LCD contrast not working

please help me this is how it's wired

It works immeasurably better if you connect power to the LCD display. Pins 1 and 2.

If your LCD has a resistor of 100 ohms - "101" - for R8 and R9 is zero (or vice versa) - as I am quite sure it does - then you do not need the 220 ohm resistor, just connect pins 15 and 16 directly (to Vcc and ground). What is also puzzling is that your photograph does not show the backlight alight either - does it light or not?

yes it lights up but how do i control contrast
i setted it up correctly?

this is what i followed

this is the BOOK

and this is proof that the LCD works

i did it like this

my board is wired the same

From reply # 2:

... and this is proof that the LCD works

This is proof that the LED backlight works. The LED backlight (pins 15 and 16) is totally independent of the LCD (pins 1 -14) itself.

As far as the LCD is concerned you have connected only one wire whereas you need three to get it functioning and another six to get it to display anything.

From reply #3:

my board is wired the same

That's hard for us to verify. It looks like both of the yellow power wires may be connected to + on the breadboard end. Did you notice that Adafruit used shorter wires with differing colors so that they could be easily followed?

Did you adjust the potentiometer?


i dont have that short wires in my starter kit

it's all connected the same as in the tutorial

i dont have that short wires in my starter kit

But you do have wires of two different colors. Why don't you consistently use one color for + and the other for - instead of one color for the backlight power and the other for the LCD power?

What do you see when you remove the potentiometer and connect LCD pin 3 to GND?

I suggest that you put the term LCD boxes into the search box at the upper right and then find my generic step-by-step procedure to get your LCD functioning.