@alexsh1 Very true :) Anyways, thanks for the tips!

@alexsh1 I just realized my full blown stupidity. The breadboard I am using has the buses connected half way and I was convinced they were fully connected. So the light sensor was not getting power, obviously. :man-facepalming: :man-facepalming: :man-facepalming: :man-facepalming: :sweat_smile: :sweat_smile: :sweat_smile: :sweat_smile:

It works now.

@alexsh1 Thanks I will check it out and give it a try! :) I'll let you know the results

@alexsh1 I think I will try to get a more reliable FTDI since this one seems to give me some troubles. It also isn't properly detected on my PC sometimes. Is there a reliable one I could get from, for example, aliexpress, you recommend? My knowledge on these is close to zero, hahaha. Thanks. :)

@alexsh1 Hm that seems reasonable. The FTDI board I have seems to be a bit funky it gives a lot of errors when I am trying to upload sometimes. Could that be related? I am not sure if it is the FTDI or the mini pro itself though.

I don't have another type with me though.

@alexsh1 I ran this example: https://playground.arduino.cc/Main/I2cScanner (I'm not sure if this is what you meant).

It seems to hang on Wire.endTransmition() it prints the string "Scanning..." but nothing else.

@alexsh1 There doesn't seem to be no RF issues, no. The freezing occurs on Wire.endTransmition(), not begin. I meant the begin function of the BH1750 library from MySensors, sorry if that wasn't very clear.

SDA and SDL seem to be connected correcly. I've checked that a few times now.

Not at the moment but I ordered a DHT22 sensor I can try that when it arrives.

I have tried with both a GY-302 and a GY-30 and both don't work although they show different problems (mentioned on my OP). Both the sensors work well when connected to the pi.

I don't have a drawing of the circuit but I can show you a picture, if it helps.

The diagram is essential like this one but without the temperature sensor and I am currently using an FTDI board to provide the power, instead of a battery.

The SCL is connected to A5 and the SDA to A4 of the mini pro.

I can also do a drawing, if further info is required but, as I said, it is like the one I linked above.

@alexsh1 said in BH1750 library hangs:

ESP8266

You mean a different model? Unfortunately I don't have another model to test it, only mini pro. I have tried another mini pro (same manufacturer though). I also don't have another model of the radio. But the messages are being sent properly so I am not sure if the problem could come from that.

Hello everyone!

I have been am trying to make a wireless light sensor to connect to my home assistant. As of now I have been successfully using one connected directly to the pi but I want to be able to eventually use different ones and spread them around the house so I decided to go with MySensors for that.

I have an Arduino mini pro connected to an NRF24L01+ wireless radio that uses my Pi as the gateway. I have successfully established a connection and I am able to send messages to the Pi and see the results in home assistant.
What I don't seem to be able to do is get information from the light sensor. I am using a BH1750 light sensor for that.

I have two versions, one is the GY-302 (small one) and the other GY-30 (longer one). They both work well when connected directly to the pi. I can get light levels both through a python script and directly to home assistant.
When I connect them to my arduino though the BH1750 library doesn't work.

• With the GY-302 it just crashes on calling begin. I have dug under the library and realized it hangs on the call endTransmission.
• With the GY-30 it does not hang but instead it always reports the same value of lux, no matter how much light I put on it or how much light I remove from it. The value is always 54612.

I am a software engineer by profession so my circuit skills are extremely low and it is likely I am doing something wrong.
At first I thought that, since I am a newbie, I fried something while soldering so I soldered a new mini pro (same manufacturer) but I got the same results.

I was mostly following this guide online: http://sebastiaanschimmel.me/blog/2015/06/arduino-temp-hum-light-sensor.html so my circuit looks like the one described (without the temperature sensor). I can send pictures of it if required.

The boards I got are the following:
https://www.aliexpress.com/item/WAVGAT-Atmega328-3-3V-Version-Pro-Mini-Module-16M-For-Arduino-Compatible/32820596876.html?spm=a2g0s.9042311.0.0.rYlqk6
https://www.aliexpress.com/item/1Pcs-New-Arrival-BH1750FVI-GY-302-GY302-Digital-Light-intensity-Sensor-BH1750-16bitAD-Module-For-AVR/32821717980.html?spm=a2g0s.9042311.0.0.rYlqk6
https://www.aliexpress.com/item/1pc-Basic-Breakout-Board-For-FTDI-FT232RL-USB-to-Serial-IC-For-Hot-Top-Sale/32648158894.html?spm=a2g0s.9042311.0.0.2Wt045

Hope someone is able to help! :)

Thanks and sorry for the long post!!