Can you provide any more details on the I2C interface on Midea units?

I found some sparse documentation on Midea's (and rebadged units) Modbus-esque protocol over RS485 (aka XYE connectors), and I control it via an ESP32 on HA. From the indoor unit, the diagnostic data I could reverse engineer is limited to temp sensors (intake, indoor coil, outdoor ambient) and basic running modes. I believe the outdoor unit also has a modbus/485 that has more info, and obviously the signal wire passes some comms between the two, but Midea doesn't make this stuff public.