Zephyr API to read the nRF5340 die temperature

[Learner]

Hello,

I am looking for some some nRF5340 example code that reads the nRF5340 die temperature using zephyr APIs.

I've looked at previous posts but I could only find this one https://devzone.nordicsemi.com/f/nordic-q-a/56171/how-to-get-die-temperature-on-nrf52832-using-zephyr from 10 months ago that stated none existed. I am hoping someone, somewhere musty have done something similar.

Thank you.

Kind regards

[Håkon Alseth]

Hi,

 

The temp peripheral is only accessible on the network core:

https://infocenter.nordicsemi.com/topic/ps_nrf5340/temp.html?cp=3_0_0_6_33

So we need to configure the board nrf5340pdk_nrf5340_cpunet, but since the network core is started from the app cpu, you first need to have something on the app core running with this config set:

CONFIG_BOARD_ENABLE_CPUNET=y

 

I used sample/nrf5340/empty_app_core.

 

For uart output from the network core, connect P0.25 to P0.20.

If you also need UART RXD, connect P0.26 to P0.22.

 

Here's an example that shows how to use the NRF_TEMP peripheral: 

0677.nrf_temp_sample.zip

 

Kind regards,

Håkon

[Learner]

Hi Hakon,

I have built and run the project that reads the die temperature. I can see the see the temperature values going up and down as I heat and cool the device. However, I am still not clear how to read these values from the network core into my application. 

Please advise.

Kind regards

Mohamed

[Håkon Alseth]

Hi,

 

Here's a small example on how to share data between the two cores.

Note that I setup the network core to use RTT for printing, and the app core uses uart.

share_temp_data_nrf5340.zip

 

The above example uses linker sections to share the RAM mapped shared address space, and it is provided as-is.

You can have a look at these samples, if you need to share data between the cores as a part of a larger scheme:

https://github.com/nrfconnect/sdk-nrf/tree/master/samples/nrf_rpc/entropy_nrf53

https://github.com/nrfconnect/sdk-zephyr/tree/master/samples/bluetooth/hci_rpmsg

 

Kind regards,

Håkon

[Learner]

Thank you Hakon.

I have just seen your reply. I have been checking my inbox for a notification email from DevZone informing me you've updated my ticket. However, for some reason I did not get a notification despite the fact Notifications are enabled.

Anyway, I will have a look at your example and let you know how I got on.

Kind regards

Mohamed

[Håkon Alseth]

Hi Mohamed,

 

Learner said:

I have just seen your reply. I have been checking my inbox for a notification email from DevZone informing me you've updated my ticket. However, for some reason I did not get a notification despite the fact Notifications are enabled.

Could you check if the notification is ticked under "settings -> notifications"? Specifically this one?

 

Learner said:

Anyway, I will have a look at your example and let you know how I got on.

as mentioned, it is a very simplistic example, which statically declares a region of RAM, and the network core essentially writes into this RAM address based on when the IPC event occurs. It does not have much error handling wrt. synchronizing.

 

Kind regards

Håkon

[Learner]

Hi Hakon,

Yes, every item is ticked. I did receive notifications in the past, the last one back in January 19 2021. I also received two more on Feb 16 2021 after a password reset request.

Kind regards

Mohamed

[Håkon Alseth]

Hi Mohamed,

 

My apologies for this. Im currently checking with the site administrators to see if we can figure this out.

 

Kind regards,

Håkon

[Learner]

Hi Hakon,

I have received a notification about your previous reply. Have you made any changes on your side? Anyway, Notifications are working now.

I still have not had a chance to try your proposed die temperature solution. While waiting for your response I started another task and I need to complete it before I can go back to the die temperature. I will probably look at it sometimes tomorrow.

Kind regards

Mohamed

[Håkon Alseth]

Hi Mohamed,

 

Learner said:

I have received a notification about your previous reply. Have you made any changes on your side? Anyway, Notifications are working now.

I am glad to hear that the notifications are now working!

 

Learner said:

I still have not had a chance to try your proposed die temperature solution. While waiting for your response I started another task and I need to complete it before I can go back to the die temperature. I will probably look at it sometimes tomorrow.

No worries. If you run into any issues, please let us know.

 

Cheers,

Håkon