TMS320F28379D: DSP based SPWM for three phase inverter

Part Number: TMS320F28379D

Tool/software:

 I'm attempting to debug this code on CCS, but the debugger is not progressing past the "int main(void)" line. How can I resolve this issue?

/*
* pwm.c
*
* Created on: 23 May 2024
* Author: QUDUS
*/
#include "F28x_Project.h"
#include <math.h> // Include math.h for sinf and M_PI
#include "F2837xD_epwm.h"
#include "F2837xD_pievect.h"
#include "F2837xD_gpio.h"

#define PWM_PERIOD 10000 // For 10 kHz carrier frequency with 100 MHz SYSCLK
#define SINE_TABLE_SIZE 256
#define PHASE_SHIFT (SINE_TABLE_SIZE / 3) // 120 degrees phase shift
#define SINE_UPDATE_INTERVAL 78 // 78.125 microseconds for 50 Hz fundamental frequency

// Sine wave lookup table
float sine_table[SINE_TABLE_SIZE];

// Function prototypes
void InitEPwm1();
void InitEPwm2();
void InitEPwm3();
void InitSineTable();

int main(void)
{
InitSysCtrl(); // Initialize system control
DINT; // Disable CPU interrupts
InitPieCtrl(); // Initialize the PIE control registers
IER = 0x0000; // Disable CPU interrupts and clear all CPU interrupt flags
IFR = 0x0000; // Clear all CPU interrupt flags
InitPieVectTable(); // Initialize the PIE vector table

InitGpio(); // Initialize GPIO for ePWM

InitSineTable(); // Initialize the sine table

InitEPwm1(); // Initialize ePWM1
InitEPwm2(); // Initialize ePWM2
InitEPwm3(); // Initialize ePWM3

while(1)
{
int i;
for(i = 0; i < SINE_TABLE_SIZE; i++)
{
// Update ePWM1
EPwm1Regs.CMPA.bit.CMPA = (PWM_PERIOD / 2) * (sine_table[i] + 1);

// Update ePWM2 (phase-shifted by 120 degrees)
int idx2 = (i + PHASE_SHIFT) % SINE_TABLE_SIZE;
EPwm2Regs.CMPA.bit.CMPA = (PWM_PERIOD / 2) * (sine_table[idx2] + 1);

// Update ePWM3 (phase-shifted by 240 degrees)
int idx3 = (i + 2 * PHASE_SHIFT) % SINE_TABLE_SIZE;
EPwm3Regs.CMPA.bit.CMPA = (PWM_PERIOD / 2) * (sine_table[idx3] + 1);

DELAY_US(SINE_UPDATE_INTERVAL); // Delay to achieve the 50 Hz fundamental frequency
}
}
}

void InitEPwm1()
{
EALLOW;

// Set up ePWM1
EPwm1Regs.TBPRD = PWM_PERIOD - 1; // Set the PWM period
EPwm1Regs.TBPHS.all = 0x00000000; // Phase is 0
EPwm1Regs.TBCTR = 0x0000; // Clear counter

// Set up compare values
EPwm1Regs.CMPA.bit.CMPA = 0; // Set the initial compare A value

// Set up the counter mode
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; // Count up and down
EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE; // Disable phase loading
EPwm1Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1; // Clock ratio to SYSCLKOUT
EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV1;

// Set up the action qualifier
EPwm1Regs.AQCTLA.bit.CAU = AQ_SET; // Set PWM1A on event A, up count
EPwm1Regs.AQCTLA.bit.CAD = AQ_CLEAR; // Clear PWM1A on event A, down count

EDIS;
}

void InitEPwm2()
{
EALLOW;

// Set up ePWM2
EPwm2Regs.TBPRD = PWM_PERIOD - 1; // Set the PWM period
EPwm2Regs.TBPHS.all = PWM_PERIOD / 3; // Phase shift for 120 degrees
EPwm2Regs.TBCTR = 0x0000; // Clear counter

// Set up compare values
EPwm2Regs.CMPA.bit.CMPA = 0; // Set the initial compare A value

// Set up the counter mode
EPwm2Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; // Count up and down
EPwm2Regs.TBCTL.bit.PHSEN = TB_ENABLE; // Enable phase loading
EPwm2Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Synchronize with ePWM1
EPwm2Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1; // Clock ratio to SYSCLKOUT
EPwm2Regs.TBCTL.bit.CLKDIV = TB_DIV1;

// Set up the action qualifier
EPwm2Regs.AQCTLA.bit.CAU = AQ_SET; // Set PWM2A on event A, up count
EPwm2Regs.AQCTLA.bit.CAD = AQ_CLEAR; // Clear PWM2A on event A, down count

EDIS;
}

void InitEPwm3()
{
EALLOW;

// Set up ePWM3
EPwm3Regs.TBPRD = PWM_PERIOD - 1; // Set the PWM period
EPwm3Regs.TBPHS.all = (2 * PWM_PERIOD) / 3; // Phase shift for 240 degrees
EPwm3Regs.TBCTR = 0x0000; // Clear counter

// Set up compare values
EPwm3Regs.CMPA.bit.CMPA = 0; // Set the initial compare A value

// Set up the counter mode
EPwm3Regs.TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; // Count up and down
EPwm3Regs.TBCTL.bit.PHSEN = TB_ENABLE; // Enable phase loading
EPwm3Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Synchronize with ePWM1
EPwm3Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1; // Clock ratio to SYSCLKOUT
EPwm3Regs.TBCTL.bit.CLKDIV = TB_DIV1;

// Set up the action qualifier
EPwm3Regs.AQCTLA.bit.CAU = AQ_SET; // Set PWM3A on event A, up count
EPwm3Regs.AQCTLA.bit.CAD = AQ_CLEAR; // Clear PWM3A on event A, down count

EDIS;
}

void InitSineTable()
{
int i;
for(i = 0; i < SINE_TABLE_SIZE; i++)
{
sine_table[i] = sinf((2 * M_PI * i) / SINE_TABLE_SIZE);
}
}

Hello,

Combined your two threads as they are related.

Qudus Ayinde Aromose said:

the debugger is not progressing past the "int main(void)" line

Which line of code within the main() are you seeing the program stop at? Please using the "step over" and "step into" buttons to step into the functions so we can determine which line is specifically causing some issue. Have you been referencing any of our C2000ware software examples? If yes, which?

For SPWM guidance, please refer to these similar threads (there are likely many more that you can sift through in the E2E forum). While they reference different devices, the implementation would be analogous for F28379D:

• https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/595264/tms320f28069m-spwm-generation-implementation 
• https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/553678/spwm-problem 
• I have also seen other threads where MATLAB Simulink blocksets are used, though you would have to reach out to Mathworks directly if you need support on that: https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/946864/tms320f28379d-epwm-pulses-disappears 

Best Regards,

Allison