i downloaded the "new liquid crystal 1.3.4" library from here:
NEW LIQUID CRYSTAL 1.3.4 LIBRARY
using the following sample code frome here:
SAMPLE CODE
/* YourDuino.com Example Software Sketch
20 character 4 line I2C Display
Backpack Interface labelled "YwRobot Arduino LCM1602 IIC V1"
Connect Vcc and Ground, SDA to A4, SCL to A5 on Arduino
terry@yourduino.com */
/*-----( Import needed libraries )-----*/
#include <Wire.h> // Comes with Arduino IDE
// Get the LCD I2C Library here:
// https://bitbucket.org/fmalpartida/new-liquidcrystal/downloads
// Move any other LCD libraries to another folder or delete them
// See Library "Docs" folder for possible commands etc.
#include <LiquidCrystal_I2C.h>
/*-----( Declare Constants )-----*/
/*-----( Declare objects )-----*/
// set the LCD address to 0x27 for a 20 chars 4 line display
// Set the pins on the I2C chip used for LCD connections:
// addr, en,rw,rs,d4,d5,d6,d7,bl,blpol
LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE); // Set the LCD I2C address
/*-----( Declare Variables )-----*/
void setup() /*----( SETUP: RUNS ONCE )----*/
{
Serial.begin(9600); // Used to type in characters
lcd.begin(20,4); // initialize the lcd for 20 chars 4 lines, turn on backlight
// ------- Quick 3 blinks of backlight -------------
for(int i = 0; i< 3; i++)
{
lcd.backlight();
delay(250);
lcd.noBacklight();
delay(250);
}
lcd.backlight(); // finish with backlight on
//-------- Write characters on the display ------------------
// NOTE: Cursor Position: Lines and Characters start at 0
lcd.setCursor(3,0); //Start at character 4 on line 0
lcd.print("Hello, world!");
delay(1000);
lcd.setCursor(2,1);
lcd.print("From YourDuino");
delay(1000);
lcd.setCursor(0,2);
lcd.print("20 by 4 Line Display");
lcd.setCursor(0,3);
delay(2000);
lcd.print("http://YourDuino.com");
delay(8000);
// Wait and then tell user they can start the Serial Monitor and type in characters to
// Display. (Set Serial Monitor option to "No Line Ending")
lcd.setCursor(0,0); //Start at character 0 on line 0
lcd.print("Start Serial Monitor");
lcd.setCursor(0,1);
lcd.print("Type chars 2 display");
}/*--(end setup )---*/
void loop() /*----( LOOP: RUNS CONSTANTLY )----*/
{
{
// when characters arrive over the serial port...
if (Serial.available()) {
// wait a bit for the entire message to arrive
delay(100);
// clear the screen
lcd.clear();
// read all the available characters
while (Serial.available() > 0) {
// display each character to the LCD
lcd.write(Serial.read());
}
}
}
}/* --(end main loop )-- */
/* ( THE END ) */
and yes, it is wired as stated to do so..
the unit i have is:
so yes, gnd, 5v, a4, a5 connected properly
library is in the arduino libraries folder.. but named as: I2C_20x4_LCD and yes i can see it in arduino IDE under EXAMPLES
so why am i angry? no matter what example code i use.. the lcd lights up but NOTHING is displayed.. yes i have tried playing with the contrast.. but that has nothing to do with it..
so can someone please tell me what i'm doing wrong?
