Mikroelektronika MIKROE-742 데이터 시트

The example is a simple demonstration of how to use the Sound Library for playing tones on a
piezo speaker.

program Sound;

// Sound connections
var Sound_Play_Pin : sbit at PORTC.B3;
var Sound_Play_Pin_direction : sbit at DDRC.B3;
// End Sound connections

procedure Tone1();

Sound_Play(500, 200);               // Frequency = 500Hz, Duration = 200ms

procedure Tone2();

Sound_Play(555, 200);               // Frequency = 555Hz, Duration = 200ms

procedure Tone3();

Sound_Play(625, 200);               // Frequency = 625Hz, Duration = 200ms

procedure Melody();                          // Plays the melody "Yellow house"

Tone1(); Tone2(); Tone3(); Tone3();

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- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 6

procedure Sound_Play(freq_in_Hz: word; duration_ms: word); 

Nothing.

Generates the square wave signal on the appropriate pin.

Parameters : 

- 

freq_in_Hz

: signal frequency in Hertz (Hz) 

- 

duration_ms

: signal duration in miliseconds (ms) 

In order to hear the sound, you need a piezo speaker (or other hardware) on
designated port. Also, you must call Sound_Init to prepare hardware for output
before using this function.

// Play sound of 1KHz in duration of 100ms

Sound_Play(1000, 100);