APM 2.6 interface usage

Our group just has started to use APM 2.6 and
we are going to make communication between APM 2.6 and another device but haven’t decided which interface to use: I2C, UART0 and UART2.
Please advise what is the best choice and why?


What is the project? APM 2.6 is very nearly out of everything. PIXHAWK might be the better choice.

As to which bus - I’m sure it depends on the application. For simplicity and familiarity I would probably pick uart, but I’m no expert on the hardware side of things.

Thanks for the advice about PIXHAWK.
UART is the right choise, but I’m not sure that UART is not used for other purposes by APM software.
Is there any unused UARTs in APM 2.6?