CCS/TMS320F28335: ADC Interrupt and CPU Timer 0 interrupt does not function together

It's difficult to give general guidelines because it's very dependent on the application. It really depends on the priority and payload of each ISR. In a control application, the ADC ISR would typically be executing time critical code so you might want that to have the highest priority, and the other ISR's to be pre-empted by it. By way of example, below are a couple of ISRs set up this way on F28335.

main()
{
// device init and so on...

PieVectTable.ADCINT1 = &AdcIsr;
PieVectTable.TINT0 = &Timer0Isr;
PieCtrlRegs.PIEIER1.bit.INTx1 = 1;
PieCtrlRegs.PIEIER1.bit.INTx7 = 1;
IER |= M_INT1;
EINT;

while(1);
}

interrupt void AdcIsr(void)
{
AdcRegs.ADCTRL2.bit.RST_SEQ1 = 1; // Reset SEQ1
AdcRegs.ADCST.bit.INT_SEQ1_CLR = 1; // Clear INT SEQ1 bit
PieCtrlRegs.PIEACK.all = PIEACK_GROUP1; // Acknowledge interrupt to PIE

// read ADC data
xInput = (float) AdcResult.ADCRESULT0;
yInput = (float) AdcResult.ADCRESULT1;

// do time critical stuff here...
}

interrupt void Timer0Isr(void)
{
CpuTimer0Regs.TCR.bit.TIF = 1; // clear timer 0 interrupt flag
PieCtrlRegs.PIEACK.all = PIEACK_GROUP1; // acknowledge PIE interrupt
EINT; // allow nested interrupts

// your pre-emptible code here...

DINT; // mask global interrupts
}

This should work fine unless your ADC ISR payload is large enough to risks losing timer interrupts.

There are some code examples in C2000Ware which should help you. See the "adc_soc" example for the ADC set up and use, and "sw_prioritized_interrupts" for multiple prioritized interrupts. There are some gotchas when you multiplex peripheral interrupts (see chapter 8.3 of the System Control & Interrupts user's guide for this device for more information) so the second example may help.

Not sure if this is what you were looking for, but feel free to post back if you need anything more.

Regards,

Richard

I think it may be about my ISR payload being large, but now I am only able to get one interrupt from the CPU timer.

Yeah, changing it to the CPUtimer2 did the job. thank you so much for your help!