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squalo

I can't stop PWM signal because i can't use timer interrupt vector

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Hi,

i'm trying to start a pwm signal and stop it after 50 miliseconds. But i can't because i can't use timer interrupt vector properly. my count never increments.

Here is my code 

#include <msp430.h>
#include <msp430g2553.h>
void startPWM(void);

unsigned char counter=0;

void stopPWM(void);

int main(void)
{
WDTCTL = WDTPW | WDTHOLD; // Stop watchdog timer
BCSCTL1 = CALBC1_1MHZ; // Set range
DCOCTL = CALDCO_1MHZ;
CCTL0 = CCIE;

P2DIR |= BIT2; //IR transmitter
P2SEL |= BIT2;// Select pwm pin (transmitter)

P2OUT=0x00;


while(1){

if((P1IN & BIT4)!=BIT4) //button is pressed
{
startPWM(); //send pwm
stopPWM(); // stop after 50 ms
}

}

}

void startPWM(void) // pwm signal
{
TA1CCR0 = 26-1; // Period Register
TA1CCR1 = 13; // 50% dutycycle
TA1CCTL1 |= OUTMOD_6; // TA1CCR1, Reset/Set
TA1CTL = TASSEL_1 + MC_1 + TACLR;
}


void stopPWM(void) // trying to stop after 50 ms
{
CCR0 = 5000; // CCR0 5 ms
TACTL = TASSEL_2 + MC_2; //
}

#pragma vector=TIMER0_A0_VECTOR // Timer0_A0
__interrupt void Timer_A (void)
{
if(++counter==10){ // is counter 10 (5*10=ms)
TA1CCR1 = 0; ; // Stop timer so it can't send PWM signal
counter = 0;
}
}

 

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