KY015 - Humidity and Temperature 2.0.x

[sincze]

Hi

After starting with MySensors 2.0.x I did not find an example for my KY015 Humidity and Temperature sensor.
(maybe have to do a new git pull first....)

So i created one myself that does work nicely with my still 1.5.4 serial Gateway at the other end of the house.
Example: https://github.com/sincze/mysensors-2..0.x-temperature-humidity

Maybe somebody else is happy with it as well.
I'll be adding a doorsensor alsol so I can measue temperature / humidity in the room as well as turn on the lights when the door is opened.

[mfalkvidd]

@sincze great work, thanks for sharing.

MySensors has an example for DHT sensors, which seem to be the same as KY015? The example is available at https://github.com/mysensors/MySensorsArduinoExamples/blob/master/examples/DhtTemperatureAndHumiditySensor/DhtTemperatureAndHumiditySensor.ino

Examples with dependencies on external libraries (DHT in this case) are located in a separate git repository to not cause conflicts with other libraries.

[sincze]

Hahaha
I knew it ;-) you guys would be faster.

Instead of checking the regular website:
https://www.mysensors.org/build/humidity

I Should have checked your latest commit ofcourse.
https://github.com/mysensors/MySensorsArduinoExamples/blob/master/examples/

[mfalkvidd]

@sincze yeah, it is a bit confusing with the old examples on the build pages. Hek is working on a new site which will make updating much easier. I think the problem is that the weather has been too good for indoor work the last weeks ;-)

[TheoL]

Since we're on the topic of Humidity sensors. I'm experiencing a lot of troubles with the DHT family. Nodes work for a period then suddenly stop reporting temperature of humidity or both. Or in some cases the Node crashes.

Does anyone have a decent alternative that also will work outside? Meaning can handle temperature below zero and above 30 degrees Celcius?

I've tried everything I could find about DHT. But to be honest. I'm through with the DHT.

[mfalkvidd]

@TheoL Si7021 was praised when the sensebender was built.

https://forum.mysensors.org/topic/3801/witch-temp-hum-sensor-is-best-to-use-for-battery-powered-sensors/2 has a link to a comprehensive study

The DHTs are cheap and measure temperature which is something everyone can relate to. So they are a great "gateway drug" for attracting aspiring MySensor fans. But besides that they seem like crap :) I see that you are ready for the heavier stuff ;-)

[TheoL]

@mfalkvidd It's not perse the DHT itself. I've tried several libraries. But most of the cause the arduino to stall even if I haven't hooked up an DHT. Which I find strange.

I ordered a couple of si7021 sensors and experimented with them. They are great, except for the fact that they are 3.3V and you'll need a level converter if you want to connect them to a 5V arduino. That's probably the reason why most people who begin with the Arduino don't want to try them.

Also the DHT seems to be cheap but on aliexpress an si7021 costs half the prize of a DHT22. But it is has similar accuracy. Would be nice if one of the hardware experts could make a breakout version with onboard logical level converter. So that you can connect it directly to a 5V Arduino. Might save a lot of people who start with the Arduino a lot of trouble and DHT frustration ;-)

[Boots33]

When I built my WeatherDuino weather station I used a Sensirion SHT11. It has been going well for a couple of years now.

[sincze]

@Boots33 Very nice project. I like it. I'll look into the Sensirion SHT11 as well thx for the tip

[Yveaux]

@sincze si7021 is a clone of sht21 (sht11 is older and protocol is incompatible)
I have experience with all of these sensors and would just go for a si7021 on a cheap Chinese breakout.

[TheoL]

@Yveaux I hooked one up to day with a logical level converter. Maybe the converter is broken, because the sensor worked on a pro mini 3.3v. Have to postpone this for a while. Couple of busy weeks ahead.

[sincze]

@Yveaux Ali E... here we go....
With all the free tips the pile of spare parts starts to grow ;-)

A well ... got to have a hobby.
Tnx for the tip.

[TheoL]

@sincze Is it just me, or do you guys also have to sign for each package you receive from China? I think it's a new regulation in the Netherlands. Oh well it just means that I have to go to the postal office once a week to collect me yellow envelopes ;-)

[Yveaux]

@TheoL few weeks ago I got a packet the postal office even didn't try to deliver. Just got a message I could pick it up at the nearest pick up point.
Happened only one though...

[sincze]

@TheoL We have a nice receptionist that collects and distributes yellow envelopes.
If sender in China used POSTNL that means you have to walk to the post-office. ..

[TheoL]

@sincze I've noticed that I only have to sign with PTT deliveries. But it's okay the girl behind the postal office counter is a real beauty.

[tlpeter]

Two days ago i got two through the mailbox and two at the postal office.