The APM takes data over a protocol called Mavlink and Xbees are one of the supported (and cheaper) communication methods. Mavlink was designed to be a very fast data protocol as to allow for actual live feed of data from fast moving vehicles or sensor arrays, thus it requires a high nitrate of about a 11000 baud rate. The Xbees are capable of that but are set to 6200 baud by default. Thus we need to change the baud rate in the XCTU utility through the terminal. This implies reflashing the firmware to the Xbee (I'm using Pro modules but its the same for standard series 1 modules).
The Xbee pro modules run over 900mhz radio waves. Thus they do not interfere with the main 2.4Ghz control line of the Hexacopter. On the other hand they might disturb the 860Mhz radio signal coming from the Video receiver. I'm going to need to mess around with cloverleaf antennas and the channels used on the two devices later.
Comming back to the main problem, in order to connect the Xbee to an X86 PC, an adapter board must be used, I chose the once form Paralax as it was good quality and a proven board.
What becomes immediately obvious upon examining the USB adapter is that there is no reset button present. This is a major problem as the Xbee modules will be in a soft-brick after flshing, meaning that I will have to reset the xbee while powered. To do this, I have to "short" the RST pin to one of the ground pins. For some reason, the Xbees are not posting at all after doing this, possibly being Hard-bricked. I will have to look further into this but I am not making it a priority as it is more of a side/safety feature that can be added anytime later.
Once functional it will enable me to see live telemetry from a laptop as well as control the APM 2.5 through something like a joystick or a gamepad, thus making it far more accessible for beginners, and funner with something like the Wii mote ;)
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