CCS/TMS320F28069: Program does not run when I update PWM1

Just wanted to add, I am using Code Composer Version: 7.4.0.00015 and compiler version TI v18.9.0.ST.

Best Regards.

Cristina,

     Thanks for explaining your issue well and providing some initial debug!

• Where are you updating your CMPA values in your code? The best place to do this will be in your PWM ISR.
  • Secondly, if you are updating the PWM in the ISR, how is your ISR configured?
• When you say the program does not run, what happens?

We will have to debug this a bit more...

1. Does the code load onto the device?
2. How is the device failing? ...does it halt, does it execute the wrong code, does the PWM output anything?
3. Have you verified your configurations using the memory browser?
4. Are you using EALLOW before writing to EALLOW protected registers?

Regards,
Cody

Hi, thanks for the answer.

I use ePWM1 to generate a periodic ADC SOC - ADCINT1, so I update the CMPA value at the end of the ADC interrupt, just before clearing the flag. I do this because later I will need to read some sensor through the ADC. This is the ADC configuration: 

AdcRegs.ADCCTL2.bit.ADCNONOVERLAP = 1;	       // Enable non-overlap mode
AdcRegs.ADCCTL1.bit.INTPULSEPOS	= 1;	               // ADCINT1 trips after AdcResults latch

AdcRegs.INTSEL1N2.bit.INT1E     = 1;	                       // Enabled ADCINT1
AdcRegs.INTSEL1N2.bit.INT1CONT  = 0;	               // Disable ADCINT1 Continuous mode
AdcRegs.INTSEL1N2.bit.INT1SEL 	= 1;                 // setup EOC1 to trigger ADCINT1 to fire

AdcRegs.ADCCTL1.bit.ADCREFSEL = 0;                    //Select internal reference mode
AdcRegs.ADCCTL1.bit.VREFLOCONV = 1;                 //Select VREFLO internal connection on B5

This is how I know it is not running: Whenever I run a CCS program I put some expressions to watch and enable continuous refresh, so I know the program is running just visually because I see yellow updates. Also, I have one LED in the PCB that is just turned on dummy in the main and is not doing so. Lastly, I check with the oscilloscope and I don't have any PWM output. 

Regarding the rest of the questions:

1. I am not sure how to check if it is really loading onto the device.

2. I already answered this above.

3. Again, I am not sure how to verify the configurations using the memory browser.

4. I have some initialization functions and just to be sure I write EALLOW at the beginning of each one. I belive CMPA is not protected, but just in case I tried writing EALLOW before updating and nothing changed.

Best regards.

Cristina,

take a look at the following help document, it should guide you on how you can use the tools (breakpoints, single stepping, and the memory browser) to help find out where the problem is.

Regards,
Cody 

Thanks for the information,

I didn't think of using the breakpoints because I assumed the program was not even loading, but that is not correct. Now I am even more confused than before.

I added a break point in the main, just before the while(1){}. I turn a LED on just before this loop and is turning on. Sadly, if after that I go step by step the pointer gets stack in the while(1) and no matter how many times I press step into it doesn't move. Step over does not work also. It is like the interruption is not taking place, but it does not make sense since the only thing that changes between two codes is what value I try to add to CMPA, and that is something that happens after some lines of code in the interruption.

Regards,

Cristina.

Cristina,
set a breakpoint in each of the interrupts, then run the code. If it executes the interrupt it should halt the program counter.

Then run it again and see if it ever enters the interrupt again. If it does not enter the interrupt again you may want to check if you correctly have acknowledged the interrupts.

Regards,
Cody

Hi,

There is only one interrupt in my program, the ADC one. I set a breakpoint there and it is getting inside the interruption 5 times. Then it stops entering. This is how I acknowledged the interruptions:

       // Reinitialize for next ADC sequence

       AdcRegs.ADCINTFLGCLR.bit.ADCINT1 = 1;           //Clear ADCINT1 flag reinitialize for next SOC

       PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;         // Acknowledge interrupt to PIE

 

I have the problem isolated in the update of the CMPA register for PWM1, and no matter how much I simplify the code it won't do it correctly.

Is there a possibility of a bug somehow? Because I tried also this in the interruption:

pwm_aux = EPwm1Regs.TBPRD;

aux1 = pwm_aux * Du;

aux2 = aux1;

EPwm1Regs.CMPA.half.CMPA = aux2;

And defined as global variables:

float Du = 0.0;

unsigned int pwm_aux = 0;

float aux1 = 0.0;

unsigned int aux2 = 0.0;

  

Well, if I define aux2 as unsigned int the code does not run more than those 5 times. When I define aux2 as int it runs "forever", but obviously the result is not correct because of the sign.

Thanks for the effort on trying to help me.