@jmarcelino It's without ADC (maybe I need to do it with an ADC). It's just a pin defined as input like :pin = Pin('P19', mode = Pin.IN, pull = Pin.PULL_DOWN) pin.value()
which gives me a simple 0 or 1 (I guess 1 when the voltage is at least half of the 3v3?).
I will check what the ADC version gives me next week (I have no module with me unfortunately this week-end). It might give me the reading I want.
Also thanks Robert for your answer, I will have a look into the pin sheets of the module.