Add audible alerts or feedback to your projects with CPT-7502-65-SMT-TR and ATmega1284

Piezoelectric buzzer transducer for generating sound signals in various electronic applications

Published Oct 01, 2024

Click board™

Buzzer Click

Dev. board

EasyAVR v7

Compiler

NECTO Studio

MCU

ATmega1284

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

EasyAVR v7 is the seventh generation of AVR development boards specially designed for the needs of rapid development of embedded applications. It supports a wide range of 16-bit AVR microcontrollers from Microchip and has a broad set of unique functions, such as a powerful onboard mikroProg programmer and In-Circuit debugger over USB. The development board is well organized and designed so that the end-user has all the necessary elements in one place, such as switches, buttons, indicators, connectors, and others. With four different connectors for each port, EasyAVR v7 allows you to connect accessory boards, sensors, and custom electronics more

efficiently than ever. Each part of the EasyAVR v7 development board contains the components necessary for the most efficient operation of the same board. An integrated mikroProg, a fast USB 2.0 programmer with mikroICD hardware In-Circuit Debugger, offers many valuable programming/debugging options and seamless integration with the Mikroe software environment. Besides it also includes a clean and regulated power supply block for the development board. It can use a wide range of external power sources, including an external 12V power supply, 7-12V AC or 9-15V DC via DC connector/screw terminals, and a power source via the USB Type-B (USB-B)

connector. Communication options such as USB-UART and RS-232 are also included, alongside the well-established mikroBUS™ standard, three display options (7-segment, graphical, and character-based LCD), and several different DIP sockets which cover a wide range of 16-bit AVR MCUs. EasyAVR v7 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

Microcontroller Overview

MCU Card / MCU

Architecture

AVR

MCU Memory (KB)

128

Silicon Vendor

Microchip

Pin count

RAM (Bytes)

16384

Used MCU Pins

mikroBUS™ mapper

RST

ID COMM

PA5

SCK

MISO

MOSI

Power Supply

3.3V

Ground

GND

PWM Signal

PD4

PWM

INT

SCL

SDA

Power Supply

Ground

GND

Take a closer look

Click board™ Schematic

Step by step

Project assembly

EasyAVR v7 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the EasyAVR v7 as your development board.

NECTO Output Selection Step Image hardware assembly

In the advanced settings, pay special attention to the Redirect standard output field. By default, it is set to Application output as the method of displaying final results. To show results via a UART terminal, select the “UART” option in that field and click the “SAVE” button. You will be returned to the Compiler field, and now you can move on to the next step by pressing the “NEXT” button.

Buck 22 Click front image hardware assembly

EasyAVR v7 MB 1 - upright/background hardware assembly

NECTO Compiler Selection Step Image hardware assembly

Necto DIP image step 7 hardware assembly

EasyPIC PRO v7a Display Selection 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