iic i2c twi serial 2004 20x4 lcd module shield price

With IIC/I2C interface, it only takes two I/O port thus saving more for other usages. You can adjust the contrast by the potentiometer at its back. If you dont want the backlight, you can also unplug the jumper cap at the LCD back.

2012 latest IIC LCD2004-character LCD display module, a new high-quality 4 line 20 character LCD module not only set the contrast control knob selector switch also has a backlight and IIC communication interface. For Arduino beginners, not for the cumbersome and complex LCD driver circuit connection and a headache, the real significance of this LCD module will simplify the circuit, this module directly into the Arduino Sensor Shield V5.0 sensor expansion board IIC device interface can, GM 4P sensor connection cable, programmed through the Arduino controller, you can easily identify the slogan, sensor data records.

This IIC/I2C/TWI Serial 2004/20x4 LCD Module Shield for Arduino Uno/Mega2560 displays white contents on an elegant blue. It can display 4 rows with 20 characters for each. With IIC/I2C interface, it only takes two I/O ports thus saving more for other usages.

Easy to set up, and works with the standard "LiquidCrystal_I2C" library.Contrast adjustable as described.2 cons:1) Red glow always from the top right and bottom left corners. Not bright, but there.2) A long message line continues from line 0 to line 2, ie. it skips a line, then goes back to line 1, and then to line 3. Not sure if this is fault of the hardware, or the library driver.To note - if I place the cursor on a specific line, it prints the specified message there OK.See code below and video.#include #include // initialize the library with the numbers of the interface pinsLiquidCrystal_I2C lcd(0x27,20,4); // set the LCD address to 0x27 for a 20 chars and 4 line displaychar message[] = "This is some long message that will end up scrolling on Line0 only";int previous = 0;int pos = 0;void setup(){ lcd.init(); //initialize the lcd lcd.backlight(); //open the backlight // Print a message to the LCD. lcd.print(message); delay(5000); lcd.clear();}void printLine(int refreshSeconds){ //Check if the current second since restart is a mod of refresh seconds, //if it is then update the display , it must also not equal the previously //stored value to prevent duplicate refreshes if((millis()/500) % refreshSeconds == 0 && previous != (millis()/500)) { previous = (millis()/500);//Store the current time we entered for comparison on the next cycle lcd.setCursor(0, 0);//Set our draw position , set second param to 0 to use the top line char lcdTop[20];//Create a char array to store the text for the line int copySize = 20; // What is the size of our screen , this could probably be moved outside the loop but its more dynamic like this if(strlen(message) < 20) { //if the message is bigger than the current buffer use its length instead; copySize = strlen(message); } //Store the current position temporarily and invert its sign if its negative since we are going in reverse int tempPos = pos; if(tempPos < 0) { tempPos = -(tempPos); } //Build the lcd text by copying the required text out of our template message variable memcpy(&lcdTop[0],&message[tempPos],copySize); lcd.print(lcdTop);//Print it from position 0 //Increase the current position and check if the position + 20 (screen size) would be larger than the message length , if it is go in reverse by inverting the sign. pos += 1; if(pos +20 >= strlen(message)) { pos = -(pos); } }}void loop(){ printLine(1); // Original program line lcd.setCursor(0,1); lcd.print("This is Line1 msg"); delay(250); lcd.setCursor(0,2); lcd.print("This is Line2 msg"); delay(250); lcd.setCursor(0,3); lcd.print("This is Line3 msg"); delay(250); lcd.clear(); }

I have the screen somewhat working using the LiquidCrystal_I2C Library. It is connected to a Arduino Mega 2560 and the SDA and SCL pins are connected to the SDA and SCL on the Mega. However when I use the following code

I opened and read the LCD (ect) .H file. and found the calls that can be made. I tried inserting lcd.clear, lcd.blink, lcd.home, etc. and all seem to work.