I am sure this question may have already been asked however, after reading up a bit I would like to know the difference between the mega 2560 and the APM2 plateform? The reason I ask is after looking at the schematics I don't see a lot of difference. I will assume the outputs are hooked to the digital pins that have PWM capability. I am still researching the inputs.
The reason I ask this question is I have a bunch of Mega 2560's floating around along with several GPS units and various other stuff such as Compass and Accelerometer Module and 3-AXIS Gyroscope. Is it feasibly possible to use these devices I already have and incorporate Arduplane 2.x software to it. It would be nice to use the stuff I already have instead of spending another $179.00