TMS320F28384S: Missing pulse with phase shift

Part Number: TMS320F28384S

Tool/software:

Hi,

I'm running a converter with a phase shift between ePWM1 and ePWM4, each having a 0.5 duty cycle using up-down count. The phase is changing from 0 to 180 degrees.

However, I encountered an issue of missing pulses on ePWM3 at specific phases.

To resolve this issue, I've attempted to implement T1/T2 events on ePWM3, but I couldn't find out how to properly use T1/T2 events.

I would appreciate any advice.

Here is my code:

void updatePhase(int16 ch, float32 phase)
{
    while(phase > 360.0) phase -= 360.0;
    while(phase < 0.0) phase += 360.0;

    if(phase > 180.0) {
        phase -= 360.0;
    }

    if(phase == 0.0)  {
        ePWM_Regs[ch]->TBPHS.bit.TBPHS = 0;
    }
    else if(phase > 0.0){
        ePWM_Regs[ch]->TBCTL.bit.PHSDIR = 0; 
        ePWM_Regs[ch]->TBPHS.bit.TBPHS = (int16)((float32)ePWM_Regs[ch]->TBPRD * phase * 0.00555555); // 0.00277778 = 1/360
    }
    else{ // phase < 0.0
        ePWM_Regs[ch]->TBCTL.bit.PHSDIR = 1; 
        ePWM_Regs[ch]->TBPHS.bit.TBPHS = (int16)((float32)ePWM_Regs[ch]->TBPRD * -phase * 0.00555555); // 0.00277778 = 1/360
    }

}

void updateDuty_Sym(Uint16 ch, float32 duty)
{
    ePWM_Regs[ch]->CMPA.bit.CMPA = (Uint32)((float32)ePWM_Regs[ch]->TBPRD * duty);
    ePWM_Regs[ch]->CMPB.bit.CMPB = (Uint32)((float32)ePWM_Regs[ch]->TBPRD * (1-duty));
}

void conf_ePWM_Sym(Uint16 ch, float32 freq)
{
    // Set actions
    ePWM_Regs[ch]->AQCTLA.bit.CAD = AQ_SET;
    ePWM_Regs[ch]->AQCTLA.bit.CAU = AQ_CLEAR;
    ePWM_Regs[ch]->AQCTLB.bit.CBD = AQ_SET;
    ePWM_Regs[ch]->AQCTLB.bit.CBU = AQ_CLEAR;

    if(ch==4){
        ePWM_Regs[ch]->TBCTL.bit.PHSEN = TB_DISABLE;
        ePWM_Regs[ch]->EPWMSYNCOUTEN.bit.ZEROEN = 0x1;
        ePWM_Regs[ch]->TBCTL.bit.SYNCOSEL = 0x1;    //TB_CTR_ZERO;

        ePWM_Regs[ch]->TBPHS.bit.TBPHS = 0;

    }
    else if(ch!=4) {
        ePWM_Regs[ch]->TBCTL.bit.PHSEN = TB_ENABLE;
        ePWM_Regs[ch]->EPWMSYNCINSEL.bit.SEL = 0x4;
        ePWM_Regs[ch]->TBCTL.bit.SYNCOSEL = 0x1;    //TB_SYNC_IN;

    }

    SyncSocRegs.SYNCSELECT.bit.SYNCOUT = 0x1;

    // Setup TBCLK
    ePWM_Regs[ch]->TBCTL.bit.CTRMODE = TB_COUNT_UPDOWN; // Count up-down
    ePWM_Regs[ch]->TBCTL.bit.PRDLD = TB_SHADOW;
    ePWM_Regs[ch]->TBCTL.bit.HSPCLKDIV = TB_DIV1;

    ePWM_Regs[ch]->CMPCTL.bit.SHDWAMODE = CC_SHADOW;    // Load registers every ZERO
    ePWM_Regs[ch]->CMPCTL.bit.SHDWBMODE = CC_SHADOW;
    ePWM_Regs[ch]->CMPCTL.bit.LOADAMODE = CC_CTR_ZERO;
    ePWM_Regs[ch]->CMPCTL.bit.LOADBMODE = CC_CTR_ZERO;

    ePWM_Regs[ch]->DBCTL.bit.IN_MODE = DBA_RED_DBB_FED;
    ePWM_Regs[ch]->DBCTL.bit.POLSEL = DB_ACTV_HIC;
    ePWM_Regs[ch]->DBCTL.bit.OUT_MODE = DB_FULL_ENABLE;    //deadtime

    updateDuty_Sym(ch, 0.0);
    updatePhase(ch, 0.0);
    updateFreq(ch, freq);
    updateDeadtime(ch, 0.0);
}