Beside mbed online compiler and closed source Keil, What is the best open source IDE for Arm software developer ?
Without claiming to be the absolute best, if you are interested in an Eclipse based open source solution, you can also consider the GNU Arm Eclipse plug-ins project, it covers most entry level use cases, from project creation to debugging. More advanced debugging features, like peripheral register views are currently work in progress; simple tracing is available via a semihosting/SWO console, more advanced tracing features are planned for future releases.
If you have further questions, please don't hesitate to ask.
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