Hi,
I am trying to generate 4 SPWM signals (reference signal 50Hz, Triangular wave 2.5kHz) for my h-bridge inverter like the following:
However, its not giving appropriate output for the complementary signals. Below is my code. I will be grateful if someone can help. Thanks in advance.
#include <msp430g2553.h>
#define pwmPeriod 400 // carrier of 2.5kHz and reference of 50Hz. PWM period is 0.4 ms.
const unsigned int phalfcycle[25] = {200, 223, 245, 266, 287, 306, 323, 339, 352, 363, 371, 377, 380, 380, 377, 371, 363, 352, 339, 323, 306, 287, 266, 245, 223};
unsigned int pulsecounterA0 = 0;
unsigned int pulsecounterA1 = 0;
void main(void)
{
WDTCTL = WDTPW + WDTHOLD; // Stop WDT
//Calibrate DCO for 1MHz operation
BCSCTL1 = CALBC1_1MHZ;
DCOCTL = CALDCO_1MHZ;
P1OUT &= 0x00; // Setting all pins as low
P2OUT &= 0x00;
P1DIR |= BIT2 + BIT6; // PWM Outputs
P2DIR |= BIT1 + BIT2;
P1SEL |= BIT2;
P2SEL |= BIT1;
TACCR0 = pwmPeriod - 1; // setting PWM period to 0.4 ms, 400-1 clock ticks of SMCLK
TA1CCR0 = pwmPeriod - 1;
TACCTL0 = CCIE; // Enable Timer A0 Interrupt for CCR0
TA1CCTL0 = CCIE;
TACCTL1 = OUTMOD_2; // RESET/SET for Timer A0 CCR1
TA1CCTL1 = OUTMOD_6;
TACTL = TASSEL_2 + MC_1 + TACLR; // Timer_A0 control register with SMCLK = 1 MHz, Upmode. Starting the timer
TA1CTL = TASSEL_2 + MC_1 + TACLR;
_BIS_SR(LPM0_bits + GIE); // Enter LPM0 w/ interrupt
}
// Timer A0 interrupt service routine
// #pragma is a catch-all preprocessor directive that is used to extend the functionality of the compiler that is not already covered by predefined directives.
//In this code, the compiler (and the linker) is being told that we are going to create an ISR for TIMER0_A0_VECTOR.
#pragma vector=TIMER0_A0_VECTOR
__interrupt void Timer_A0 (void)
{
//TACCTL1 = OUTMOD_7;
if (pulsecounterA0 < 25)
{
TACCR1 = phalfcycle[pulsecounterA0];
pulsecounterA0 = pulsecounterA0 + 1;
}
else
{
P1SEL ^= (BIT2 + BIT6);
pulsecounterA0 = 0;
}
}
// Timer A1 interrupt service routine
// #pragma is a catch-all preprocessor directive that is used to extend the functionality of the compiler that is not already covered by predefined directives.
//In this code, the compiler (and the linker) is being told that we are going to create an ISR for TIMER1_A0_VECTOR.
#pragma vector=TIMER1_A0_VECTOR
__interrupt void Timer_A1 (void)
{
if (pulsecounterA1 < 25)
{
TA1CCR1 = phalfcycle[pulsecounterA1];
pulsecounterA1 = pulsecounterA1 + 1;
}
else
{
P2SEL ^= (BIT1 + BIT2);
pulsecounterA1 = 0;
}
}
