bb6, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Eb7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_D7, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Db7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_B6, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Ab6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_E7, volume, BUZZER_NOTE_LEN_HALF );
    Delay_ms ( BUZZER_NOTE_LEN_HALF );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Ab7, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_G7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Gb7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_E7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F7, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Bb6, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Eb7, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_D7, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Db7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_B6, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Ab6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    
    buzzer_play_sound( &buzzer, BUZZER_NOTE_A6, volume, BUZZER_NOTE_LEN_QUARTER );
    Delay_ms ( BUZZER_NOTE_LEN_QUARTER );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_F6, volume, BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_EIGHTH + BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_C7, volume, BUZZER_NOTE_LEN_SIXTEENTH );
    Delay_ms ( BUZZER_NOTE_LEN_SIXTEENTH );
    buzzer_play_sound( &buzzer, BUZZER_NOTE_Ab6, volume, BUZZER_NOTE_LEN_HALF );
    Delay_ms ( BUZZER_NOTE_LEN_HALF );
}

// ------------------------------------------------------------------------ END