LCD 1602A doesn't initialize correctly

Greetings,

I was dealing with my Arduino / LCD Display project for a wile and being consulting several related topics without luck yet.

The problem that i'm having is that i wasn't able to make the display initialize properly in terms of backlights and character places (dotted boxes 16x2) that should appear on the display once the energy sources are properly connected.

i'm not talking about a contrast problem, since i wasn't able to reach that point of the project yet, it seems to be something related to current or voltage, but i wasnt able to identify the problem.

i'm attaching images of the protoboard, the lcd and a video (LCD 1602A behavior video - YouTube) illustrating the behavior.

Hope someone can help me to find the problem.

Thanks!

Harkoy

Follow world conventions.
e.g. Red wires for +5V. Red bus line on breadboard for +5V
e.g. Black wires for 0V (GND). Blue bus line on breadboard for 0V (GND)

Of course you might run out of the correct coloured wires.
Choose Red, Orange, ... for +ve. Black, Blue, ... for -ve.

Or use plain solid core wire that you cut to length. And lay the wires neatly on the breadboard. So you can see exactly which holes they plug into.

This will take 10 minutes from your life. But it will improve your hair retention.

David.

". . . i'm not talking about a contrast problem . . . "

Yes you are.

You must also deal with LCD pin 3 before you will see anything. For starters just connect pin 3 to GND.

Don

LCD 1602A blue back.jpg

LCD 1602A blue front.jpg

LCD 1602A protoboard.jpg

OK , you need to connect the contrast voltage - pin 3 - before you expect to see anything on the display. Connect the wiper of a potentiometer - 10k or even better, a 1k - to pin 3 and one end to ground. Do not connect the potentiometer to Vcc. Adjust it until you see a row of blocks on the first row (only), then proceed and connect the other pins.

To head off a potential problem in the future ...

... be aware that the breaks (near the number 30) in the blue and red lines on your breadboard correspond to breaks in the corresponding horizontal bus bars.

Some breadboards have these breaks, others don't.

Don