# Trying to understand the source code (Pixracer)

**URL:** <https://discuss.px4.io/t/trying-to-understand-the-source-code-pixracer/687>\
**Category:** Uncategorized\
**Created:** [July 11, 2016, 4:13am UTC](https://discuss.px4.io/t/trying-to-understand-the-source-code-pixracer/687 "2016-07-11T04:13:34Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Arnold](https://discuss.px4.io/letter_avatar_proxy/v4/letter/a/3d9bf3/32.png) [@Arnold](https://discuss.px4.io/u/Arnold)\
**Post date:** [July 11, 2016, 4:13am UTC](https://discuss.px4.io/t/trying-to-understand-the-source-code-pixracer/687/1 "2016-07-11T04:13:34Z")

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Hi

I ordered a Pixracer but in the meantime I’ve been trying to understand the code. There is a mc\_att\_control module and there is also another one named mc\_att\_control\_multiplatform.

What is the difference between these two and which one will get installed in my board?

How will QtCreator or whatever IDE I use know what to actually upload to my board? Is this what the CMake files take care of?

Is there anywhere I can learn more about how all of this works?

Thank you

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**Author:** ![bkueng](https://discuss.px4.io/letter_avatar_proxy/v4/letter/b/2bfe46/32.png) [@bkueng](https://discuss.px4.io/u/bkueng)\
**Post date:** [July 11, 2016, 10:52am UTC](https://discuss.px4.io/t/trying-to-understand-the-source-code-pixracer/687/2 "2016-07-11T10:52:58Z")

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Hi Arnold

Welcome to PX4!  
I don’t know about `mc_att_control`. The included commands are configured via cmake. For pixracer it’s this: [https://github.com/PX4/Firmware/blob/master/cmake/configs/nuttx\_px4fmu-v4\_default.cmake](https://github.com/PX4/Firmware/blob/master/cmake/configs/nuttx_px4fmu-v4_default.cmake)

Documentation is under [http://dev.px4.io](http://dev.px4.io) and the source code itself.