Hi Klaus,
I am aware of this fact with Nano33BLE.
a) I used the 3.3V
b) I used external 5V power supply
In both cases the same problem still existed. I think it is related to some "configuration" issues about SDA/SCL pins because there is no "i2c" communication going on at all (tested with oscilloscope). As a cross test I did the same test with LTR390 - and voila I got signals ...
hence there seems something broken in the code ... but hard to find where this might be.
Does embody has an idea?