hd44780-driver
Implementation of the embedded-hal traits for the HD44780.
Examples
Examples for several different boards can be found here
Any platform that implements the embedded-hal traits is supported by this library! See awesome-embedded-rust for a list of supported platforms.
Getting Started
This library aims to keep it simple in that to get started all you will have to do is supply the HD44780::new function a bunch of pins from your platform that implement the OutputPin trait for embedded-hal as well as a struct that implements the delay traits DelayUs and DelayMs.
// It is recommended to use push/pull output pins, but if your specific LCD device has pull-up resistors
// an open/drain output pin should work too
let mut delay = Delay::new();
let mut lcd = HD44780::new(
DisplayOptions8Bit::new(MemoryMap1602::new())
.with_pins(FourBitBusPins {
rs: d4.into_push_pull_output(&mut port), // Register Select pin,
en: d3.into_push_pull_output(&mut port), // Enable pin,
d4: d9.into_push_pull_output(&mut port), // d4,
d5: d10.into_push_pull_output(&mut port), // d5,
d6: d11.into_push_pull_output(&mut port), // d6,
d7: d12.into_push_pull_output(&mut port), // d7,
}),
&mut delay,
)
.unwrap();
// Unshift display and set cursor to 0
lcd.reset(&mut delay);
// Clear existing characters
lcd.clear(&mut delay);
// Display the following string
lcd.write_str("Hello, world!", &mut delay);
// Move the cursor to the second line
lcd.set_cursor_xy((0, 1), &mut delay);
// Display the following string on the second line
lcd.write_str("I'm on line 2!", &mut delay);
Async API
The async API is similar to the sync API. The the major differences are that:
- The async API requires the
asyncfeature to use. - The async API requires the nightly compiler because of use of unstable features.
- The async API uses
embedded-hal-asyncrather thanembedded-haltraits.
Embassy provides some implementations of these traits for some MCUs, and provides
an executor that can execute futures. However, projects implementing embedded-hal-async traits,
including this project, can run on any executor with any driver, provided such
executor and driver also implement embedded-async-traits.
use hd44780_driver::setup::DisplayOptions8Bit;
use hd44780_driver::memory_map::MemoryMap1602;
use hd44780_driver::bus::FourBitBusPins;
let mut delay = embassy::time::Delay::new();
pin_mut!(delay);
let mut display = HD44780::new(
DisplayOptions8Bit::new(MemoryMap1602::new())
.with_pins(FourBitBusPins {
rs,
en,
d4,
d5,
d6,
d7,
}),
delay.as_mut(),
)
.await
.unwrap();
display.clear(delay.as_mut()).await;
display.write_str(msg, delay.as_mut()).await;
Features
- 4-bit & 8-bit modes are supported
- Support for i2c backpacks
- Non-blocking API
Todo
- Busy flag support
- A more user-friendly API with additional features
- Custom characters
Contributing
-
Additional issues as well as pull-requests are welcome.
-
If you have a platform not yet covered in this repository that is supported by embedded-hal, a pull-request of an example would be awesome!
License
This project is licensed under MIT license (LICENSE or https://opensource.org/licenses/MIT)