Acknowledge on data type alone, never on buffer id. A live Bebop 2 sends
DATA_WITH_ACK on buffer 126 and plain DATA on 127, the opposite of what the
buffer names imply, so requiring both to agree meant nothing was ever
acknowledged. The drone resent its state instead of continuing: 35 telemetry
keys where there should be 192, and a connect that took 4 s instead of 1.7.
Record argument-less events. Eight events carry no arguments and their
arrival is the whole message, including AllStatesChanged and
AllSettingsChanged, which mark the end of a state dump. Keying only by
argument decoded them to an empty dict and lost them.
Wait for those terminators instead of a quiet period. The drone streams
attitude at about 5 Hz throughout, so the link is never quiet and the wait
always ran to its timeout with a partial burst.
Also: preflight no longer reports ready when a blocking check has no data.
It answered 'ready' on an aircraft it knew almost nothing about, which is
worse than refusing to answer.
Ryan Malloy
169bc91a8f