j5 LCD Documentation

LCD.md

The LCD class constructs an object that represents an LCD Display.

Parameters

• options An object of property parameters

Property Name	Type	Value(s)	Description	Required
pins	Object	```js { rs, en, d4, d5, d6, d7 } ```	Sets the values of the rs, en, d4, d5, d6 and d7 pins.	yes

Shape

{
  board: A reference to the board object the Led is attached to
  id: A user definable id value. Defaults to null
  bitmode: Defines the bitmode of the LCD display. Options are 4bit and 8bit.
  lines: The number of lines that the LCD display supports. Defaults to 2.
  rows: The number of rows that the LCD display supports. Defaults to 2.
  cols: The number of columns that the LCD display contains. Defaults to 16.
  dots: The number of dots per column. Defaults to 5x8.
  pins : the object containing the pin values for rs, en, d4, d5, d6, d7
}

Usage

var five = require("johnny-five"), 
    board = new five.Board();

board.on("ready", function() {

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });

  lcd.on("ready", function(){
    lcd.clear();
    lcd.home();
    lcd.print("Hello");
  });
  });

API

• print(message,opts) prints the string 'message' to the LCD display at the cursor's current position
• if opts.dontProcessSpecials is set to true, it will not print out any special characters created by the useChar(charCode) function.

  // Example without dontProcessSpecials
   var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
   lcd.print('Bleep bloop');
  
  // Example with dontProcessSpecials
  lcd.useChar("heart");
  lcd.print('Hello :heart:',{ dontProcessSpecials : false });

• useChar(charCode) Creates the character in LCD memory and adds character to current LCD character map

 var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
 lcd.useChar("heart");
 lcd.print('Hello :heart:');

• clear() Clears all text on the LCD.

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.print('Bleep bloop');
  lcd.clear();

• setCursor(x,y) Sets the cursor the the position <x,y>

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.setCursor(0,0).print('Bleep'); //The starting position of the LCD display
  lcd.setCursor(0,1).print('Bloop'); //The second line, first character of the LCD display

• home() Sets the cursor the the position <0,0>

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.setCursor(0,1).print('Bloop');  //The second line, first character of the LCD display
  lcd.home().print('Bleep'); //The second line, first character of the LCD display

• display() Shows the characters on the LCD display

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.display().print('Bleep Bloop');

• noDisplay() Shows the characters on the LCD display

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.noDisplay().print('Bleep Bloop'); //You will not see this text on the LCD display

• blink() This causes the cursor to show and blink

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.blink().print('Bleep Bloop');

• noBlink() This causes the cursor to stop blinking

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.noBlink().print('Bleep Bloop');

• autoscroll() Turns on automatic scrolling of the LCD. This causes each character output to the display to push previous characters - over by one space

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.autoscroll().print('Bloop').print('Bleep');

• noAutoscroll() Turns off automatic scrolling of the LCD.

  var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] });
  lcd.noAutoscroll().print('Bloop').print('Bleep');

Events

• ready The "ready" event is emitted whenever the value of the LCD has completed setup and is ready for use.

This looks great!

I few bits of feedback and nitpicks ;)

• Double quotes please <3
• For the example code in the method descriptions, you can omit the var lcd = new five.LCD({ pins: [ 2,3,4,5,11,12 ] }); in each of them.
• The "ready" event has gone away, the LCD blocks for an imperceptible amount of time while it's initializing (but never again after that)
• Let's write useChar(charCode) as useChar(name) (I don't want it to be confused for actual char codes, ie. String.fromCharCode(...)
• Currently, pins option can only be an array, but I will fix that to match other classes that allow both an array or object.