Arduino nRF24l01 (using RF24 library) KN protocol (WLtoys) RC-Receiver, receiving signals from WLtoys PowerStar X1 transmitter
I used this lib together with the stm32duino library and a modification of RF24 library if you want to use it just with normal Arduino uncomment neccessary lines in the header file.
For Arduino Uno/Nano
https://github.com/TMRh20/RF24
For STM32
https://github.com/rogerclarkmelbourne/Arduino_STM32
https://github.com/chacal/rf24_stm32