To link a standard 16×2 LCD directly with the microcontroller, for instance Arduino, you would need atleast 6 I/O pins to talk to the LCD. However, if you use an LCD module with I2C interface ... This ...

Necessity is the mother of invention, so he put together this I2C sniffer sketch for Arduino. The arduino will record what is going on for a set time interval, then dump the data via serial as a .csv.

Inexpensive OLED displays with I2C interfaces abound, but there is a catch: they tend to be stuck on I2C address 0x3C. Some have a jumper or solder pads to select an alternate (usually 0x3D), but ...