[PIC] Siren Sound Using Pwm signal

Code C - [expand]
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#include <htc.h>
#include <stdio.h>
#include<pic.h>
#include<stdint.h>
#define _XTAL_FREQ 20000000
unsigned int i=0; 
#define TMR2PRESCALE 16
long freq;
unsigned int x;
#define LED RC7
#define LED1 RC6
#define LED2 RC2
unsigned short int cnt, num,Dgt=0;
unsigned int i;
unsigned int j;
 
void out_p(int l , int k);
int PWM_Max_Duty()
{
 return(_XTAL_FREQ/(freq*TMR2PRESCALE);
}
PWM1_Init(long fre)
{
 PR2 = (_XTAL_FREQ/(freq*4*TMR2PRESCALE)) - 1;
 freq = fre;
}
 
PWM1_Duty(unsigned int duty)
{
 if(duty<1024)
 { 
 duty = ((float)duty/1023)*PWM_Max_Duty();
 CCP1X = duty & 2;
 CCP1Y = duty & 1;
 CCPR1L = duty>>2;
 }
}
 
PWM1_Start()
{
 CCP1M3 = 1;
 CCP1M2 = 1;
 #if TMR2PRESCALE == 1
 T2CKPS0 = 0;
 T2CKPS1 = 0;
 #elif TMR2PRESCALE == 4
 T2CKPS0 = 1;
 T2CKPS1 = 0;
 #elif TMR2PRESCALE == 16
 T2CKPS0 = 1;
 T2CKPS1 = 1;
 #endif
 TMR2ON = 1;
 TRISC2 = 0;
}
 
PWM1_Stop()
{
 CCP1M3 = 0;
 CCP1M2 = 0;
}
 
 
void SetPWMDutyCycle(unsigned int DutyCycle) // Give a value in between 0 and 1024 for DutyCycle
{
 CCPR1L = DutyCycle>>2; // Put MSB 8 bits in CCPR1L
 CCP1CON &= 0xCF; // Make bit4 and 5 zero
 CCP1CON |= (0x30&(DutyCycle<<4)); // Assign Last 2 LSBs to CCP1CON
}
 
 
void InitPWM(void)
{
 TRISC2 = 0; // Make CCP1 pin as output
 CCP1CON = 0x0C; // Configure CCP1 module in PWM mode
PR2 = 0xFF; // Configure the Timer2 period
 T2CON = 0x01; // Set Prescaler to be 4, hence PWM frequency is set to 4.88KHz.
SetPWMDutyCycle(0); // Intialize the PWM to 0 duty cycle
T2CON |= 0x04; // Enable the Timer2, hence enable the PWM.
}
 
 
void Delay(int k)
{
for(j=0;j<k;j++);
}
void tone(int Frequency,int duration)
{
 SetPWMDutyCycle(Frequency);
 Delay(duration);
 
}
 
 
void Timer1_Interrupt()
 {
 
 INTCON = 0b00000000;
 PIE1=0b00000001;
 PIR1=0x01;
 TMR1H=0x0B;
 TMR1L=0xDC; 
 T1CON=0x31;
 // T1CON=0x01;
 }
 
 
 
 void Init_Controller()
 {
 cnt=100; 
 TRISC=0b00000000; 
 PORTC=0b00000000;
 TRISB=0b10000000;
 PORTB = 0b00000000;
 TRISA=0b00000000; 
 PORTA=0X00; 
 ADCON0 = 0b00000000;
 ANSEL = 0b00000000;
 Timer1_Interrupt();
 LED=0;
 LED1=0;
 LED2=0;
 
 }
 
 
void interrupt isr(void)
 {
 if(TMR1IF==1)
 {
 TMR1H=0xEA; // Load the time value(0x0BDC) for 100ms delay
 TMR1L=0x60; //Timer1 Interrupt for 65000
 TMR1IF=0; // Clear timer interrupt flag
 Dgt++;
 
 LED=!LED;
 LED1=!LED1;
 
 
 } 
 
 }
 
void main(void)
 {
Init_Controller();
 Timer1_Interrupt();
 GIE=1;
 PEIE=1;
 TMR1IE=1;
PWM1_Init(5000);
PWM1_Start();
 
while(1)
 {
 
 PWM1_Duty(500);
 
 }
 
}