Thanks, I had a closer look at your example photo and I can now see the S21 port on my unit’s PCB. Now to find the time to get a custom solution sorted. Out of interest, what made you go for the custom board solution instead of buying a BRP069B45 unit, for example? I have no idea which BRP069B4x units are compatible with my FVXM-A because the Daikin website just says the WLAN adapter is “built-in”. 
Hi, i am using 12 indoorunits one old BRP069B45 is between 60 - 100 €, only the cable to connect is arount 18€. now I build everything by my selfe and withe the correct jst connectors i am at 120€ for all untis. i started with one to check if have succes, now i started the “rollout” 
the next reason is now i have 100% local controll and don´t need any daikin app for setup. f* o* daikin! i have also the “build in” Wifi adapter. it is the red marked chip.
in the side of your housing is drawing of your “circuit diagram”. in my test unit i am using both wifi controllers. now in the Onecta-APP i can see only the states off the uinit, they recognize that i am using a controller. when i finished all units i will disconnect the original from wifi.
my test unit is a ctxm16r2v1b. I claim they will not reinvent the “S21” bus protocol for every indoor unit
I assume you had to solder the other ends of the wires to the ESP32 dev board? If so, which pins go where?
i draw a little circuit diagram how i made it (quick and dirty)
Adrian shared his PCB Project also.
my last missing pice is a little “S21-Shield” for the dev board. drawing and ordering the PCB is my little “easterproject”. i will share it when it´s done. my prototype ist running on a breadboard.
I’m happy to buy the prebuilt PCB for simplicitiy sake (also as I only need one of these), but nowhere does it show a picture of the cable! I know it says the wiring for that is the same as an official S21 cable but there’s no pictures I can find for that either. It might be straight pin-to-pin but I have no evidence for this. 
Hi there, I am considering buying a Daikin Fit + central unit with One+ thermostat to go with it.
Is the current integration working with it or still an issue with their closed system?
Found their openapi here Daikin One Open API - Examples
My other option is a Chinese Gree equivalent system with an ecobee but I am unsure if the quality is comparable. 10y warranty vs 12y with Daikin and the decibel levels are somehow in the same ball park.
Thanks in advance.
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This integration work fine with BRP069C81, not fast as other devices but the request unfortunately have to do the long way round.
Is there anyway to determine which WIFI adapter will be shipped?
I’m interested in a FTXM 20R Prefera
Maybe? It seems to depend on region. All my Stylish units have “B” controllers, my Perfera has “C” (UK). Others have said their Stylish units have “C”.
I just realized that they just changed the AP SSID to hidden. If you run an wifi analyzer you’ll see the hidden networks…
Meanwhile, I’m using the rospogrigio cloud integration and it works great.
You can add B-series wi-fi adapter that supports local API to your Perfera units. I did it for my Perfera floor standing units already.
Where did you buy the connecting cable and adapter?
The cable - from Daikin, the installer bought it for me. The adapter - I had it from before but it’s available either from Daikin and from eBay/marketplace/OLX.
That’s nice, I’ll see if I can make the same. Is there any way to disable the builtin AP in the board?
Pull off the connector from the board. But anyway they can work simultaneously - if you add both adapters to Onecta - the AC will appear twice in the app. You can than remove the old adapter one from your Onecta account - thus way it will remain in your LAN but will not be connected to your cloud account.
it is. I’m controlling my splits with simple dupont wires from a ESP8266 to the S21 socket.
Hey, that’s really cool, can you share the code for this?
oh, well, let me see if i can remember how to put something on github, never thought someone could be interested 
I’m very interested! Because I won’t need to buy an official Daikin adapter and cable this way! Can you share the wiring scheme as well? I believe there’s loads of people interested in that!
oh well i just used an esp8266 mini, a mini560 step down, a mini breadboard and 5 dupont cables (one is not used) male to female. Far under 10$.
This also fits inside the units:
The socket is in the specs described by this project
but obviously i can speak only for my units model (FTXSxxG). I’d try with a tester to see if yours is the same, maybe you’ll need also a level shifter for serial lines.
i also freely took part of this code so kudos to them
I’ll try to post my code this weekend on git. The integrations is done fully with mqtt…
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