PPK2 with Python API causes error (PPK2 blinking red)

[rene-xyz]

Hi everyone!

Setup:

Currently, I am using the nRF52840 DK board to evaluate neural network models directly on the nRF microcontroller. To measure the power consumption when running a model, I use the PPK2. Since I want to optimize my models, I evaluate them all in runs of several hours. To fully automate this, I use the PPK2 Python API (multiprocessing version, i.e. PPK_MP class) within a newly started subprocess to measure the power for a model when I start inference on the nRF52840 from another process. I am using the PPK2 Python API as described in the documentation.

Problem:

The previously described procedure works fine for several hours. At some point (I could not reproduce it on purpose) the PPK2 starts blinking red rapidly and does not work at all. My question now is if anyone has experienced similar behavior or even has a solution so that this will no longer happen.

Please let me know if you need more information. Thank you already for your help!

Best, René

[Jørgen Holmefjord]

Hi,

Do you only see this issue when using the IRNAS PPK_MP class API? As this API is not developed by Nordic, you might need to check with the developers if they have seen this issue.

How frequently/rapidly does the red blinking occur? Do you need to reset the PPK to get it back to normal operating mode, or is it sufficient to stop/restart the script? It could sound like two instances are racing for access to the serial instance, as it will reboot at disconnect. Do you have any information about what the script is doing when the issue occurs?

Best regards,
Jørgen