Blank 1602 LCD in 'Hello World'

Using Arduino Displays
1

Hello there,

I am quite new to Arduino, but I really need some help. I started with a few tutorials and got the starter kit. Now, I am working on the default 'Hello World' on an LC Display, but the Screen is just empty. I looked over my wires several times, but I cannot find any mistakes.

What am I doing wrong? Please help quickly :frowning:

#include <LiquidCrystal.h>

const int rs = 7, en = 8, d4 = 9, d5 = 10, d6 = 11, d7 = 12;
LiquidCrystal lcd(d7, d6, d5, d4, en, rs);

void setup() {
lcd.begin(16, 2);
// Print a message to the LCD.
lcd.print("hello, world!");
}

void loop() {
lcd.setCursor(0, 1);
lcd.print(millis() / 1000);
}

Here is a picture of my setting:

index.jpg
index.jpg1600×900 193 KB

2

Thanks for the good photo.

Look at the blue line on the breadboard. There is a gap between row 30 and 32.
Join each half of the broken blue line with a jumper.
Join each half of the broken red line with a jumper.

Or just move the red and black jumper wires for the pot to row 32 on the blue and red bus lines.

David.

3

Hi David,

Thanks a lot for your quick answer. I totally understood it, but neither of your suggestions solved my problem, even though it was one big mistake I made.

Is it possible that there is some problem with my potentiometer or the connection to it?

4

Forget about the potentiometer.
Just connect pin #3 (VO) to GND. e.g. pin#1

If that does not work, test every jumper wire by replacing pin#16 jumper wire.

David.

Oops. Your constructor was:

LiquidCrystal lcd(d7, d6, d5, d4, en, rs);

It should be as shown in Libaries documentation:

LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
5

Yes, that helped... One jumper was just broken!