Updating of firmware of APM 2.6 procedures

I have read through the wiki, and could not get information on what procedures to follow to update the firmware on the APM with a newer version, regarding the following:

Must everything be disconnected from the APM? I have read of usb port burning
What will happen with the current parameters and calibration of equipment with updating?
How can I backup the parameters and calibration to load on the new firmware?


Unless your PC has robust USB ports or you are using a powered USB Hub, I would recommend detaching components from the APM to reduce the electrical load during programming.

And what happens to the calibration, setup and parameters?

After updating the APM firmware, hook all of the components back up and proceed to do the calibrations using the telemetry radio.