I've cobbled together 232 control of an audio system with a series 4 processor where the only control interfaces for audio are web keypads viewed on the LHC+ app. I'm happy with the overall result but there is no LED feedback. I'd like to confirm whether the system is on or off with LED feedback on discrete ON and OFF web buttons. Is this something I can fake with a variable or condition? I believe the 3rd party device will acknowledge a good command but I'm not sure that the series 4 processor can receive that sort of info on the 232 port.
Any input is appreciated!