• State TI Thinks Resolved
  • Locked Locked
  • Replies 4 replies
  • Answers 2 answers
  • Subscribers 83 subscribers
  • Views 479 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS320F28032: EPWM2 abnormal at startup

Jeff Chen71
Expert 1345 points

Part Number: TMS320F28032

Hi,

        My custromer config EPWM1 and EPWM2  for LLC. If they use jtag to download the firmware it is good. But if using cutomer bootloader to download then it has posibilitypwm2 hold high level for serveral ms at EPWM1/2 startup. After serveral ms or power cycle then the EPWM2 resume normal. Attached abnormal waveform and code of EPWM initial.

waveform and code.docx

  • 0
    TI__Mastermind 42195 points

    Jeff,

    If this problem only occurs when using the custom bootloader, I expect the problem is in the bootloader.

    1. Is the bootloader in the begining of your code, or does the PWM initialization code run first?
    2. Do you have any pull-up resistors that could be causing this?
    3. What is the configuration of the GPIO mux when the bootloader is running?

    Before running the bootloader try configuring the PWMs as inputs or if you need a driving source configure them as an output and set the GPIO Data register to 0.

    Regards,
    Cody 

  • 0 in reply to Cody Watkins
    Prodigy 30 points

    Hi Cody ,

    Thank you for your reply! But there are still some puzzled.

    1.It ocurrs after main code re-start. the pwm signal given in ISR. At the begining of start-up, it is ok for PWM1A and PWM2A, low level.

    2. We expect the out of PWM1A and PWM2A is synchronization, but there are phase shift.  Or PWM1A is normal, PWM2A is constant high level. The configuring of PWM affects the result, but we didnot know why it was, and how to slove it.

    3.The ISR code is assembler language, the result is different when the location of some statement is different.

     Look forward to your reply ! Thank you !

    Best regards

    Ye

  • 0 in reply to ye hu
    TI__Mastermind 42195 points

    Ye,

     can you stop the program before or after the boot loader? Please check the configuration of GPIOs and PWMs before and after the custom bootloader. This should help us understand what is going on.

    Are you using pull-up resistors on your PWM outputs?

    Regards,
    Cody 

  • 0 in reply to Cody Watkins
    TI__Mastermind 42195 points
    Ye,
    Are you still working on this issue?

    Regards,
    Cody