• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 82 subscribers
  • Views 172 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.

TMS320F28069: kick-start ADC

Hisui Yan
Prodigy 180 points
Part Number: TMS320F28069


I found that in many example programs, the SOCx flag are forced to be 1 (by setting ADCSOCFRC1) after the ADC was configured (like assigning triggers to the SOC, and assigning SOC to ADC pins). So could anyone tell me why we need the "kick-start ADC"?

  • 0
    Guru 14640 points
    As I understand it, it is a "software trigger." Many ADCs can be tied to events like PWM or counters, but if you have an independent event (one that is not tied to the existing event matrix), it is useful to have a "software trigger" mechanism.

    Hopefully, that helps.
  • 0 in reply to Todd Anderson78572
    TI__Guru 62975 points
    As Todd mentioned, the ADCs only perform conversions when triggered. There are multiple trigger sources for starting ADC conversions including software (from CPU), self (from ADCINT), and system (from peripherals like ePWM, Timer, GPIO, etc). The examples tend to use the most convenient trigger source depending on the desired task.

    For example, when sampling for offset calibration, the example uses self-triggering to capture a continuous stream of conversions. This is more convenient and quicker to execute than triggering from another peripheral. However, the self-triggering scheme relies on the ADCINT signal, which is only generated at the completion of a specific SOC. The CPU software trigger is used to kick-start the scheme so that the first ADCINT signal can be generated.