In particular allows the use of the gimbal using PROTOCOL2 attached to a
DroneCAN bus. ArduPilot 4.6 is recommended due to the timeout bug causing
message sends to fail regularly on 4.5.
Tested also that misconfiguring the CAN bus will result in the driver
failing to start, though the error message will be less specific.
DJI R SDK version 2.2.0.5 released on October 30, 2020 added CmdSet and
CmdID bytes to reply frames before the data segment which need to be
skipped when parsing replies.
Tested with gimbal firmware 01.04.00.20 and 01.05.00.20 (latest version).