Hello diydrones community,
I recently got into quadcopter flying with a Hubsan X4, now I want to build my first own quadcopter. This week I received all the parts that I need, based on a DJI F450 Flame Wheel ARF kit.
After reading all about the different microcontrollers and the PX4 and Arducopter firmwares, I found out that the STM32F4Discovery board runs the PX4 firmware. I have that at home and thought I'd give it a try. Because quite honestly, I can't afford a new Pixhawk controller, it costs around 250 Euro in Europe and most places don't actually have it available at the moment even at that high price. I followed the official pixhawk.com instructions here: https://pixhawk.org/modules/stm32f4discovery
Now the PX4 firmware is running successfully, the Nuttx OS works exactly as described in the guide. However, the microcontroller is not recognized by Mission Planner - I don't think it can run the Arducopter firmware anyway. Thus, I assume that Qgroundcontrol should work. It recognizes it as "PIXHAWK" and says it is connected in the upper right corner - but the interface doesn't reflect the status change and it looks as if it was not actually connected.
I tried out the firmware upgrade in Qgroundcontrol, the firmware files are provided here: https://pixhawk.org/firmware/downloads
All three can be installed, master, beta, and stable, but none seems to boot. Flashing is successful, the device restarts and the bootloader LED blinks for a moment, indicating that Nuttx will be loaded now. But then the LED turns off and nothing happens, the serial port via microUSB does not show up. I assume it fails to boot.
Now, I have seen videos on Youtube of quadcopters flying with the same Discovery board, but other than that there are no further instructions anywhere. Boot issues? The board is not mentioned in any forum (this is why I posted it here, since there is no appropriate subforum...), there is no guide about which pin is for which input/output.
What am I doing wrong? Your help is very much appreciated. Thank you!