Another screenshot where I've scaled up the blue probe:
Your MRCOOL unit uses Midea's single-wire communication bus on the "S" terminal, which is different from the two-wire S1/S2 communication bus that this project monitors.
Because of that, a Waveshare RS485 adapter won't be able to communicate with your system. The communication method used by your unit is fundamentally different from what this project was built for, so the hardware and software aren't compatible.
I think part of the confusion may be my fault. Earlier in the project I referred to the S1/S2 bus as "SComms," but that's just a name I came up with and isn't an official term. Ive been trying to change all SComms references since learning about your "S" wire communication.
edit: I've been unable to edit the title of this thread but I flagged my first post and asked if maybe a moderator can change it.
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I see. Completely spaced that the wire I probed with the blue probe is the neutral.
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Finally got XYE EEV, t2, and t2a added to Home Assistant. Its not perfect but its added. Pics of what I'm decoding. All images should line up with time. 4:30 starts a cycle and stayed in low load with 2 oil return spikes, 6:00 the Room Temp jumped so the system went into steps looking for best high load position. Then around 7:30 unit turned off after Room Temp went below Target Setpoint.
First 3 are XYE sensors. I have T2 with S1S2 but I figured since XYE has T2 and T2B ill add both for validation. The rest are S1S2 sensors. I do have a hand full of other sensors Ive excluded.
Outdoor EXV and Indoor EEV
The temps. I really need to buy some temp probes to fix some decoding.
Yellow line is the actual thermostat outdoor temp reading which is rounded to get to .5°. Blue is the S1S2 single byte outdoor temp not rounded. Green is the outdoor temp byte with a second 4 step 1/4° modifier. They like there outdoor temp precision.
This gets confusing especially with those steps. All 3 are from byte 17 on 3 different frames. The byte that I believe doesn't belong in the payload.
Then there's these. Blue, brown and red are raw numbers. Green and yellow are decoded to go negative when the bytes rolls back to 255 down.
I'm now wondering whats in the HAHB line vs the XYE...