Why the command noDisplay() clear all LCD screen? i want to preserve video information for long time without communicating with arduino on lcd 1602, i'm tryng to use the command of liquidCrystal library noDisplay() but when i use it,this clear all display. On arduino website here is the description of this command "Turns off the LCD display, without losing the text currently shown on it." but i lose all on screen. Thanks for reply

there is my test code 

#include &lt;LiquidCrystal.h&gt;

// 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() {
  // Turn off the display:
  lcd.noDisplay();
  delay(500);
  // Turn on the display:
  lcd.display();
  delay(500);
}


with this code display blinking and don't show continuos "hello word".
I tried out your code. It's working absolutely fine.

Whenever lcd.noDisplay() executes then LCD not displaying hello, word!...
And whenever lcd.display() executes then LCD displaying hello, word!...

So, that's why "hello word" not continuously displaying.

And you can also find the display() and noDisplay() functions to turn on and off
the display comment on top of arduino sketch.