How to reset main embedded application within nRF52810 without resetting flash or powering off the MCU?

RE: How to reset main embedded application within nRF52810 without resetting flash or powering off the MCU?

Susheel Nuguru — Thu, 08 Jul 2021 06:13:28 GMT

If you look at this table which explains peripherals behavior at different reset, you can notice that a soft-reset (NVIC_Reset) will reset the GPIO peripheral resettings its configuration and states. The table also shows that during deep sleep and wake up from deep sleep, the GPIO module is not reset as you noticed

RE: How to reset main embedded application within nRF52810 without resetting flash or powering off the MCU?

Noah — Wed, 07 Jul 2021 20:31:41 GMT

Okay great, thank you.

What is the behavior for GPIO? I control various digital logic blocks with GPIO outputs (HIGH or LOW). Even if sd_nvic_systemreset() is called, I need to ensure that the GPIO levels (for configured pins) do not change even briefly during the reset. I know that if I go to deep sleep and am holding a GPIO at LOW output, it will remain this way in and out of whatever sleep I want to do (besides full shut down of course). Is this the same for nvic_systemreset?

I set the pin logic right at the beginning of my main application, so restarting the main application code would not change the pin logic output levels (as they'd just get set to what they were set to already). however, if the GPIO outputs change or become undefined temporarily during the sd_nvic_systemreset, this is bad for my application.

Can you please share some documentation on to what sd_nvic_systemreset does? What does it mean to "reset" in this fashion, what things are reset and what kind of things happen before the application is restarted?

RE: How to reset main embedded application within nRF52810 without resetting flash or powering off the MCU?

Susheel Nuguru — Wed, 07 Jul 2021 06:34:44 GMT

Hi Noah,

I do not think that using NVIC_SystemReset() API will cause any flash corrupted for an already written data. However it is good practice to always use SD provided API for restricted peripheral access

RE: How to reset main embedded application within nRF52810 without resetting flash or powering off the MCU?

Noah — Tue, 06 Jul 2021 23:48:33 GMT

I believe I need to use sd_nvic_systemreset() instead, which I am now trying. I use the soft device s112, my application is constructed on top of the uart example.