C2000 LaunchPad PWM

Have you downloaded controlSUITE and looked at any of the ePWM examples?  

A good one to start with might be \controlSUITE\device_support\f2802x\vXXX\f2802x_examples\epwm_updown_aq

Thank you for your responding.

I looked that example but how can I change the duty cycle in this example?

Thanks again.

Regards.

Metin.

Hi Devin.

Actually I have following code and I have just generate PWM but my new problem is changing the duty cycle of PWM.

I want to change the duty cycle.

Could you help me about this? 

Thank you so much.

Regards. 

Metin.

Hi Trey,

I have tried it many times but it does not affect anything.

Duty ratio does not change with this method.

Trey,

I have just modified my code and it work such as you said. I mean, CMPA value changes the duty ratio.

Thank you so much. But as a last question, I use equations for output PWM signal frequency and the duty ratio. These are:

Output PWM frequency = f(cpu)/[T(timer)*ClkDiv*HspClcDiv]

Duty ratio(%) = (CMPA*100)/(T(timer)+1)

T(timer) is also called TMPRD.

With these equation, I obtain frequency and duty ratio what I want to get. I tried it many times and these equations are working correctly.

What do you think about these equations?

Are they correct?

Thank you.

Metin

These equations seems correct.  Are they not yielding the correct values?  If not, by what factor are they off?  Is the duty cycle correct, but the frequency is off?  Please give more information.

Trey

Trey,

They are yielding correct values. I have no problem with the results of these equations but I just wonder is there any problem with them.

Actually, there was a frequency equation in TIs controlstick labs pdf. but it did not work in my code and I modified it as I said before. And now I have a doubt about their reliability although I get true results. 

I want to colsult with you about their reliability.

Thank you so much.

Metin

Hi Trey,

I want to ask a question to you.

I want to obtain complemantary PWMs on PWM1A and PWM1B with deadband.

If I use deadband codes, PWM1A and PWM1B are not working as a complemantary but deadband works.

I want bot complementary operation and deadband.

How can I do?

Edit: Trey I have just done it.

Thank you.

Metin Ozturk

I want to know the generation of Pwm. step by step procedure. Is there any documents regarding how to generate please send. I want to know each and every step what is going on..... I have to modify on presently working project which is Solar micro Inverter. So Please send



ThankYou & Regards
Mahesh