WiFi LoRa 32 V3 adding BME280

#1

Trying to figure out pins required. Cannot find 22scl or sda pin out.

So much info out there that comes close but not the same.

#2

Try this post:

#3

I am also looking for a working sketch for the collaboration between Heltec LoRa32 V3.1 and a BME280.

I have read a lot on the internet recently and tried out many examples, but I cannot get this combination to work.

However, with a Heltec Lora32 V2 I have no problems operating a BME 280. It works perfectly.

#4

A bit more information as to what isn’t working might help.

The most obvious difference between the V3 boards and earlier versions is the need to [declare and] use the second I2C bus for the sensor.

#5

The only way that should work is via the rear pins 17 and 18. These are not brought out, so you have to solder. But I don’t dare to do that.

So I thought there must be alternative pins.

Unfortunately, I don’t know much about the second I2C bus yet.

#6

When using the V3 board, you have to define and use the second I2C bus, NOT the first one.

#7

Can you give me an example for the bme280 (with the working pins)?

#8

The best I can do for you at the moment is point you to my project website where the subject is discussed. The panel immediately above this section includes the pin definitions that I use (e.g. in the present case, pins 19 and 20 for SDA and SCL respectively) and I generally use the Adafruit_BME280 library.

#9

Thank you very much for your help. I will look into it soon.

#10

Your website helped me a lot.

With this code (from user machepro) it now works for me:

TwoWire Wire2(1);

In the setup:

Wire2.begin(41,42); /* (GPIO SDA and SCL) */
status = bme.begin(0x76, &Wire2);

Thank you for your help.

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