特別注意：如果LCD沒顯示可能是對比的問題，背板有一個藍色可變電阻調整
I2C的ADDRESS可以用i2c_scanner找出來
https://bitbucket.org/fmalpartida/new-liquidcrystal/downloads
http://jaredstemen.blogspot.tw/2014/01/getting-funduino-1602-lcd-to-print.html
// Comment
GND => GND
VCC => 5V
SDA => A4
SCL => A5
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
// 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
//none
void setup(){
// Used to type in characters
Serial.begin(9600);
// initialize the lcd for 20 chars 4 lines and turn on backlight
lcd.begin(16,2);
// ------- 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: CHAR, LINE) 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");
lcd.setCursor(0,0);
}
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());
}
}
}