I have a problem with the PCF8575 module, if I compile indicating that I am using it, the screen remains blank while if I indicate that I am not using it correctly. I enclose the scheme of the circuit that I am using and that I believe is correct. Could it be that the module is defective ?.
It is as if it were not connected and I have verified that pins 20 and 21 have continuity and that the 5 Vs arrive correctly.
Am I doing something the wrong way?
As soon as a new PCF8575 arrives I will change it, but on the other hand I find it strange that it fails