char-lcd

Character LCD display emulator

Emulate Hitachi HD44780 and compatible devices in HTML

HD44780-A00 (Japanese standard font)

HD44780-A02 (European standard font)

Install

npm install char-lcd --save
or yarn add char-lcd
or clone the whole project from GitHub

Usage

Web Component (Polymer)

https://github.com/jazz-soft/polymer-char-lcd

Plain HTML

<script src="char-lcd.js"></script>
//...

CDN (jsdelivr)

<script src="https://cdn.jsdelivr.net/npm/char-lcd"></script>
//...

CDN (unpkg)

<script src="https://unpkg.com/char-lcd"></script>
//...

CommonJS

var CharLCD = require('char-lcd');
//...

TypeScript / ES6

import { CharLCD } from 'char-lcd';
//...

AMD

require(['char-lcd'], function(CharLCD) {
  // ...
});

Example

<div id="lcd"></div>

<script>
  var lcd = new CharLCD({ at: 'lcd', rows: 4, cols: 16, rom: 'eu' });

  // Example 1: Display a single custom character at row 0, column 0
  // To set a custom character, use String.fromCharCode to map a character byte (16-255).
  // In this case, use character code 16, which is the first non-blank character in the set.
  lcd.char(0, 0, String.fromCharCode(16));  // Set the custom character at row 0, column 0

  // Example 2: Display another custom character at row 1, column 0
  lcd.char(1, 0, String.fromCharCode(17));  // Set another custom character at row 1, column 0

  // Example 3: Display a string with mapped Unicode characters
  // The lcd.text() function will automatically map Unicode characters to the internal character set.
  lcd.text(2, 1, "Hello LCD!");
  lcd.text(3, 0, "ЁЛКИ-ПАЛКИ!");
</script>

API

constructor

var lcd = new CharLCD(params);
params is an object with the following keys:

• at: a DOM element in which to place the object, or its id; default: at the bottom of the page;
• rom: jp (default) for Japanese standard font, or eu for European standard font.
• rows: number of rows; default: 2;
• cols: number of columns; default: 16;
• pix: pixel size; default: 3;
• brk: space between pixel; default: 1;
• off: character pixel off color (background); default: #cd2;
• on: character pixel on color; default: #143;
• transitionDuration: character pixel transition duration; default: 100ms;

Unlike the real hardware where only certain combinations of rows/cols exist, there are no restrictions in the simulator;

char(r, c, h)

lcd.char(r, c, h); - set the character at row r, column c to byte h.

text(r, c, s)

lcd.text(r, c, s); - print string s at row r, column c.
This function treats \n as new line and maps UNICODE characters to the internal character set.

font(n, data)

lcd.font(n, data); - define the pixels for the n-th character; data is an array of up to 10 bytes.
In real hardware, only first 8 characters can be changed, but there is no such limitation in the simulator.

clear()

lcd.clear(); - clear all characters in LCD.