µVISION DEBUGGER: "Trace HW not present" using J-Trace on Cortex-M7

Information in this knowledgebase article applies to:

• MDK v5.x
• Segger J-Trace or J-Trace pro debugger
• Cortex-M7 devices

SYMPTOM

I'm trying to enable the SWO trace or the ETM trace in MDK µVision for a Cortex-M7 based target device using a Segger J-Trace pro debugger. But as soon as I enabled the trace setting in MDK µVision, I cannot start the debug session. The error "Trace HW not present" is always shown up. But I'm sure the trace HW debug unit as well as the corresponding 20-pin trace debug port interface are available on my target device. What has caused such an issue?

CAUSE

Unfortunately so far the JL2CM3.dll JLink/JTrace debugger driver DLL from Segger used in MDK µVision doesn't yet support the trace debug functionality for all Cortex-M7 based target devices. Flash programming and normal debug functionalities are not affected by this restriction, but as long as the trace debugging is enabled, such an error "Trace HW not present" will show up.

RESOLUTION

So far there is no workaround solution for such an issue. More info will be given under the collaboration with Segger.

STATUS

On the other hand, the JLink/JTrace driver used in µVision does support SWO trace or ETM trace for Cortex-M3 and Cortex-M4 based devices.

Last Reviewed: Monday, April 1, 2019