Yesterday I’ve received new flight controller for my Reptile X4R 220 quadcopter: Flip32 F4 from ReadyToFlyQuads. This is my first contact with STM32F4 based flight controller and I’m really looking forward to see if it really puts a difference comparing to F3 boards like SPRacingF3 I’ve been using last few months.
- STM32F405 CPU running at 168MHz
- MPU6000 gyro connected via SPI interface
- Integrated 1.5A voltage regulator
- VCP port
- 3 UARTs
Flip32 F4 (and Airbot F4 which is exactly the same board) is supported by Betaflight, RaceFlight (that due to some GPL violations I’m boycotting) and INAV (at the moment of writing this post INAV support is not complete) and REVO target. Well, basically, this board was designed based on OpenPilot Revolution stripped from radio modem, barometer and those JST connectors (pin headers rules!). There are some differences between Revolution and Flip32 F4 in terms of hardware (voltage regulator for example) or separate LED header (which does not work).
There are two “problems” I’ve discovered so far:
- Whole board is getting very hot. Looks like it’s because voltage regulator and battery monitoring are connected. You can not have one without the other even when you have BEC somewhere else
- STM32F4 does not have built in inverters. That means, S.Bus has to be connected to UART1, since this is the only UART with external inverter
Although I’ve been able to install it on Reptile X4R 220 already, I have no idea how it flies yet. Weather outside is very rainy…