Modifying framework files


I am using a Teensy 3.2, and I am trying to test some modifications to its core files, that are part of the framework-arduinoteensy package.

I am using atom, and I am on Mac OS X El Capitan.

I am trying to do this by modifying the files in ~/.platformio/packages/framework-arduinoteensy/cores but when I compile, it does not appear that the changes are taking effect. I have even tested by making some drastic breaking changes, but my code will still compile just fine even after doing a clean build.

Am I missing a step, or some cached things that are preventing my changes from propagating? Is there a standardized way to create a development version of a package, to test with that I should follow to do this kind of thing?

Thank you!

Turn on verbose mode with pio run --version to see where are files located.


this is an old thread, but I cannot figure out where to find the source files. With -v I can find the source for the libraries I installed, but not for the core. I would like to modify one of the Arduino Framework files, wiring.c. I can find the .c.o file, but how can I modify the source code?

thanks in advance!

Maybe PlatformIO only recompiled that library. Make sure to clean the project before recompiiling. Do pio run -t clean && pio run -v, there you should find the core files. They should be one of the framework-arduinoXX packages in /home/<user>/.platformio/packages/.

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thanks @maxgerhardt! That was easy and worked :slight_smile: