RTC1 not reset after DFU

[Ian]

I'm using an app timer to blink an LED while in the bootloader.

Initially I was configuring an app timer when the bootloader started up and never stopped it, assuming the reset would clear any RTC1 settings. I noticed that following a DFU, anything utilizing RTC1 was then ticking at a much higher rate. In the app, RTC1 is normally configured to 1kHz. Disabling the app timer prior to booting the app seemed fix the issue.

My question is, are the RTC1 settings not able to be changed unless the timer is stopped, even following a reset? Also, is there a way to uninit RTC1 from the app without needing the timer instance from the bootloader?

Regards, Ian

[Hung Bui]

Hi Ian,

After DFU the bootloader won't reset. It branch directly to the application. So if you don't stop the RTC it will keep running when you switch to application with all the settings. You should stop the RTC/apptimer prior to jump to application. And in your application, you should make sure all the registers are re-configured. Should not expect all the registers are at the reset state when you start your application.

[Ian]

Hi Hung, I'm using freeRTOS which configures the RTC1 registers, but I assume since the timer wasn't being stopped that it wasn't able to be reconfigured. I reset the timer on application start as per your suggestion. Thanks for the help.