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This tree contains BLHeli code for sensorless brushless motor electronic speed control (ESC) boards.

To view and use the files, click the "Clone or download" button on this page,
and then select "Download ZIP" to download the repository to your computer.

For flashing, configuration and documentation, download the BLHeliSuite PC software:
From here.
Or for BLHeliSuite32 here.
Or the BLHeli_32 app here or from Google Play.

BLHeli was the first code developed, written in assembly for Atmel and Silabs 8bit MCUs.
Three versions of the code were made, for heli main motor, tail motor and for multirotor.
The code is open sourced under GPLv3.

BLHeli_S was the second code developed, written in assembly for Silabs 8bit MCUs.
BLHeli_S only supports multirotor applications, although it can also be used for planes.
For BLHeli_S, focus was on making throttle response smooth.
The code is open sourced under GPLv3.

BLHeli_32 was the third code developed, written for 32bit MCUs.
BLHeli_32 also only supports multirotor applications, although it can also be used for planes.
The code is closed source.

Documentation can be found here:
BLHeli Atmel
BLHeli Silabs
BLHeli_S
BLHeli_32

For more information, check out these threads on RCG:
BLHeli
BLHeli_S
BLHeli_32