CTU reloading to be slower than PWM reload

[xaing_wang]

Hi everyone,  think you for your help! 

    I want that the PWM reload cycle is 50us, and the CTU reload cycle is 100us. Due to the CTU MRS(Master Reload Signal) selected PWM_REL，so it is must reduce once the MRS in CTU. Another way is setting  to turned for the PWM_REL.

   Who can help me? It lock as if difficulty on MPC5744.

[petervlna]

Hello,

Could you please explain what you are trying to achieve in detail.

It is not clear from your description.

CTU follows it input triggers (PWM or any other source). CTU then starts conter and once it reach first trigger point CTU will generate request to CTU SU (scheduler subunit) to generate ADC conversion or other actions.

I have released AN dealing with the PWM CTU aligment in details.

Please have a look on it:

https://community.nxp.com/docs/DOC-102559 

Example MPC5744P FlexPWM CTU ADC synchronization GHS614 

The PWM CTU modules are same for MPC5643L and MPC5744P.

regards,

Peter

[xaing_wang]

Hello Peter，Think you for your response!

   Now, I try to disable "Input 0 Rising Edge Enable" bit in CTU_TGSISR register when the first PWM cycle will over。I think it filters the first MRS，and Iwill enable this singnal before second PWM end time。

[petervlna]

Hi,

You have to first configure CTU and last thing you will do is to start PWM.

If you do it vice versa you will surely miss frst MSR.

regards,

Peter