Responding to my own post…
I see from the traffic monitor, that when I try to turn on an output, it sends a command like:
2 To ID:08.9D.C3 flags:0F cmd1:48 cmd2:1
According to the EZIOxx docs, shouldn’t cmd1 be 45, not 48?
Nevermind. It looks like cmd 48 provides a bitmask to enable multiple outputs at once. The bits set do seem to correspond with the individual output I want to control.
I’ll keep digging.