Old lcd screen is not working (black boxes on the right half)

Good morning makers, I'm trying to use some old LCD screens, I'm using Arduino nano to control the display with the classical 4-bit configuration and the hello world sketch of the liquidCrystal library(I used also the one of newliquidCrystal library) but I can see only some black boxes on the right part of the screen.
I checked all the wires,
I checked the 10k potentiometer and it does its job
I tried to use different displays(that use similar controllers) but I have the same problem also with these.
I tried to change the board.
So I thought that the problem was the controller of the display, so I searched a little bit on the internet but I discovered that the controllers that these displays use are very similar to the common one (the HD44780), so they should work...
Does someone know how to solve this problem?

For starters your 16x1 display is actually configured as an 8x2. The first 'row' consists of the left 8 characters and the second 'row' consists of the right 8 characters.

You also have some sort of wiring/programming problem since only one of the two 'rows' has the black boxes.


You can use the hd44780 library.
Configure it for 8x2 and turn on linwrapping.
Once you do that, you can use it as if it were a 16x1 display.

The stock LiquidCrystal library does not support this capability.

--- bill

Thank you very much :slight_smile: