serlcd

Simple wrappers for communicating to the SerLCD 2.5

npm install serlcd
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SerLCD

Simple wrappers for communicating to the SerLCD.

Implemented using the Datasheet

This has been only tested using LCD-09395 but it should work in theory with other USB-to-UART enabled LCDs that use the same HD44780 command set.

In order to facilitate easier communication to the LCD and to ensure it receives all the write commands, calling write writes your string or buffer to a write queue that is polled on (and flushed to the serial port) once every 50 milliseconds.

Note: In my experience writing to the backlight a lot seemed to confuse the device (it writes to the EEPROM every time you make a backlight change) so it's probably not a good idea to do so in rapid succession.

Usage

var serlcd = require('serlcd');
var lcd = new serlcd("/dev/ttyUSB0");

lcd.clearScreen();
lcd.write("Hooray!");

API Reference

  • write: Write to the screen. You can use a string, or a Buffer. For example:

      lcd.write('Hooray');
      lcd.write(new Buffer([0xFE, 0x01]));
    
  • clearScreen: Clears the screen.

  • clearAndWrite: Clears the screen (resetting the cursor position to 0), then writes a string/buffer.
  • writeTopLine: Reset the cursor to the top line and write a string (not a buffer) to the top line (without removing the bottom line).
  • writeBottomLine: Reset the cursor to the bottom line and write a string (not a buffer) to the bottom line (without removing the top line).
  • backlightOff: Turn the backlight off.
  • backlight40: Set backlight to 40%
  • backlight73: Set backlight to 73%
  • backlight100: Set backlight to 100% (max brightness)

TODO/Not implemented

  • Move cursor left
  • Move cursor right
  • Scroll left
  • Scroll right
  • Turn visual display on
  • Turn visual display off
  • Underline cursor on
  • Underline cursor off
  • Blinking box cursor on
  • Blinking box cursor off
  • Set arbitrary cursor position
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