Unable to change WDT reload value in FreeRTOS example.

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Tue, 05 Dec 2023 13:04:52 GMT

Yes.

Thanks

RE: Unable to change WDT reload value in FreeRTOS example.

Susheel Nuguru — Tue, 05 Dec 2023 12:51:24 GMT

That makes sense Vishnu. Thanks for updating this thread with the full info. Can we now close this thread?

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Tue, 05 Dec 2023 11:33:16 GMT

Figured out this. There is a GPIO interrupt which is actually waking the system up in second case(sending a command) and is initialized a little late in code. That's the reason it was not working in first case. .

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Tue, 05 Dec 2023 07:17:48 GMT

It is going to system off mode but the sd_nvic_systemreset is not restarting the application. This is working if I send a command. I tried to do immediately after BLE initialisation.

RE: Unable to change WDT reload value in FreeRTOS example.

Susheel Nuguru — Mon, 04 Dec 2023 11:56:21 GMT

It should make the chip go to systemoff at any stage. Not sure why it is working only when you send a command.

How early are you calling system off in the application? Are you doing this after you setup the wakeup source and make sure that the wakeup source is not active?

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Fri, 01 Dec 2023 07:39:18 GMT

Ok. But any idea why it is not resetting to the application and going to system off mode if I do in the beginning of code and working if I send a command to do systemoff.

RE: Unable to change WDT reload value in FreeRTOS example.

Susheel Nuguru — Fri, 01 Dec 2023 06:36:29 GMT

[quote user="viznu3391"]So the problem is WDT is not getting disabled with sd_nvic_systemreset. That is why I tried with sd_power_system_off and then reset. This time it was able to change the preload value. Only a WDT reset or a POR can only disable the WDT and thereby reconfigure the WDT, if my understanding and experimentation is correct.[/quote]

Your observation and understanding is correct. If you can look into the POWER-Reset-Retained Registers section. You can see in the table that for Soft-Reset (nvic_systemReset) the watchdog is not reset and will retain its registers and hence its old configuration. And you can also see that with System OFF mode reset, the WDT registers are reset. So it is best to use systemoff if you want to automate this.

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Thu, 30 Nov 2023 16:54:40 GMT

Yes correct. We added WDT as a fail safe mechanism to restart the system if there is no BLE events for 24 hours. Later we tried to reduce the preload value to 2 hours and tried OTA and realised WDT is not resetting system after 2 hours, but only after 24 hours. Then started digging.

So the problem is WDT is not getting disabled with sd_nvic_systemreset. That is why I tried with sd_power_system_off and then reset. This time it was able to change the preload value. Only a WDT reset or a POR can only disable the WDT and thereby reconfigure the WDT, if my understanding and experimentation is correct.

Even we didn't like the workaround as we don't know what other things can break because of this. Can you try it on your side and check if it is working without this workaround.

RE: Unable to change WDT reload value in FreeRTOS example.

Susheel Nuguru — Thu, 30 Nov 2023 13:59:00 GMT

Hmm, let me see if I understand this correctly.

You have an advertising issue which was the main reason to look into reset. And you looked in WDT as a workaround to reset the chip for that. And you see issues with the WDT with time and then you are using soft reset as a workaround to the issue to the WDT.

I do not understand why your WDT issue is not working correctly. You need to debug that first by disabling everything else apart from the WDT feature. I have not seen WDT not functioning this way before.

[quote user="viznu3391"]But for some reason this is not resetting the system. But if I explicitly do sd_power_system_off and sd_nvic_SystemReset by sending a command it is working as expeced. [/quote]

This is again workaround to a workaround and I do not know the context in which you are calling this. Why would you do system_off and system_reset at the same time? These two are different things. If you just want a reset, you should just call a sd_nvic_systemreset. And that should work.

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Thu, 30 Nov 2023 12:43:02 GMT

I tried the following flow. Basically after wdt enable. just read the reload value using nrf_wdt_reload_value_get and then compare with WDT_CONFIG_RELOAD_VALUE. If not matching then restart the system using sd_power_system_off(); & sd_nvic_SystemReset(); . But for some reason this is not resetting the system. But if I explicitly do sd_power_system_off and sd_nvic_SystemReset by sending a command it is working as expeced. Any idea why the first method is not working?

Or can you give a better solution.?

Thanks,

Vishnu

RE: Unable to change WDT reload value in FreeRTOS example.

Susheel Nuguru — Thu, 30 Nov 2023 12:36:28 GMT

thanks for letting us know the fix Vishnu. Maybe we can close this thread now?

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Wed, 29 Nov 2023 11:52:23 GMT

Got the issue. Only a sd_power_system_off or WDT reset can be able to change the settings again. Added sd_power_system_off and system reset in application flow to achieve this.

Thanks

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Wed, 29 Nov 2023 09:36:58 GMT

Tried in debugging and changed the reload value from 24 hours to 2 seconds also. Played with different values. But the value comes out to be 0x0e100000 everytime.

RE: Unable to change WDT reload value in FreeRTOS example.

Susheel Nuguru — Wed, 29 Nov 2023 08:57:52 GMT

Hi Vishnu,

I have not seen any issue with the WDT code in yours but just to be sure, can you start your application in debugger mode and after you set the WDT reload value, can you try to read those registers in the NRF_WDT and see if the set value is changed from 24 hour to 2 hour ticks?

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Wed, 29 Nov 2023 05:49:43 GMT

HI Susheel Nuguru ,

We've set initially enabled the WDT to 24 hours and then tried to change to 2 hours. Now we see that device is not resetting after 2 hours of inactivity. It still takes 24 hours. We want to reduce the WDT to 15 minutes or less. But unable to set the reload value as in startup it shows wdt is running with nrf_wdt_started() call. What is the way to reset and change the reload value? Tried with wdt example and behavior is same.

Thanks,

Vishnu

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Tue, 28 Nov 2023 05:09:58 GMT

Sorry. That is being discussed in a private thread. here

Can you check the SDK config and watchdog_enable and wdt_feed functions in main.c

RE: Unable to change WDT reload value in FreeRTOS example.

Susheel Nuguru — Mon, 27 Nov 2023 18:45:34 GMT

Hi Vishnu,

I am sorry but I cannot find the project that you shared with me. Can you please share the project or the link again? WDT is very mature solution on nRF52840 and has been tested with many FreeRTOS projects. So it has to be some configuration issue.

RE: Unable to change WDT reload value in FreeRTOS example.

Vishnu Pradeep — Mon, 27 Nov 2023 11:26:15 GMT

Susheel Nuguru Can you go through the WDT settings in the project we've shared earlier?