Power control is now working. The command has been changed a bit, though.
It's a single commmand now, 'POWER', and it can be ON, OFF, or a delay.
ON forces the power output on, OFF forces it off. This lets you use the
high side switch to manually control a DC load. Setting it to a numeric
value makes the radio power control option function as usual, where it waits
the specified number of seconds for the radio to power up before
The Garmin protocol handler has been restructured - parts of it that were
executed in interrupt context got too big and slow and needed to be executed
in the main program loop.