MLX90614 on Wio Terminal temperature sensor (no I2C library included?)


I am trying to read temperature datas from a MLX90614 sensor connected to a Wio Terminal. I have managed to run the mlxtest from Adafruit MLX90614 library on an Arduino Nano 33 BLE Sense (just had to be careful to connect Vdd to Vin and not V33).

However it doesn't work on my Wio Terminal. I have noticed that there is no Wire library included in this exemple. Isn't it weird? (I also tried to include this library but it didn't fix the problem)


Does that mean you have 5V version of the sensor? Please post the complete product code!

I'm also missing a wiringi diagram of your setup! That includes the schematics of a breakout board if you use one for the MLX!

If you mean the mlxtest example, the Wire library is included within the library (as it should be).

Hello, thanks for the answer

No I think I have the 3V version.

Ok now it is working even on 3V3 I think I did a mistake on the wiring.

I don't have a wiring diagram but here is then the connection possible on Arduino Nano BLE

Vdd=Vin or 3V3

On the Wio Terminal,

Ok thank you for the information, I didn't think about checking inside it !

How do you power the Nano 33 BLE? By USB? Vin is connected to VUSB, so it has 5V which might fry the sensor linked to above.

I2C0 is on 27/28, on 3/5 is I2C1. If you want to use that one you have to specify that explicitly!

I didn't have any problem with other sensor (such as MAX30100 on pin 3/5 but I will try also on 27/28. I couldn't find how to specify it, do you know that ? Thanks in advance!
(I won't be able to try anything next week but I will try the week after)

You can provide the used Wire object in the begin method of the Adafruit_MLX90614 library.

I followed the rather complex numbering in the SAMD51 variant Seeed created for the WIO Terminal and it seems that they call I2C0 Wire1 and I2C1 Wire, so you're probably right with 3/5.

In the pinout on Seeed's wiki page pin 17 is 3V3 but in the diagram in the variant.h file of that board pin 17 is GND. You should check that using a multimeter and maybe change Vdd to pin 1 which is 3V3 in both documents.