NFC problem on nRF52840 when using mesh DFU bootloader.

RE: NFC problem on nRF52840 when using mesh DFU bootloader.

Simonr — Wed, 11 Nov 2020 13:37:47 GMT

Hi Tony

Edvin is currently on leave, and I have been tasked to look after this case while he's away. I'm sorry about the late reply, but we just now got to his backlog.

Please note that if you're using SDK v17.0.0 it is strongly recommended to switch to SD v17.0.2, as this is a bug fix release replacing v17.0.0.

Regarding Edvin's questions in his last reply, when running the NFC with the default bootloader, are you able to use a logic analyzer or similar to see if there is any "action" at all on the NFC pins (P0.09 and P0.10)? While debugging, are you able to see any differences in the nfc_init() function at all between using the default bootloader and the one excluding the init_clock() function?

Best regards,

Simon

RE: NFC problem on nRF52840 when using mesh DFU bootloader.

TonyAkiki — Fri, 06 Nov 2020 07:46:22 GMT

Here is my different versions I use:

nrf mesh sdk v4.2.0
nrf sdk v.17.0.0
softdevice s140_nrf52_7.0.1_softdevice
mesh_bootloader_gccarmemb_nrf52840_xxAA

When using NFC library with a mesh application and default mesh bootloader everything seems to work fine ...main is reached nfc init function is reached without problem , no crashes no errors BUT I cant scan the NFC tag with my phone ... nothing is detected!

RE: NFC problem on nRF52840 when using mesh DFU bootloader.

Edvin — Thu, 05 Nov 2020 12:48:25 GMT

It may be that the NFC is checking whether the clock is running, and requesting the clock only if it is not.

What SDK version and mesh SDK version are you using?

I have not been able to replicate this, but I have not imported the NFC libraries to a mesh example. I tried to add the same init_clock function to the beginning of the record_text nfc example from SDK17. I did not find any issues there. What does it behave like? Does the app crash when you don't comment out the init_clock function in the bootloader? What does the application behave like? Is the main() function reached? Is the nfc init function reached? Does it return any errors?

If you are content with the workaround to comment out the init_clock() function from the bootloader, that is perfectly fine. No need to reply. If you want to try to find the reason, we can continue to dig a bit for the reason for this issue. If so, do you have a mesh example that replicates this issue when you program the default bootloader?

BR,

Edvin

RE: NFC problem on nRF52840 when using mesh DFU bootloader.

TonyAkiki — Thu, 05 Nov 2020 12:15:35 GMT

Yes the bootloader still working!
It feels actually strange that initiating the clock in the bootloader affects the NFC.

RE: NFC problem on nRF52840 when using mesh DFU bootloader.

Edvin — Thu, 05 Nov 2020 08:36:29 GMT

The softdevice will start the clocks, yes.

What I find strange is that if the bootloader starts the clock, the NFC doesn't work. However, as long as you start the clock from your application (which the softdevice does), it shouldn't matter that you comment it out in the bootloader.

Perhaps it is one of the init functions in the NFC libraries that doesn't like that the clocks are running from the start.

Your bootloader still works, right? After you comment out the clock init function?

BR,

Edvin

RE: NFC problem on nRF52840 when using mesh DFU bootloader.

TonyAkiki — Wed, 04 Nov 2020 14:34:27 GMT

Hello Edvin,

As i mentioned before, I had no issues when running just the application and softdevice without the bootloader,

Commenting out the clock_init() in the mesh bootloader seems to fix the NFC issue. It does not either seems that the application run into issues. And above all the NFC works again! I guess the softedvice configure and start the clock but not sure about it!

RE: NFC problem on nRF52840 when using mesh DFU bootloader.

Edvin — Wed, 04 Nov 2020 14:06:55 GMT

Hello,

As you said in your private ticket, the clock is started in the bootloader, and it works if you comment out this in the bootloader. In that case, I would recommend that you make sure it is running from the application.

Did you try to debug the application before modifying the bootloader? Does the application run into any issues? Is the error handler picking up something, or is the application running as before?

Best regards,

Edvin