Arduino LCD 2x16 BL Shield displaying only boxes on top row.

[sooishanghei]

I wasted my #^%#@ money on U&)@*$)(@ Arduino LCD 2x16 BL Shield.

Ok. Now it displays only boxes on the FU I mean top row.

Why this happens? I tried all codes from internet and no one work. Everytime boxes on top row.

I tried adjusting potentiometer. Now I can see boxes sharper . Cool.

Here is my (current) code:

#include <Wire.h>
#include <LiquidCrystal.h>
 
// select the pins used on the LCD panel
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
void setup()
{
  pinMode(10, INPUT);
  pinMode(9, INPUT);
 lcd.begin(16, 2);
 lcd.setCursor(0,0);
 lcd.print("sweet jesus");
}
  
void loop()
{
}

Also It can work with only bottom shield connected lol

[Paul_B]

OK, let's see the "U&)@*$)(@" photos.

Taken in full daylight but not direct sun, not in a dark room, with a decent camera and perfect focus.

[sooishanghei]

[floresta]

noiasca:
your code doesn't print on second row ... so what do you expect?

I expect to see one of these:

• A row of text
• A blank screen if the contrast is set too far in one direction
• Two rows of boxes if the contrast is set too far in the other direction
  Don

[floresta]

This is going to mess things up a bit in terms of the Enable signal.

  pinMode(9, INPUT);

Don

[Paul_B]

floresta:
This is going to mess things up a bit in terms of the Enable signal.

  pinMode(9, INPUT);

Frankly, I can't see why it would cause a problem in that context.

[sooishanghei]

I changed code

#include <Wire.h>
#include <LiquidCrystal.h>
 
// select the pins used on the LCD panel
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
void setup()
{
  pinMode(10, INPUT);
 lcd.begin(16, 2);
}
  
void loop()
{
 lcd.setCursor(0,0);
 lcd.print("first line");
 lcd.setCursor(0,1);
 lcd.print("second line");
 delay(1000);
 lcd.clear();
}

It still is the same. It seems like it's not affected by changing code. I tried also change lcd.begin(); but nothing

I expect to see one of these:

A row of text
A blank screen if the contrast is set too far in one direction
Two rows of boxes if the contrast is set too far in the other direction

I have very dim boxes on bottom (where text should be also) and all (16) white boxes on top row.

[bperrybap]

It could be the pin mapping. While the pin mapping you have selected is by far the most popular it isn't the only mapping used on LCD keypad shields like that.
Get out your ohm meter and check the pin mapping. It will only take a few minutes ( it is only 6 pins)
You will either confirm that what you have is correct, or will find out what the mapping really is.
Or find out if there is a broken connection to any of the LCD pins.
Verifying the pin mapping and checking the connections for opens & shorts should be a first step with an issue like this.

--- bill

[Paul_B]

Oh for goodness sake!

You guys have forced me to get out the board and run the IDE for the first time - since before Covid!

Plugged it in, first got the display as in #3.

Loaded the code from the OP, made one modification to line 12, and ran upload. What happened?