MSP430 Sinus funkcia

#include <msp430.h>
#include <MSP430F5529.h>
#include <stdint.h>
#include <math.h>


#define Button BIT1    // Button P2.1
#define PI 3.14159


int counter = 0;
int Duty = 0;         // PWM duty cycle
int Period = 200;    // PWM period


void main(void) {
    WDTCTL = WDTPW | WDTHOLD;   // stop watchdog timer

    P1DIR |= BIT2;              // Set P1.2 as output pin
    P1SEL |= BIT2;              // Enable special function of P1.2
    TA0CTL |= MC__STOP;         // Stop Timer A

    TA0CTL |= TASSEL__SMCLK;    // Set SMCLK as timer clock source
    TA0CTL |= ID_0;             // Set clock divider to 1
    TA0CTL |= TACLR;            // Clear timer counter

    TA0CTL |= TACLR;            // Clear timer counter
    TA0CCTL1 |= CCIE;           // Enable interrupt for compare register 1
    TA0CCTL1 |= OUTMOD_6;       // Set PWM output mode
    TA0CCR0 = Period;           // Set PWM period
    TA0CCR1 = Duty;             // Set initial PWM duty cycle
    TA0CTL |= MC__UP;           // Start timer in UP mode
    __bis_SR_register(GIE);     // Global interrupt enable

    // Configure button P2.1 for interrupt
    P2REN |= Button;            // Enable pull-up resistor for button
    P2IE |= Button;             // Enable interrupt for button
    P2IES |= Button;            // Set interrupt on falling edge

    while(1) {

    }
}

#pragma vector=TIMER0_A1_VECTOR
__interrupt void Timer_A(void) {
    counter++;                 // Increase counter for each PWM cycle
    double freq = sin(counter*2*PI/Period) + 1.0/5.0*sin(5*counter*2*PI/Period) + 1.0/9.0*sin(9*counter*2*PI/Period);
    int duty = (int) (freq*Period/2.0);     // Calculate duty cycle from frequency
    if(duty < 0) duty = 0;                  // Limit duty cycle to positive values
    if(duty > Period) duty = Period;        // Limit duty cycle to maximum period
    TA0CCR1 = duty;                         // Set new duty cycle
    TA0CTL &= ~TAIFG;                       // Clear timer interrupt flag
}


/*
#pragma vector=PORT2_VECTOR
__interrupt void Port_2(void) {
    P2IE &= ~Button;                         // Disable interrupt for button
    P2IFG &= ~Button;                        // Clear button interrupt flag
    if(P2IES & Button)                       // Rising edge
    {
        counter = 0;                         // Reset counter to start frequency equation from the beginning
        TA0CTL |= MC__STOP;                  // Stop timer
        TA0CCR1 = 0;                         // Set duty cycle to 0
        P2IES &= ~Button;                    // Set interrupt on rising edge for next time
    }
    else                                     // Falling edge
    {
        TA0CTL |= TACLR;                     // Clear timer counter
        TA0CCR1 = Duty;                      // Set initial duty cycle
        P2IES |= Button;                     // Set interrupt on falling edge for next time
    }
    P2IE |= Button;                          // Enable interrupt for button
}*/