TMS320F28379D: How to change PWM at run time

can you give some example about how I can use JTAG and UART for this purpose ?

Thanks

Yes, I am using LAUNCHXL-TMS320F28379D | Development Kit. Can you give some example or direct me to a guide which sends the frequency, duty etc through JTAG or UART to controller where a function is triggered that changes the register values accordingly.

Hi,

WHen you said you've "generated HRPWM on the controller successfully" are you using Simulink for code generation?

Hi,

No, I am using Code Composer Studio.

Hi,

Najeeb Uddin said:

No, I am using Code Composer Studio.

Hi,

Yes, I set the frequency and duty in the control software. But every time I want to change frequency and duty I have to recompile the code and that takes a lot of time since at the later part of my project I will be testing a DC/DC boost converter, and some other stuff with the PWMs that I generated from my controller. In that testing I would have to change frequency very frequently so I cant recompile code each time I need to make a small change to frequency, duty or phase of the PWM.

That's why I am trying to figure out a way to change them at run time (on the fly).

Thanks

Hi,

Sorry - your question is still not clear to me.

What is stopping you from changing these values through debugger? Make these values as variables in your code and update through debugger.
Why do you have to recompile every time? Since you are already using CCS to run code on the Launch Pad - why do you need another interface to update these values?

Hi,

Yeah, I had tried updating register values from the watch expression window of the code composer studio and it works but setting the PWM to certain frequency lets say 10k hz, is not as simple as writing 10k in some register, the respective period has to be calculated and stored in the respective registers and in the case of HRPWM, things get even more complicated, things like mep steps has to be calculated. I derived equations for those calculation and also tried them in the code and they work fine but now I want the controller to compute those equations in the run time for provided frequencies.

Now I am speculating if there any way I could a create a function with parameters of frequency, duty etc and that function calculates the respective register values, Now if somehow I could trigger this function from my computer using code composer or JTAG or UART or anything else to set the PWM to the desired frequency in the run time.

Thanks

Hi,

Sure - You can implement the function in the C28x CPU. 
Calculations for period and duty, from frequency and duty cycle requirements, are indeed very simple.
Please refer to Figure 15-6. Time-Base Frequency and Period
Are you having any issue in implementing these equations?

The MathWorks C2000 support allows for live parameter tuning.  I'm not exactly certain if it will work for you exact use case, but might be worth a look, especially if you have access to the required MathWorks tools.

https://e2e.ti.com/support/microcontrollers/c2000/f/171/t/484814

Cheers,

-Brian

Yes, this might work but I am working with code composer for my project and can't switch to matlab now. Thanks for the response.

Thanks for the help. But you can't seem to understand what I want.

Yes, this will work. Thanks a lot for the response.