Hey, guys! I’m looking at the IKEA PM sensor mod but I also want to squeeze a mhz19 in there and both happen to connect over UART. So question is - can the wemos d1 mini support two UART connections (as I imagine one cannot be shared)? Is there an alternative small board (~45 mm long) that can handle two UART connections?
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Have a look above, someone has done it:
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Exactly the same here. Did you manage to get it working yet?
I think this shematic is very well done…
but maybe a found a mistake, according to datasheet and my voltage continuity meter the 5v and GND are swapped.
Here is my version (with some english led colors translation)
Here is the schematic i found for ES7P001 uC:
http://www.essemi.com/index/product/detail?id=41#http://www.essemi.com/index/article/download?id=413
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Probably the chinese website will be down in the future… so here is an excertp ( i cannot upload PDF due to community restriction)
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That Vindriktning thing is quite interesting.
I grabbed myself one approx. two months ago an now combined it with a Wemos D1 Mini and a BME280 breakout board to make some sort of outdoor weather station.
I really dont know how accurate the Sensor is (have nothing to compare), i modified it with some hoods so that the air will be sucked in from outside of the case and will go back outside when it passed the sensor.
We will so how it works out in the next couple of months.
I documented it a bit more in detail on my blog (unfortunately not translated yet but many pictures):
https://blog.sengotta.net/ikea-vindriktning-wetterstation/
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I really like your idea and solution how you retrofitted it, but I have doubts that the sensor was really designed for this sort of use. I mean environmental use, as outside. My main concern would be first of all humidity and condensation due to temperature differences.
And for outside I would rather choose a sensor which can measure multiple things like CO, CO2, O3, TVOC, NOx, VOCs, SO2 for better understanding what is the air quality outside.
I don’t know how is your place, but my place has terrible air during winter time. Fortunately there is a public station what can be queried through the Internet so no need for my own sensor set, and that one provides a great range of measurements.
Yep i know that that is really not the intended use for the Sensor, but hey was a nice experiment alongside with the 3D Cad and Printing. I will see if it works more than a couple of months.
There are public measurement stations in our city, but they are multiple kilometers away.
When the Sensor breaks down i maybe replace it with a Sensirion SPS30.
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LED controls progress? Night mode? Looks like the photoresistor does nothing…
As far as i understant from the schematic the PIN7 controls the GREEN LEDs and Pin3 controls the orange and red colors. I’am thinking how…maybe the uC ouputs low for turn on red and high for turn on orange? …but then… how does it turn off everything except green (high on pin7)
My idea is to chop off uC legs 3 and 7 but i don’t know what signal to generate to control LEDs individually.
Some suggestions? Thanks
Hey guys,
Thanks all for this great post and your valuable contribution. The day after I read it, I went to the local Ikea store, bought a sensor and succeeded doing the integration and setup with in 2 hours. I use the Esphome approach, and it just worked at once.
Most of the time I spent figuring out where and how to place the D1 Mini. Therefor I would like to share some of my pictures and ideas about that.
1- I placed the D1Mi under the fan, like others also did here. In order to save as much space as possible, I soldered the wires directly on the board
and now it fits perfectly:
Notice: Make sure to turn it the way I did, in order to avoid contact with that little skrew
2- I got the idea that I can use the Micro-usb port on the D1Mi to power the setup. So I made a hole in the back of the cabinet:
which is almost aligned with that on the board:
3- In order to make sure the board don’t move when putting the micro-usb cable in and out, I used hot glue to fix it:
Notice: I fastened the wires by cutting a track for them in the plastic like that for the fan. This insures that the wires don’t get in the way for the board and make it difficult to close the cabinet.
And that is it:
Now I can use the original Usb-C port, and the Micro-usb port to power the final product.
So I need not buy a usb-C cable but use a micro USB cable that I already had.
Notice: Another thing I also use an old 1A usb power supply which seams to work just fine. So I didn’t need to buy a new power supply neither.
The whole project cost me about 15$ 
Please let me know if you might have any question.
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Any idea if this would work in some sort of enclosure for outdoor use? I live in MN so it temps can range from -30F to 110F between summer and winter.
That’s what I use! mini-graph-card is amazing.
I don’t think so that it would really tolerate that range of temperature, but look at this:
Got mine working great, but I used a temporary long length of cable so I took it back apart, trimmed the cable and resoldered. As I screwed the case together I heard a small crunch… and a rattle. I reopened the case and found I’d put the ESP8266 into a position where the ceramic wifi antenna was wedged and as I screwed it tight the it shattered.
Never mind, I went to go swap it out and in doing so ripped one of the pads off the Vindrinktnings PCB…By this point I thought my luck cant get any worse and tried to use the trace at the top of the board…which also ripped off.
I have 4 more that have arrived so this time around Im doing it slightly differently. I bought 4x 5way picoblade sockets, and 2x 5way picoblade double ended cables. My soldering is far from the best but I managed to solder the picoblade socket to the top of the board. When the cables arrive I’ll be cutting them in half (I did look at crimping my own cables but when I saw the size of the pins I decided against it) and soldering them to the ESPs and just plugging in. No more damaging pads and track for me
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Can you share some links where you ordered those from and what exactly?
The sockets were from Ebay - https://www.ebay.co.uk/itm/203317688275 - and the cables are from Farnell - https://uk.farnell.com/molex/15134-0501/cable-assy-5pos-rcpt-rcpt-100mm/dp/2913936
They are standard 5 way Molex Picoblade items so you might be able to shop around and get them cheaper.
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So you’re powering Ikea PCB and sensor through Wemos 5v pins right? By connecting to the same Ikea PCB pins as in the main guide? I was wondering if this is safe and if so that means the whole system can be powered either via MicroUSB on Wemos or USB-C on Ikea PCB.
Can anyone confirm? I wouldn’t want to frymy sensor
Okay, I have to admit, the fan is starting to drive me crazy. What’s the current best practice to rewire the fan to run on constant power while using the D1-mini mod? Snip the fan cables, then hook up red directly to the 3V3 pin and black to the G pin of the D1?