TMS320F28379D: Using High-resolution period control to generate a 6.78MHz clock

Hi Zhu,

For specific HRPWM frequency information, please refer to the device datasheet sections 6.11.2.2 ePWM Electrical Data and Timing and 6.11.4 High-Resolution Pulse Width Modulator (HRPWM):

You PWM frequency is dependent on several parameters such as your clock frequency (EPWMCLK), clock dividers, count mode (up/down/up-down), period value (TBPRD), etc. The duty cycle is dependent on what event(s) you use to signal your PWM frequency to go high/low (such as CMPA/CMPB/CTR=/CTR=PRD etc.).

Here are some helpful resources for EPWM usage with calculation examples you can use in determining your PWM configuration for this such as:

1.  EPWM developer's guide, which walks through a very clear and simple setting up of the EPWM using all of the various submodules. It shows how you can easily configure this using the sysconfig GUI, but also does show the driverlib code as well. 
2. Another resource is the EPWM video series. You can watch through all of them (they are pretty short videos) or also skip to the submodules you are having trouble with.

For HRPWM, there are some example HRPWM calculations in the device TRM as well, such as 15.14.1.5.2 Scaling Considerations. 

Best regards,

Allison