lcd is used as a way to display words and numbers. it's pretty neat, actually. in order to use the lcd though, you need to download this library from the internet called LiquidCrystal_I2C. you can download it here.
this is how you normally want to wire up an lcd. it looks very messy, does it not?
luckily, we can wire the lcd like this, with the help of a device called an I2C, stationed at the lcd's back. The wiring are as follows: SDA to A4, SCL to A5, vcc to live wire and gnd to ground. SDA must be at A4 or SDA pin, whereas SCL must be at A5 or the SCL pin
the SDA pin is next to the AREAF pin, whereas SCL pin is next to the SDA pin
you need to include the library that was linked eariler (or if you already have a different one downloaded, dont bother with this line.)
to include it, open your arduino program, click "sketch", followed by "include library" and then "add .ZIP Library...". go to where you saved that file, and open it from there. you can delete the downloaded copy after you have done this.
"lcd.init()" initializes your lcd. "lcd.backlight()" calls your backlight to turn on. there's also "lcd.clear" to clear screen, "lcd.setCursor(x,y)" where x is horizontal and y is vertical on a coordinates system. (0,0) means top left corner of the lcd screen. max limit depends on the size of your lcd, i.e. 1602A means (15,1) maximum (bottom rigt corner). "lcd.print()" allows you to display what you want them to display. to display a string of text, you need to write ' lcd.print("...")' in your program, where '...' is the text you want to display.
this code will count the number of seconds elapsed since the program started in seconds.
if you are unable to see the text on your lcd display, chances are you need to adjust the screw on the blue box on the I2C (the black extrusion behind the lcd). it adjusts the sensitivity of the lcd.
Here's the original code (with download link at image below!)
