Hello all
thank you very much for your quick replies,
Yesterday I've unglued the display from the PCB reviling the touch panel pads, with a multi-meter on continuity I've searched the corresponding pins, they were just like the ebay comment that msliva has pointed.
YP = A2, XM = A1, YM = 7, XP = 6
these are arduino uno pins.
these correspond to the resistor matrix that MasterT was talking about.
this way these panels don't possess a touch controller IC, only the bare resistive touch panel.
Regarding the libraries, I'm using STM32 microcontroller and not Arduino, I'll have to search or create my owns.
Again, thank you very much for the help.
Best regards, Mauro.
P.S. hope the next display doesn't arrive broken....