• State
  • Locked Locked
  • Replies 6 replies
  • Subscribers 82 subscribers
  • Views 519 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.

generating pulses in 28069

Rakshita Dhar
Prodigy 120 points

Other Parts Discussed in Thread: CONTROLSUITE, TMS320F28069

Hello,

I need to generate pulses from 28069 piccolo stick. I require 37 kHz frequency pulses with 18% duty cycle.

And also 37 kHz, 18% duty cycle pulses which are phase shifted by 50% from the pulses mentioned in the above sentence.

Even if  i am changing TBPRD, frequency of pulses does not change. It remains 20 kHz only. How do i change it to 37 kHz ? 

  • 0
    Guru 192875 points

    Hi Rakshita,

    Even if  i am changing TBPRD, frequency of pulses does not change. It remains 20 kHz only. How do i change it to 37 kHz ?


    Did you try with this example: C:\ti\controlSUITE\device_support\f2806x\v136\F2806x_examples_ccsv5\epwm_up_aq

    Try changing the TBPRD value here and let us know what you observe.

    Regards,

    Gautam

     

  • 0 in reply to Gautam Iyer
    Prodigy 120 points

    Hello,

    The problems which i stated are clarified now. I got the required pulses. But now a new problem is there. There are six output - 1A, 1B,2A,2B,3A,3B.

    A and B are complimentary to each other. And between 1 , 2 and 3 we can provide phase shift.

    But i do not need A and B to be complimentary. How can i do this ? I need A and B to be independent of each other.

    Also i wanted to ask whether from one pin of DSP we can take out two wires. Eg : pin 13 is 1A. So can i take two wires from there so that i get same kind of  pulses twice ?

    Thanks

  • 0 in reply to Rakshita Dhar
    Guru 192875 points

    But i do not need A and B to be complimentary. How can i do this ? I need A and B to be independent of each other.

    I hope you're reading the SPRUH18D - Technical Reference Manual for TMS320F28069. All the configurations with codes are clearly mentioned! Pg. 273 onwards.

    Also i wanted to ask whether from one pin of DSP we can take out two wires. Eg : pin 13 is 1A. So can i take two wires from there so that i get same kind of  pulses twice ?

    This is not recommended; this might damage the ePWM peripheral.

    Regards,

    Gautam

  • 0 in reply to Gautam Iyer
    TI__Guru 57255 points


    Also i wanted to ask whether from one pin of DSP we can take out two wires. Eg : pin 13 is 1A. So can i take two wires from there so that i get same kind of  pulses twice ?


    You could.  You will just need to make sure that the PWM provides enough drive strength to drive what you need.  The device's datasheet will provide the drive strength specification for your particular device.


    Thank you,
    Brett

  • 0 in reply to Gautam Iyer
    Prodigy 120 points

    I got the required pulses. I read the manual . thanks.

  • 0 in reply to Brett Larimore
    Prodigy 120 points

    I checked in datasheet. Thanks.