LED ring for CrazyFlie2.1bl brushless drone

[RPeterTech]

Hello, I need RGB LED light for our CrazyFlie 2.1bl drones. My first idea is to figure out how to make the LED ring deck work with this brushless drone. As I see, the problem is DMA1 Stream5. It conflicts with a motor control. Has anyone some idea how can I avoid this DMA channel when communicating with LED ring deck? The WS2812 protocol is very time-critical...

[tobbeanton]

There is a workaround to use a analog motor signal protocol that is documented here. Use a late build though since this PR is needed to configure the ESCs afterwards.

[RPeterTech]

Thank You for your answer!

Unfortunately this doesn't work. The modified firmware doesn't do anything with the downloaded ESC firmwares. The boot signal played correctly with the new ESC firmware, so the flashing is OK. The modified cf21bl firmware also OK, after flashing an original drone (original ESC firmware) with the new cf21bl firmware, if finishes working with motors, so the protocol is obviously changed. But it also doesn't work when the cf21bl AND the ESC firmware is modified too (ESC is the recommended 48kHz type, cf21bl is OneShoot125 configured.). No arming, no flying, no any rotor moving, only the boot signals. Also no moving with the ESC flashing webpage's motor control test.