I see a lot of "!TSF" and "NACK" which seems to be radio communication problems.
That's MySensors related and can be related to many things, from soldering problem to power / capacitor issues.
In MY_DEBUG mode you should see your temp/hum printed on serial every ~15s so there is something wrong there, either wiring or a code issue.
Ty with the example included with the library "i2c_SI7021.h", without any MySensors related stuff, to see if your sensor is detected. You should see temp/hum on the serial.
Added sketch, which also supports an additional mini PIR sensor. It's what I needed, you can comment to #define out.
Also changed the regulator to a smaller one, which supplies up to 100 milli Amp, which is plenty enough. That way I can keep the circuit smaller on the PCB. Which allows me to create a smaller housing.
This should work with Domoticz, it's what I intend to use with it. I've received the boards from China and I'm currently working on a version 2 of this board. There are some errors in the design of version 1 that I need to get out. New version will be up shortly.
To provide a large enough pulse to drive the ceramic transducer , you need a lot of energy, so they pump up the 5v with an inductor/transformer to provide a high voltage pulse. This is 60v or more…
The more Energy you produce the farther the pulse will travel….
Everything thing else on the board run at 3.3 to 5V.
Add a large Capacitor of 100 µF are so between the 5v and ground on the device, this may clean up your problem.. Some CPU modules just can’t supply enough current quick enough that’s needed when the pulse is triggered.
These are very inexpensive device, we’re luck to see them work at 1/2 the spec range.
