@status current Introduced in 2.9.0
port_nr: valid values are only 0 and 1 on radios that have SWSERIALPOWER defined
0 - first serial port, e.g. on TX16S AUX1
1 - second serial port, e.g. on TX16S AUX2
value: true for power enabled, false for power disabled.
nil serial port power control not available