How to implement issue [20] from the errata: "RTC: Register values are invalid"

[SeanK]

Errata for nRF52832 Rev 2 version 1.2, errata item 20, RTC: Register values are invalid, has a recommended workaround that i'd like to ensure i've implemented correctly - "Execute the below code before you use RTC:".

"...before you use RTC" seems broad to me, and i'd like clarification please. Do I issue this code before any calls to nrf_drv_rtc_counter_get(), or do i need to do it before nrf_drv_rtc_enable(&rtc)?

Do i need to think about app_timer.c, and how it uses the RTC? What about the softdevice?

Do you have any examples of how you've implemented this workaround?

Thank you very much!

[ovrebekk]

Hi 

You only have to run the workaround at the start of the program, before you configure the RTC. Not every time you need to access it. 

Starting the LF clock is always necessary if you want to use the RTC, and as long as you trigger the STOP task after the LF clock is started, before you configure and use the RTC, then you shouldn't have any problems. 

You won't have to worry about this workaround when using the app_timer module or the SoftDevice, as they have been designed with this issue in mind. 

Best regards
Torbjørn