Hello,
Thank you for your inquiry.
It seems that IAR tries to configure tracing automatically each time a J-Trace debug probe is used...
This is of course in cases like yours unwanted behaviour. Usually we suggest our IDE partners to implement the trace functionality as a opt-in function to avoid this problems.
Unfortunately there seems to be no opt-out in this case as well.
The closest thing i could find was the setting J-Link/J-Trace-> Setup -> ETM/ETB -> check "Prefer ETB"
This should disable automatic ETM setup and it will try ETB setup instead. The Nordic chip does not have ETB avaialble, but the error message for a failed ETB setup should be less intrusive.
Does that work as a workaround for you?
Second question: we probably need to redesign the target hardware. Will tracing work if I just add TRACEDATA[0..3] and TRACECLK pins or do I need more?
That is all you need for optimal ETM tracing.
SWO is a different kind of tracing and is not to be paired with ETM pin trace.
Should you be looking into tracing we offer example projects for many different MCUs. We also have one ready for the nRF52 device family:
https://wiki.segger.com/Tracing_on_Nordi…conductor_nRF52
As the optimal trace debug software platform we recommend using Ozone as it supports the full feature set of the J-Trace probe including streaming trace and live analysis.
Best regards,
Nino