How to send data from arduino to pixhawk?

Hello everyone,

Im Using 4 servomotors Dynamixel AX-12A, which work with the serial communication UART.
I can write and read servomotors positions using arduino uno.
I want to use this servomotors to rotate quadrotor arms.
when positions are changed, I have to tell the Pixhawk the actuals ppositions.

The quastions is : how to send data from arduino to Pixhawk?

You should have posted a link to whatever this Pixhawk is if you want help.

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