NRF52 softdevice changing application timing

RE: NRF52 softdevice changing application timing

Susheel Nuguru — Thu, 03 Nov 2016 11:19:07 GMT

ok, hopefully you will see better timing.

RE: NRF52 softdevice changing application timing

yaron — Thu, 03 Nov 2016 10:38:14 GMT

Hi Aryan. I am sorry, my function was not running inside the callback. I will try again and update you.

RE: NRF52 softdevice changing application timing

yaron — Thu, 03 Nov 2016 09:58:11 GMT

I'm sorry, but I can't post the code. Basically what I do is measure ADC values and change some periperals configuration usign SPI. I am not calling any sd_xxx functions.

RE: NRF52 softdevice changing application timing

Susheel Nuguru — Thu, 03 Nov 2016 09:42:34 GMT

It is difficult to answer this without seeing your loop code and where it is called. Can you please post the loop code if possible or explain in detail of what it does. Does it call any sd_xxx calls+

RE: NRF52 softdevice changing application timing

yaron — Thu, 03 Nov 2016 09:01:05 GMT

Aryan, Let me explain what I see. I am measuring my loop length (in us). when softdevice is disabled, I get the same resualt (1022) for all function calls. when softdevice is enabled (and device is paired), I get results between 1053 - 1090. Can you explain this behaviour?

RE: NRF52 softdevice changing application timing

Susheel Nuguru — Thu, 03 Nov 2016 08:51:33 GMT

During the timeslot, there must be no other softdevice activity at all. All softdevice reserved peripherals become available to the application during that timeslot. So when application uses that slot then softdevice have to re-initialize those peripherals. Also the timeslot callbacks are called with highest possible priority (priority 0) , so the application running inside the callback cannot be anyways interrupted according to ARM NVIC interrupt priority rules.

RE: NRF52 softdevice changing application timing

yaron — Thu, 03 Nov 2016 06:26:33 GMT

Hi Aryan. I am using the Timeslot API. Is there supposed to be no softdevice activity at all during my timeslot, or is it just uninterrupted by radio activity?

RE: NRF52 softdevice changing application timing

Susheel Nuguru — Wed, 02 Nov 2016 19:54:20 GMT

Hi, best is to use Timeslot API where the softdevice will give you a request timeslot where your application is promised not to be interrupted by softdevice during that slot. I see this API will be best fit (or probably only fit) for your usecase.