Crate ag_lcd

source ·
Expand description

AG-LCD

This is a rust port of the LiquidCrystal library. LiquidCrystal is a standard C++ library that allows developers to control a HITACHI HD44780 LCD screen with one or two 16-character lines. Alternatives to this library (that I’ve investigated) are:

I decided to create a more comprehensive solution because existing libraries were either incomplete or somewhat complicated to use. This library uses traits from embedded-hal and should work with any hardware abstraction layer that uses the same types. Currently this crate has only been tested with avr-hal and all example code and comments assume you’re using avr-hal as well.

Most features (blink, cursor, text direction etc.) can be set either through a general set_ function that accepts one or two arguments (like set_blink), through specific conveniance functions (blink_on rather than set_blink) or with a builder function (like with_blink).

If some functions are missing for a settings, its either because it doesn’t make sense for that particular setting, or because that feature can only be set before the build method is called (in which case only a with_ function is provided).

Usage

use ag_lcd::{Display, Blink, Cursor, LcdDisplay};

let peripherals = arduino_hal::Peripherals::take().unwrap();
let pins = arduino_hal::pins!(peripherals);
let delay = arduino_hal::Delay::new();

let rs = pins.d12.into_output().downgrade();
let rw = pins.d11.into_output().downgrade();
let en = pins.d10.into_output().downgrade();
// let d0 = pins.d9.into_output().downgrade();
// let d1 = pins.d8.into_output().downgrade();
// let d2 = pins.d7.into_output().downgrade();
// let d3 = pins.d6.into_output().downgrade();
let d4 = pins.d5.into_output().downgrade();
let d5 = pins.d4.into_output().downgrade();
let d6 = pins.d3.into_output().downgrade();
let d7 = pins.d2.into_output().downgrade();

let mut lcd: LcdDisplay<_,_> = LcdDisplay::new(rs, en, delay)
    // .with_full_bus(d0, d1, d2, d3, d4, d5, d6, d7)
    .with_half_bus(d4, d5, d6, d7)
    .with_display(Display::On)
    .with_blink(Blink::On)
    .with_cursor(Cursor::On)
    .with_rw(d10) // optional (set to GND if not provided)
    .build();

lcd.set_cursor(Cursor::Off);
lcd.set_blink(Blink::Off);

lcd.print("Test message!");

Structs

Enums

  • AutoScroll
    Flag that sets the display to autoscroll
  • Backlight
    Flag that sets backlight state
  • Blink
    Flag that sets cursor background to blink
  • Cursor
    Flag that sets the cursor on/off
  • Display
    Flag that sets the display on/off
  • Error
    Error type for LcdDisplay, returned by LcdDisplay::error
  • Layout
    Flag that controls text direction
  • Lines
    Flag for the number of lines in the display
  • Mode
    Flag for the bus mode of the display
  • Scroll
    Flag used to indicate direction for display scrolling
  • Size
    Flag for the character size of the display