Hardware

@bgunnarb nevermind... but still finding the best way how to wire it and power it. Readings are inaccurate :(

@MikeF Great, I just found the same unit right before your post. Seams to be the best option right now.

Then you have to modify it a bit. I really think you should try this yourself to learn how it works. Have you read the relevant API pages on the main site? Did you get stuck somewhere?

@TimO Great, thank You!

If I remember well there should be some modbus libraries on github

I think it's not worth spending time on a half working solution when there is a working one that's very cheap

@gohan Thanks for info.

@dbemowsk said in Problems with an SI7021 temp/humidity sensor: @Yveaux So I tried that library and it worked. Thanks for the help. Now I just need to print an enclosure for the thing. Great!

@mfalkvidd Thank you, this is worth checking! regards,

@Aron-Sjöberg Great switches, I thought these went out of production in the 60'ties :) As you are going for a battery powered solution a good starting sketch would be the motion detector. Just replace the motion sensor with the switch and you are almost done. The switch will probably need some debouncing. Add a ``sleep(100)``` to avoid retriggering. If you want to use a momentary switch you need a variable to save the last state.

Not really, I haven't used them yet. Remember that you can use the M0 as sensor node.

@tomasandersson Have a look at this thread. I think it contains the answer on your fixed ID (children) question. https://forum.mysensors.org/topic/4834/unique-id-value-ds18b20-temperature-sensors I personally used the sample programs as provided with the MySensors lib with succes the get the DS18B20 onewire working. A resistor 4k7 from +5VDC to the middle pin of the DS18B20 connected to D3 from the arduino and both outer pins of the DS18B20 connected to GND works perfect for me. BR, Boozz

A supercapacitor with a small solar cell would be interesting - does anyone have experience (3.3/5v size of capacitor, solar cell, etc)?

Wow, i did not do this to my digital weight scale. You did a great job here

I found the problem: https://github.com/LowPowerLab/SPIFlash/issues/16 The sketch I used to verify the SPI Flash was missing a SPI.begin() in setup().

@Takero Good idea, I will implement it ! Thanks !