TMS320F280025C: Adjust PWM frequency and phase

I'll check in to this and see what I can find.  However, due to local holidays, it will be a week or so before I can get back to you.

--Paul 

Looking forward to your answer

Can you confirm the part number of the device you are asking for.  This 37+ year old DSP (not a C2000 device) does have a timer, but does not appear to have a PWM capability. 

--Paul 

Sorry, I made a mistake in the chip model; The correct model is TMS280025C；Now I understand the problem, which is that when I shifted the phase, I crossed the CMP value, causing the waveform to not flip. However, my requirement is that the phase change from small to large must exceed the CMP value, so is there any way to solve it? We look forward to your reply.

No problem. I'll move the thread to the correct team and they should pick it up from there.

--Paul 

ok，thanks for your help.

Hi ?? ?,

?? ? said:

How to freely adjust the frequency and phase of PWM? Now I have found that when the frequency of PWM changes, if the phase does not change correspondingly, it will cause waveform interruption and output, and it is also related to waveform synchronization. I want to know how to operate it to achieve frequency and term shifting as desired

Have you been able to look at our synchronization examples found within our C2000WARE SDK? 

To change the phase you will need to enable phase shift loading for the slave EPWMs and configure the sync input for the slaves.

Best,

Ryan Ma

Now I understand the problem, which is that when I shifted the phase, I crossed the CMP value, causing the waveform to not flip. However, my requirement is that the phase change from small to large must exceed the CMP value, so is there any way to solve it? We look forward to your reply.

the issue is same as the  below website

TMS320F280049: Synchronization causes PWM losing issue - C2000 microcontrollers forum - C2000︎ microcontrollers - TI E2E support forums

When changing phase from small to large, it is important to know the timing of when sync occurs. 

You could use T1/T2 events based on a sync event to toggle our PWMs low/high for example.

You could also use global load if needed to load shadow to active based on a sync event to update the CMP values.

Best,

Ryan Ma

Thank you for your reply. I will try your method