Problem with LCD-Display (strange rectangles in display)

Using Arduino Displays
1

Hello everybody, :smiley:

3264×2448 331 KB

As you can see in the picture I have build a display with an RTC-Modul and a LCD-Display with HD44780 driver support. Nevertheless I always get those strange rectangles. Four rectangles in the end of each line. I've already checked, the wire connections with the Arduino, and I tried to display other strings, e.g. with the Hello World sketch in the examples of the IDE.

What is the error? Has the display some faults? Because the rectangles are always there. So I cant use those eight chars :frowning:

Sorry for my bad English. But I think the English Forum has more people who are able to help me.

Yours,

nitzjoh

2

Try posting your picture again. There are some restrictions on what you can do in your first post.

Also post the code that produced the picture.

... and I tried to display other strings, e.g. with the Hello World sketch in the examples of the IDE.

Did you get the rectangles?

Don

3

Four rectangles of solid colour (same as the characters)?

Characteristic of a faulty display connection in the "Zebra" strip, may sometimes be corrected by fiddling with the lugs projecting through the PCB that hold the bezel in place or failing that, carefully disassembling and reassembling the display.

Given that there is no other fix for it and you cannot (economically) return the display under warranty, it can be worth the risk to fiddle with it.

If on the other hand it is actually a faulty connection between the "master" and "slave" COB chips on the PCB, it's toast.

4

Thank you for your help guys, but I must disappoint you, because the problem is'nt there anymore. :slight_smile: I do not know why it is away. As I turned on my Arduino today, the strange rectangles are away, and now I am able to use the places, where the rectangles were yesterday.

I think, that one connectionwire doesnt worked well. :confused:

Nevertheless thank you for your help! :grin:

EDIT Doh! After 10 minutes, the same fault comes again! I started the "Hello World" sketch from the examples, and there are the same strange rectangles!

My Arduino: Original Arduino UNO R3
Uploaded sketch:

/*
  LiquidCrystal Library - Hello World

 Demonstrates the use a 16x2 LCD display.  The LiquidCrystal
 library works with all LCD displays that are compatible with the
 Hitachi HD44780 driver. There are many of them out there, and you
 can usually tell them by the 16-pin interface.

 This sketch prints "Hello World!" to the LCD
 and shows the time.

  The circuit:
 * LCD RS pin to digital pin 12
 * LCD Enable pin to digital pin 11
 * LCD D4 pin to digital pin 5
 * LCD D5 pin to digital pin 4
 * LCD D6 pin to digital pin 3
 * LCD D7 pin to digital pin 2
 * LCD R/W pin to ground
 * 10K resistor:
 * ends to +5V and ground
 * wiper to LCD VO pin (pin 3)

 Library originally added 18 Apr 2008
 by David A. Mellis
 library modified 5 Jul 2009
 by Limor Fried (http://www.ladyada.net)
 example added 9 Jul 2009
 by Tom Igoe
 modified 22 Nov 2010
 by Tom Igoe

 This example code is in the public domain.

 http://www.arduino.cc/en/Tutorial/LiquidCrystal
 */

// include the library code:
#include <LiquidCrystal.h>

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {
  // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.print("hello, world!");
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(0, 1);
  // print the number of seconds since reset:
  lcd.print(millis() / 1000);
}


Sorry. The picture is very large. :smiley: I'll change it next time :wink:

5

Thank you for your help guys, but I must disappoint you, because the problem is'nt there anymore.
. . .
EDIT Doh! After 10 minutes, the same fault comes again!

Then it is almost definitely a problem with the 'Zebra strip' as mentioned above.

Also - You really should test your links after posting them.

Don

6

well :relaxed:, thank you for your help, Don.

I'll keep it in mind

7

floresta:
Also - You really should test your links after posting them.

Yes, whether or not that picture is very large, it is inaccessible.

8

Thats stránge. Usually I upload my pics alway to image to bayimg. :~ I dont know, why they are not available.

I uploaded the picture on an other hoster:

I am so sorry. I am a noob.

9

nitzjoh:
Thats stránge. Usually I upload my pics alway to image to bayimg. I dont know, why they are not available.

Because you have presumably uploaded them as "private".

The "free" image hosting services nowadays are useless. I can't see the large version of that current image (presumably) because my security settings do not permit all its crap to load. It is much more reliable to upload it to the forum server using "Additional Options..." below the submission window.

You are using an "international" keyboard, by the way. :smiley:

The picture illustrates the fault I (and others) described.

10

Paul__B:
Because you have presumably uploaded them as "private".

The "free" image hosting services nowadays are useless. I can't see the large version of that current image (presumably) because my security settings do not permit all its crap to load. It is much more reliable to upload it to the forum server using "Additional Options..." below the submission window.

Interessting off-topic information! Thank you for your hints!

Paul__B:
You are using an "international" keyboard, by the way. :smiley:

What do you want to tell me? :smiley:

11

nitzjoh:

Paul__B:
You are using an "international" keyboard, by the way. :smiley:

What do you want to tell me? :smiley:

Accidentally typed some international characters. :astonished: