I would like the ability for two way RS232 support for hi fi/home theater, etc. devices that support it (I say “etc.” because hi fi/home theater is my main interest).
I see in your videos a volume up/volume down command with a bar graph in response. This is obviously not possible with IR commands, at least not honestly.
I use an Oppo UDP-201 disk player and a Parasound P3 analog preamp, both of which have DB9 RS232 connectors in back and both of which have a table of commands and codes that can be sent that way, as well as codes for status that can be read. If there is insufficient interest for a piece of hardware, I’d be perfectly happy with code that can be run on e.g. a Raspberry Pi with serial port adapter. I know my way around simple C, Java, Perl, etc. programming but am by no means a programmer, so it would take me a while to come up with something like that.
IMO this request is by no means off the wall. Much professional a/v equipment, as well as some consumer, still uses Rs232. A lot of Parasound equipment does, including the “Z” series. At the university where I work we use Extron controllers (which can be bought by anyone, as opposed to Crestron, available only to professional installers) to control projectors and other equipment, using RS232 wherever possible. Power on/off status is always good with projectors (Mine doesn’t have RS232, or even discrete power on/off, but my next one definitely will).
I know the latest and greatest equipment uses Blue Tooth or IP (including my Apple TV box), but a lot of us are still using older stuff. The Oppo disk player actually does offer IP control, via the “Media Control” app. As pointed out in the blurbs, I am not fond of fumbling around phone apps to control various HT equipment, so don’t use it much, but it does read back track info, etc. It may be the preferred way to integrate the Oppo with YIO. Still, I would not expect that to work out of the box either. (How could it “learn” IP codes, let alone how to read back status?)