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

[Learner]

Hi Hakon,

Thank you for your reply where you answered my 4 questions.

I think I can see clearer what is going on between app and network cores in the die temperature example.

Håkon Alseth said:

Once the above configuration is enabled, then it should print the temperature w/o attaching the RTT session.

Håkon Alseth said:

CONFIG_BOARD_ENABLE_CPUNET=y

If I understand you right, once I add the above config line in the app_core prj.conf then the network core will boot up automatically (well in fact the app core will boot it up I guess). So, the reason I was not seeing temperature values until J-Link RTT viewer connected is because the network core did not boot up and needed an external entity to kick start it.

Kind regards

Mohamed

[Håkon Alseth]

Hi Mohamed,

 

Learner said:

If I understand you right, once I add the above config line in the app_core prj.conf then the network core will boot up automatically (well in fact the app core will boot it up I guess). So, the reason I was not seeing temperature values until J-Link RTT viewer connected is because the network core did not boot up and needed an external entity to kick start it.

That is correct. SEGGER has scripts that automatically boots up the network core for you when you start a RTT session.

 

Kind regards,

Håkon 

[Muhammed]

2678.Desktop.rar

[Muhammed]

I did what you said, why can't I see the exit?

[Håkon Alseth]

You are posting in a very old thread. Please create a new one with your questions.

 

Kind regards,

Håkon