APM 2.6 is Arduino Compatible!
what does that mean?
thanks!
It means it has an ATMega2560 IC with a bootloader.
However from what I recall the actual APM software doesnt use the normal Arduino IDE it uses a modified version.
I'm not sure if this for uploading, I suspect its to allow them to do things with the processor that the Arduino doesn't allow you do to, or perhaps removes unwanted wastes of memory like the Serial buffers
You are better off posting to the DIY Drones for full details