Lesson nr.20-Sound generation

Hardware setup:

Circuit Diagram:
For those who want to build it on their own breadboard or other platform, here is the electronic scheme built in Eagle Cad, free version:

Software:
Here is the C program written for MikroC PRO for PIC 2010 (version v4.15).

/*
'*******************************************************************************
'  Lesson nr.20:
'          Sound generation.
'  Done by:
'          Aureliu Raducu Macovei, 2010.
'  Description:
'          In this experiment we will work with sounds.
'          I'll show how to generate and make sound helped by microcontroller 
'          and some buttons.
'          Communication with the buzzer will be performed  at PORT RB3 ( as PWM mode).
'          The Push buttons are connected to PORT RA4 (generates Tone1), RA6
'          (generates Tone2) and RA7(generates melody2). 
'          Of course we need pull-up resistors (4k7 is required).
'  Test configuration:
'    MCU:                        PIC16F628A
'    Test.Board:                 WB-106 Breadboard 2420 dots
'    SW:                         MikroC PRO for PIC 2010 (version v4.15)
'  Configuration Word
'    Oscillator:                 INTOSC:I/O on RA.6, I/O on RA.7
'    Watchdog Timer:             OFF
'    Power up Timer:             Disabled
'    Master Clear Enable:        Enabled
'    Browun Out Detect:          Enabled
'    Low Voltage Program:        Disabled
'    Data EE Read Protect:       Disabled
'    Code Protect:               OFF
'*******************************************************************************
*/
void Tone1()
{
 Sound_Play(5000, 1000);         // Frequency = 659Hz, duration = 250ms
}

void Tone2() 
{
 Sound_Play(4000, 1000);         // Frequency = 698Hz, duration = 250ms
 }

void Tone3() 
{
 Sound_Play(3000, 1000);         // Frequency = 784Hz, duration = 250ms
 }

void Melody1()                  // Make funny melody 1;
{
 Tone1(); Tone2(); Tone3();
 Tone3(); Tone2(); Tone1();
 Tone1(); Tone3(); Tone2();
 Tone3(); Tone2(); Tone1(); Tone3();
 Tone1(); Tone2(); Tone3();
 Tone3(); Tone1(); Tone2(); Tone2(); Tone1();
 }

void ToneA()                    // Tone A;
{
 Sound_Play(1618, 50);          // (frequency, duration)
}

void ToneB()                    // Tone B;
{
 Sound_Play(1918, 50);          // (frequency, duration)
}

void ToneC()                    // Tone C;
{
 Sound_Play(2212, 50);          // (frequency, duration)
}

void Melody2()                  // Make funny melody 2;
{
 unsigned short i;
 for (i = 12; i > 0; i--)
 {
  ToneA(); ToneB(); ToneC();
  }
 }

void main() 
{
 CMCON |=7;                     // Disable comparator
 TRISB = 0xF0;                  // Pins RB7-RB4 are configured as inputs,
                                // RB3 is configured as an output
 Sound_Init(&PORTB, 3);
 Sound_Play(5000,100);          // Start with this song (frequency, duration)

 while (1)                      // infinite loop
 {
  if (Button(&PORTA,4,1,0))     // RB4 generates Tone1
  Tone1();
  
  if (Button(&PORTA,6,1,0))     // RB6 generates Tone2
  Tone2();

  if (Button(&PORTA,7,1,0))     // RA7 generates melody 2
  {
   Melody2();
   Delay_ms(1500);              // Delay 1,5s
   Melody2();
   Delay_ms(1500);              // Delay 1,5s
   Melody2();
   }
  }
}