TMS320F28375S: Effect of AQCSFRC on PWM interrupt serving time

Hi Shreni, 

What do you mean by continuous software forcing? Have you instead looked at using the trip zone submodule? How are you generating your interrupt, are you using event trigger?

Best,

Ryan Ma

Hi Ryan,

1) Continuous software forcing in the sense I have been setting EPwmxRegs.AQCSFRC.bit.CSFA = 1 in every 125us for 10msec. I am doing this to avoid any contention that can be caused with shadow to active loading of CMP=0 at TBCTR = 0(As mentioned in TRM). While using this, I sometimes observed delay in the interrupt serving time.

Instead of above, when I set the same only at the first instant of zero crossing, I didn't observe the delay mentioned above.

2) I didn't use Tripzone submodule. I only want to forcefully turn off a switch at zero crossing to avoid the above mentioned contention.

3) Yes, I have used Event trigger. Interrrupt shall be served at every second event of TBCTR= 0

Thanks,

Shreni. P

Hi Ryan,

I found the issue is not because of AQCSFRC but it is another peripheral's interrupt that is effecting PWM interrupt serving time. Thanks for your time.

Thanks,

Shreni. P