52840dk Segger debug exception when using softdevices.

[pkoenig]

Debugging in Segger serial example from mesh

It runs and responds to commands, but when paused or hits breakpoint - single step or continue gets to address 0xa60, continue logs the message:

app_error_weak.c,   96, Softdevice assert: 154516:0

Are there some required debugger setting whne debugging with softdevices?

I was debugging sample project without the softdevice without problems - possibly there is another issue.

[Igor]

Can you please post a stack trace.
It would be also very helpful, if you would mention your SDK & SD version.

[pkoenig]

Igor, sorry, it implies latest versions (released to the web)

The 840DK ver 1.1.0

Included two screen shots: after stopping on breakpoint, and after continue. Do not know if you could see graphics in the post, so adding those two pics as one zip.

If I do single step in asm mode, it debugs correctly, but stepover in source is causing this exception.

If you step in asm mode, you just issue single step to the debug logic on the core, with source stepover, most likely they insert temp break at the step target address, then run. Any run is causing probably this exception - possibly caused by pending interrupts in the exec pipeline.

Do you know if there is a way to show low level debugger operations on the JTAG interface?

Thx, Piotr

Downloads.zip

[pkoenig]

For reference I am sending the current binaries I am using for the project "serial" from the mesh sdk.

If you set the breakpoint on main.c:155, run,, first src stepover is OK, second stepover generates the exception.

I am using Segger 4.42, with latest firmware on the 840DK

Calls to my code should be disabled in this project.

I will try 832DK with older firmware.

serial.zip

[pkoenig]

For reference, here how I have unzipped SDKs on my HD, and serial example is in its original "mesh sdk" location:

[Edvin]

Hello,

If you break during the debug session after the SoftDevice has started, it will assert later. This is because the SoftDevice will miss some time critical events where it was supposed to use the radio. So you can use breakpoints to see what's happening for a few steps, but when you step out of that function (or possibly before) then the softdevice will assert. 

What you should do is to use the breakpoints to check certain things that you want to check, and then you must reset the application.

Best regards,

Edvin