Segger J-Link Software​

Segger provides the basic J-Link Tools Suite, and more elaborate applications like Ozone, a graphical debugger.

​Most of the utilities support Windows, macOS and Linux.

J-Link Tools Suite

The software is very standard. Uploading binaries to the MCU is carried out with JLinkExe, and debugging relies on the classic server-client scheme. 

For the GDB server, I first tried OpenOCD but faced some issues. Everything was solved with the supplied JLinkGDBServer. 

I set the port to 3333 to comply with the OpenOCD standard.

​The server JLinkGDBServer runs on a first window on the left and the client arm-none-geabi-gdb on a second window on the right.

Ozone

Ozone is a free graphical debugger.

One single window displays multiple views.
  • On the left, the list of functions and the console;
  • On the centre, the code being debugged;
  • And on the right, the disassembly, the registers, the watched variables and the call stack.

Multiple additional views are available, like the list of breakpoints, memory, local data, and even graphs. Views can be re-arranged. 

On macOS, use Ozone v 2.22o or later with J-Link v 2.12i or later, as previous releases may crash.
Click to enlarge.
The configuration wizard consists on 3 screens.
​
  • The first screen asks for the device, here the generic Cortex-M3 for the Arduino Due.
  • The second screen defines the interface (JTAF or SWD) and the speed.
  • The final screen selects the .elf file.

The configuration can be saved as a .jdebug file for later re-use.
Counts, conditions and actions can be set on the breakpoints. I haven't figured out how to use the Trigger on change.

One limitation: the console and the pop-up message display the text entered, not the value of the variable.
In case the program has been modified by another application, Ozone prompts a message and asks for updating it.

​Conclusion

​The software provided by Segger is fast are reliable, along with well-written documentation. The Ozone application offers a decent graphical interface for debugging.

​Support is very responsive and provided through the Segger forum.

I've explored debugging against the Adafruit Feather M0, Adafruit Feather nRF52, Arduino Due, Arduino Primo Core boards with the Segger J-Link.

Pros

  • Software suite for Windows, Linux and macOS
  • Extensive documentation

Cons

  • Some issues with OpenOCD

Wrap-Up

  • Reliable software and extensive documentation  

Links

​Posted: Aug 22, 2016
Updated: Sept 08, 2017