A while ago I received an "Attach Demo"-Board consisting of an FRDM-KL26z, a Battery-pack (FRDM-BATT) and a 2.8" Touch-screen. At that time I already made some simple implementations of the command controller for the Crazyflie on an FRDM-KL25z Board powered by USB. So the Attach Demo with its Battery seemed a good Base for some further tests. For that, I removed the Touch-screen and added two joysticks (https://www.ghielectronics.com/catalog/product/299) as well as an OLED (SDD1306) and an NRF24-Modul that I used in other Projects.

After a little programming I had a cheap working controller for my Crazyflie. Unfortunately this fast solution didn't let me log parameters such as the battery-state and also didn't let me get or set other parameters such as the led-ringeffect. So further investigations had to be done to know how the Crazyflie works. After studying the source-code of the Crazyflie a crazy idea jumped into my mind: Why not just "invert" the source of the Crazyflie? So lets try that...