CCS/TMS320F28027: ECAP interrupt and EPWM interrupt do not work at same time.

Tool/software: Code Composer Studio

Dear all,

I wish to use ECAP interrupt to capture several pulse, and then change the duty cycle of PWM signal from EPWM ports. The PWM function is same as the example "Example_2802xEPwmUpDownAQ" which has about 3 interrupt already. I can use a external interrupt from keys to change the duty cycle of the PWM signal very well. However, after I add the ECAP interrupt into my program, the interrupt has never happened. I still can use the keys to change the PWM signal, but the ECAP function did not work. I learned the ECAP function from example "Example_2802xECap_Capture_Pwm". The example has only 1 interrupt, but my program has 4. The program is used to change the period of the PWM signal, but my program is used for duty cycle.

I tried to change the priority of the interrupts as the example "Example_2802xSWPrioritizedInterrupts". The problems have not really gone away.

Can some one help me please.

#define ISRS_GROUP3  (M_INT1|M_INT2|M_INT3|M_INT4)
#define ISRS_GROUP4  (M_INT1|M_INT3|M_INT4)  

   IER = 0x0000;
   IFR &= 0x0000;

// Initialize the PIE vector table with pointers to the shell Interrupt
// Service Routines (ISR).
// This will populate the entire table, even if the interrupt
// is not used in this example.  This is useful for debug purposes.
// The shell ISR routines are found in f2802x_DefaultIsr.c.
// This function is found in f2802x_PieVect.c.
   InitPieVectTable();

// Interrupts that are used in this example are re-mapped to
// ISR functions found within this file.
   EALLOW;  // This is needed to write to EALLOW protected registers
   PieVectTable.EPWM1_INT = &epwm1_isr;
   PieVectTable.EPWM2_INT = &epwm2_isr;
   PieVectTable.EPWM3_INT = &epwm3_isr;
   PieVectTable.ECAP1_INT = &ecap1_isr;
   EDIS;    // This is needed to disable write to EALLOW protected registers



// Step 4. Initialize all the Device Peripherals:
// This function is found in f2802x_InitPeripherals.c
// InitPeripherals();  // Not required for this example

// For this example, only initialize the ePWM

   EALLOW;
   SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 0;
   EDIS;

   InitEPwm1Example();
   InitEPwm2Example();
   InitEPwm3Example();
   InitECapture();
   EALLOW;
   SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1;
   EDIS;

// Step 5. User specific code, enable interrupts:


// Copy time critical code and Flash setup code to RAM
// This includes the following ISR functions: EPwm1_timer_isr(), EPwm2_timer_isr()
// EPwm3_timer_isr and and InitFlash();
// The  RamfuncsLoadStart, RamfuncsLoadEnd, and RamfuncsRunStart
// symbols are created by the linker.
   memcpy(&RamfuncsRunStart, &RamfuncsLoadStart, (size_t)&RamfuncsLoadSize);

// Call Flash Initialization to setup flash waitstates
// This function must reside in RAM
   InitFlash();


// Enable CPU INT3 which is connected to EPWM1-3 INT:


   ECap1IntCount = 0;
   ECap1PassCount = 0;

   PieCtrlRegs.PIECTRL.bit.ENPIE = 1;

   PieCtrlRegs.PIEIER3.bit.INTx1 = 1;
   PieCtrlRegs.PIEIER3.bit.INTx2 = 1;
   PieCtrlRegs.PIEIER3.bit.INTx3 = 1;
   PieCtrlRegs.PIEIER4.bit.INTx1 = 1;

//   PieCtrlRegs.PIEIER3.all = 0x00FF;
//   PieCtrlRegs.PIEIER4.all = 0x00FF;

   PieCtrlRegs.PIEACK.all = (M_INT3|M_INT4);

   IER |= (M_INT3|M_INT4);

//   PieCtrlRegs.PIEIFR3.all = ISRS_GROUP3;
//   PieCtrlRegs.PIEIFR4.all = ISRS_GROUP4;

// Enable global Interrupts and higher priority real-time debug events:
   EINT;   // Enable Global interrupt INTM
   ERTM;   // Enable Global realtime interrupt DBGM

ECAP function:

void InitECapture()
{
   ECap1Regs.ECEINT.all = 0x0000;             // Disable all capture interrupts
   ECap1Regs.ECCLR.all = 0xFFFF;              // Clear all CAP interrupt flags
   ECap1Regs.ECCTL1.bit.CAPLDEN = 0;          // Disable CAP1-CAP4 register loads
   ECap1Regs.ECCTL2.bit.TSCTRSTOP = 0;        // Make sure the counter is stopped

   // Configure peripheral registers
   ECap1Regs.ECCTL2.bit.CONT_ONESHT = 1;      // One-shot
   ECap1Regs.ECCTL2.bit.STOP_WRAP = 3;        // Stop at 4 events
   ECap1Regs.ECCTL1.bit.CAP1POL = 1;          // Falling edge
   ECap1Regs.ECCTL1.bit.CAP2POL = 0;          // Rising edge
   ECap1Regs.ECCTL1.bit.CAP3POL = 1;          // Falling edge
   ECap1Regs.ECCTL1.bit.CAP4POL = 0;          // Rising edge
   ECap1Regs.ECCTL1.bit.CTRRST1 = 1;          // Difference operation
   ECap1Regs.ECCTL1.bit.CTRRST2 = 1;          // Difference operation
   ECap1Regs.ECCTL1.bit.CTRRST3 = 1;          // Difference operation
   ECap1Regs.ECCTL1.bit.CTRRST4 = 1;          // Difference operation
   ECap1Regs.ECCTL2.bit.SYNCI_EN = 0;         // Enable sync in
   ECap1Regs.ECCTL2.bit.SYNCO_SEL = 0;        // Pass through
   ECap1Regs.ECCTL1.bit.CAPLDEN = 1;          // Enable capture units

   ECap1Regs.ECCTL2.bit.TSCTRSTOP = 1;        // Start Counter
   ECap1Regs.ECCTL2.bit.REARM = 1;            // arm one-shot
   ECap1Regs.ECCTL1.bit.CAPLDEN = 1;          // Enable CAP1-CAP4 register loads
   ECap1Regs.ECEINT.bit.CEVT4 = 1;            // 4 events = interrupt
}

Four interrupt:

__interrupt void epwm1_isr(void){my code}

__interrupt void epwm2_isr(void){my code}

__interrupt void epwm3_isr(void){my code}

__interrupt void ecap1_isr(void){my code}