I first created a post about this in the Arducopter 2.x subforum but now I've updated to the version 3.1 firmware but I still have this problem.
The problem is my bluetooth telemetry which is connected to UART0 on my board. The BT module is configured to the baudrate 115200 and it works as long as usb is connected to my computer. I read in this thread http://diydrones.com/forum/topics/apm-2-6-schematic that the APM changes state when it's connected via USB or powered by lipo. When it's powered with a lipo (airborne mode) then UART0 is configured to use baudrate 57600. I've tried changing the bluetooth module to baudrate 57600 aswell but then it doesn't work neither in USB or in "lipo" mode.
I've also tried connecting it to the telemetry port with all the different baudrates 9600-11520 but that doesn't work.
I really appreciate any feedback on this.
Replies
Use UART1 it does not change. Set both devices to whatever baud rate and Bob's your uncle.
Isn't UART1 used for GPS only?