TMS320F28377S: Issue linking ePWM10 and ePWM11 using EPWMXLINK

Hi Jens,

Can you post all of your EPWM configuration code?

For test purposes, have you tried linking EPWM10 to any PWM that's not 11? And EPWM11 with any PWM other than 10? We have not heard of any issues along these lines, so I suspect it's a configuration issue somewhere.

Regards,
Kris

Hi Kris,

thanks for your reply. I haven't tried linking ePWM11 to any other module except 10. It's probably something I should do just to see what happens. In the meantime here is my configuration code:

#define     EPWM1_LINK      0x00
#define     EPWM2_LINK      0x01
#define     EPWM3_LINK      0x02
#define     EPWM4_LINK      0x03
#define     EPWM5_LINK      0x04
#define     EPWM6_LINK      0x05
#define     EPWM7_LINK      0x06
#define     EPWM8_LINK      0x07
#define     EPWM9_LINK      0x08
#define     EPWM10_LINK     0x09
#define     EPWM11_LINK     0x0A
#define     EPWM12_LINK     0x0B

void    pwmInitModules(void)
{
    EALLOW;
    CpuSysRegs.PCLKCR0.bit.TBCLKSYNC = 0;
    EDIS;

    /* all PWM modules use the same init routine, with a few parameters */
    _pwmInitModuleX(&EPwm1Regs, EPWM_PHASE_0DEG, EPWM1_LINK);
    _pwmInitModuleX(&EPwm2Regs, EPWM_PHASE_180DEG, EPWM1_LINK);

    _pwmInitModuleX(&EPwm3Regs, EPWM_PHASE_0DEG, EPWM3_LINK);
    _pwmInitModuleX(&EPwm4Regs, EPWM_PHASE_180DEG, EPWM3_LINK);

    _pwmInitModuleX(&EPwm6Regs, EPWM_PHASE_0DEG, EPWM6_LINK);
    _pwmInitModuleX(&EPwm7Regs, EPWM_PHASE_180DEG, EPWM6_LINK);

    _pwmInitModuleX(&EPwm8Regs, EPWM_PHASE_0DEG, EPWM8_LINK);
    _pwmInitModuleX(&EPwm9Regs, EPWM_PHASE_180DEG, EPWM8_LINK);

    _pwmInitModuleX(&EPwm10Regs, EPWM_PHASE_0DEG, EPWM10_LINK);
    _pwmInitModuleX(&EPwm11Regs, EPWM_PHASE_180DEG, EPWM10_LINK);

    EPwm2Regs.ETSEL.bit.INTEN = 1;                  // Enable INT for EPWM2

    EALLOW;
    /* This starts all configured PWM clocks at once */
    CpuSysRegs.PCLKCR0.bit.TBCLKSYNC = 1;
    EDIS;
}

/** @brief Configures function for EPWM modules.
 *
 *  This function is used to configure EPWM modules 1-11. These PWM modules use
 *  the exact same configuration except for very few parameters.
 *  PWM modules with uneven numbers don't have a phase shift, PWM modules with even numbers
 *  have a phase shift of 180° compared to PWM with uneven numbers.
 *  Some PWM modules can be linked to others. Linking PWM modules means that all configuration
 *  data written to one module during run time will automatically be written to the all linked
 *  modules. In conjunction with the 180° phase shift and complementary PWM outputs this
 *  mechanism is used to control a full 4 PWM H Bridge.
 *
 *  @param EPWM_REGS* pwm_regs - pointer to module specific configuration structure
 *  @param Uint16 phaseShift - phase shift in degrees compared to linked module
 *  @param Uint16 linkPwm - PWM module to link
 *  @retval void
 */
static void     _pwmInitModuleX(volatile struct EPWM_REGS* pwm_regs, Uint16 phaseShift, Uint16 linkPwm)
{
    // Setup TBCLK
    pwm_regs->TBCTL.bit.CTRMODE     = TB_COUNT_UP;                  // Count up
    pwm_regs->TBPRD                 = EPWM_TIMER_TBPRD - 1;         // Set timer period

    pwm_regs->TBCTR                 = 0x0000;                       // Clear counter
    pwm_regs->TBCTL.bit.HSPCLKDIV   = TB_DIV1;                      // Clock divider to SYSCLKOUT for pwm clock for high resolution
    pwm_regs->TBCTL.bit.CLKDIV      = TB_DIV1;                      // Clock divider to SYSCLKOUT for pwm clock

    // Setup shadow register load on ZERO
    pwm_regs->CMPCTL.bit.SHDWAMODE  = CC_SHADOW;
    pwm_regs->CMPCTL.bit.SHDWBMODE  = CC_SHADOW;
    pwm_regs->CMPCTL.bit.LOADAMODE  = CC_CTR_ZERO;
    pwm_regs->CMPCTL.bit.LOADBMODE  = CC_CTR_ZERO;

    // Set Compare values
    pwm_regs->CMPA.bit.CMPA         = EPWM_INITIAL_CMP;             // Set compare A value

    pwm_regs->AQCTL.bit.SHDWAQAMODE = 1;                            // Use shadow registers for action qualifiers EPWMA
    pwm_regs->AQCTL.bit.SHDWAQBMODE = 1;                            // Use shadow registers for action qualifiers EPWMB

    pwm_regs->AQCTL.bit.LDAQAMODE   = 1;
    pwm_regs->AQCTL.bit.LDAQBMODE   = 1;

    // Set actions
    if (phaseShift == EPWM_PHASE_0DEG )
    {

        pwm_regs->TBCTL.bit.PHSEN       = TB_DISABLE;               // Disable phase loading
        pwm_regs->TBCTL.bit.SYNCOSEL    = TB_SYNC_IN;               // Just forward any received SYNC signals

        /* Initial configuration after startup is to disable PWM
         * output until a treatment begins.
         *
         * Disable TOP1 leg - cutting off from power supply */
        pwm_regs->AQCTLA.bit.PRD        = AQ_CLEAR;
        pwm_regs->AQCTLA.bit.CAU        = AQ_CLEAR;

        /* Enable BOT1 leg - transformers to GND */
        pwm_regs->AQCTLB.bit.PRD        = AQ_SET;
        pwm_regs->AQCTLB.bit.CAU        = AQ_SET;
    }
    else
    {
        pwm_regs->TBCTL.bit.PHSEN       = TB_ENABLE;                // Enable phase loading
        pwm_regs->TBCTL.bit.SYNCOSEL    = TB_SYNC_DISABLE;          // Don't generate SYNC signals on phase shifted EPWM modules
        pwm_regs->TBPHS.bit.TBPHS       = phaseShift;

        /* Initial configuration after startup is to disable PWM
         * output until a treatment begins.
         *
         * Disable TOP1 leg - cutting off from power supply */
        pwm_regs->AQCTLA.bit.PRD        = AQ_CLEAR;
        pwm_regs->AQCTLA.bit.CAU        = AQ_CLEAR;

        /* Enable BOT1 leg - transformers to GND */
        pwm_regs->AQCTLB.bit.PRD        = AQ_SET;
        pwm_regs->AQCTLB.bit.CAU        = AQ_SET;
    }

    // Active Low complementary PWMs - setup the dead band
    pwm_regs->DBCTL.bit.OUT_MODE    = DB_FULL_ENABLE;
    pwm_regs->DBCTL.bit.POLSEL      = DB_ACTV_HIC;
    pwm_regs->DBCTL.bit.IN_MODE     = DBA_ALL;
    pwm_regs->DBRED.bit.DBRED       = EPWM_DBRED;
    pwm_regs->DBFED.bit.DBFED       = EPWM_DBFED;

    // Interrupt where we will change the Compare Values
    pwm_regs->ETSEL.bit.INTSEL      = ET_CTR_ZERO;              // Select INT on Zero event
    pwm_regs->ETSEL.bit.INTEN       = 0;                        // Disable INT

    pwm_regs->ETPS.bit.INTPSSEL     = 1;
    pwm_regs->ETINTPS.bit.INTPRD2   = PWM_EVENT_RATE;

    pwm_regs->EPWMXLINK.bit.CMPALINK    = linkPwm;

}