Hi all, I saw your thread on tweakers.net and am very interested in getting this running @ my home as well (Mitsubishi Ecodan owner). Currently I'm running a WeMos D1 to force a 10 minute duty cycle on the thermostat input, so adding this to get readings from the heatpump in my OpenHab installation would be very nice :-)
@BartGijsbers any suggestions on where to get the level shifter? I have a lot of stuff lying around except for that. I would like to play around with your code to implement the homie standard (https://homieiot.github.io) so compatible controllers like OpenHab can automatically recognize it.
Hi @BartGijsbers , I've built a board based on a ESP32 just like you to get started :-) I wanted to double check the pinout on the Ecodan, do you happen to have the color/pinout mapping? My cable has the following cables: red/brown/orange/yellow/green. I've read somewhere that pin1 is 12V?
Also, I'll fork your code on Github to make some changes. I'm using platform.io and it's quite picky regarding C-style forward declarations (whereas the arduino studio works around that in the background).
We found some more details relating to the ForceDHW and the use of set command 0x34 (byte0). Think you have to set byte1 to 0x01 (flag?) and then byte3 : 1=Force or 0=Normal.
I found this too, bytes 1 and 3 set, I couldn't turn it off though. I also tried byte 1 to 0x01, and tried setting byte 4,5,6,7,8,9... etc in sequence, but didn't seem to find anything