• State Verified Answer
  • Replies 19 replies
  • Subscribers 69 subscribers
  • Views 15890 views
  • Users 0 members are here
Attachments (0)
Nordic Case Info
  • Case ID: 109035
Options
This post is older than 2 years and might not be relevant anymore
More Info: Consider searching for newer posts

measuring input GPIO pin frequency with soft device running

adriand

Hello,

is it possible to measure frequency from 1Hz up to 400kHz (50% duty cycle) on gpio pin having soft device enabled with Peripheral functionality? The measurement will be invoked on demand by the connected central device. I will use nRF51822, rev. 3, S110 or S130, SDK 8 or 9.

If this is not possible, please tell me if following scenario would be ok:

  • invoke measurement
  • disable soft device (disconnection from central)
  • manage measurement (what's the best way: which timer?, PPI? GPIOTE?)
  • enable soft device

Thank you!

btw, what is the maximum frequency that can be measure on gpio pin?

Parents
  • 0

     

    Followed same stratergy , same code for a similar requriment if frequency measurement. Able to get frequency count in gpio. But when we left it for a long run of 48 hours, we observed a one side always decreasing frequency. Screenshot of counter shared. We know both external source frequency and hfclk will have some temperature component. But instead of periodic ups and down it just kept on decreasing one way. We are yet to found a reasonable explanation fir this. External frequency is tested with with another probe and result in a fix frequency slightly going up and down with ambient temperature in a day cycle. Any pointer regarding this is highly appreciated. 

    48hour frequency reading

    drive.google.com/.../view

Reply
  • 0

     

    Followed same stratergy , same code for a similar requriment if frequency measurement. Able to get frequency count in gpio. But when we left it for a long run of 48 hours, we observed a one side always decreasing frequency. Screenshot of counter shared. We know both external source frequency and hfclk will have some temperature component. But instead of periodic ups and down it just kept on decreasing one way. We are yet to found a reasonable explanation fir this. External frequency is tested with with another probe and result in a fix frequency slightly going up and down with ambient temperature in a day cycle. Any pointer regarding this is highly appreciated. 

    48hour frequency reading

    drive.google.com/.../view

Children
No Data
Related