mirror of
https://github.com/italicsjenga/rp-hal-boards.git
synced 2024-10-17 14:31:31 +11:00
139 lines
4.5 KiB
Rust
139 lines
4.5 KiB
Rust
//! # LCD Display Example
|
|
//!
|
|
//! In this example, the RP2040 is configured to drive a small two-line
|
|
//! alphanumeric LCD using the
|
|
//! [HD44780](https://crates.io/crates/hd44780-driver) driver.
|
|
//!
|
|
//! This example drives the LCD by pushing data out of six GPIO pins, writing
|
|
//! the data four bits at a time. A faster alternative can be created using
|
|
//! HD44780::new_8bit() but requiring an additional four GPIO pins.
|
|
//!
|
|
//! See the `Cargo.toml` file for Copyright and license details.
|
|
//!
|
|
//! ```text
|
|
//! /--------------------------------------\
|
|
//! ____________ | /-------------------------\ |
|
|
//! | 1 GND|-------+---\ | _|USB|_ | |
|
|
//! | 2 VDD|-------+---+----/ |1 R 40|-VBUS-o v
|
|
//! | 3 VS|-------/ | |2 P 39| ||POT||
|
|
//! | 4 RS|--\ o-----------GND-|3 38|-GND----------o
|
|
//! | 5 RW|--+--------/ /------GP2-|4 P 37|
|
|
//! | 6 EN|--+-\ /--+------GP3-|5 I 36|
|
|
//! | 7 | | | /--+--+------GP4-|6 C |
|
|
//! | 8 | | | /--+--+--+------GP5-|7 O |
|
|
//! | 9 | | \--+--+--+--+---\ |8 |
|
|
//! | 10 | \----+--+--+--+-\ \-GP6-|9 |
|
|
//! | 11 D4|-------/ | | | \---GP7-|10 |
|
|
//! | 12 D5|----------/ | | .........
|
|
//! | 13 D6|-------------/ | |20 21|
|
|
//! | 14 D7|----------------/ """""""
|
|
//! ..............
|
|
//! Symbols:
|
|
//! - (+) crossing lines, not connected
|
|
//! - (o) connected lines
|
|
//! ```
|
|
//!
|
|
//! See the `Cargo.toml` file for Copyright and license details.
|
|
|
|
#![no_std]
|
|
#![no_main]
|
|
|
|
// The macro for our start-up function
|
|
use cortex_m_rt::entry;
|
|
|
|
// Ensure we halt the program on panic (if we don't mention this crate it won't
|
|
// be linked)
|
|
use panic_halt as _;
|
|
|
|
// Pull in any important traits
|
|
use rp_pico::hal::prelude::*;
|
|
|
|
// GPIO traits
|
|
use embedded_hal::digital::v2::OutputPin;
|
|
|
|
// Time handling traits
|
|
use embedded_time::rate::*;
|
|
|
|
// For LCD display
|
|
use hd44780_driver::HD44780;
|
|
|
|
#[entry]
|
|
fn main() -> ! {
|
|
// Grab our singleton objects
|
|
let mut pac = rp_pico::hal::pac::Peripherals::take().unwrap();
|
|
let core = rp_pico::hal::pac::CorePeripherals::take().unwrap();
|
|
|
|
// Set up the watchdog driver - needed by the clock setup code
|
|
let mut watchdog = rp_pico::hal::Watchdog::new(pac.WATCHDOG);
|
|
|
|
// Configure the clocks
|
|
// The default is to generate a 125 MHz system clock
|
|
let clocks = rp_pico::hal::clocks::init_clocks_and_plls(
|
|
rp_pico::XOSC_CRYSTAL_FREQ,
|
|
pac.XOSC,
|
|
pac.CLOCKS,
|
|
pac.PLL_SYS,
|
|
pac.PLL_USB,
|
|
&mut pac.RESETS,
|
|
&mut watchdog,
|
|
)
|
|
.ok()
|
|
.unwrap();
|
|
|
|
// The single-cycle I/O block controls our GPIO pins
|
|
let sio = rp_pico::hal::Sio::new(pac.SIO);
|
|
|
|
// Set the pins up according to their function on this particular board
|
|
let pins = rp_pico::Pins::new(
|
|
pac.IO_BANK0,
|
|
pac.PADS_BANK0,
|
|
sio.gpio_bank0,
|
|
&mut pac.RESETS,
|
|
);
|
|
|
|
let mut led_pin = pins.led.into_push_pull_output();
|
|
|
|
// The delay object lets us wait for specified amounts of time
|
|
let mut delay = cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().integer());
|
|
|
|
// Init pins
|
|
let rs = pins.gpio7.into_push_pull_output();
|
|
let en = pins.gpio6.into_push_pull_output();
|
|
let d4 = pins.gpio5.into_push_pull_output();
|
|
let d5 = pins.gpio4.into_push_pull_output();
|
|
let d6 = pins.gpio3.into_push_pull_output();
|
|
let d7 = pins.gpio2.into_push_pull_output();
|
|
|
|
// LCD Init
|
|
let mut lcd = HD44780::new_4bit(rs, en, d4, d5, d6, d7, &mut delay).unwrap();
|
|
|
|
loop {
|
|
// Clear the screen
|
|
lcd.reset(&mut delay).unwrap();
|
|
lcd.clear(&mut delay).unwrap();
|
|
|
|
// Write to the top line
|
|
lcd.write_str("rp-hal on", &mut delay).unwrap();
|
|
|
|
// Move the cursor
|
|
lcd.set_cursor_pos(40, &mut delay).unwrap();
|
|
|
|
// Write more more text
|
|
lcd.write_str("HD44780! ", &mut delay).unwrap();
|
|
let mut char_count = 9;
|
|
for ch in "move along!.. ".chars() {
|
|
if char_count > 15 {
|
|
// Switch autoscroll on
|
|
lcd.set_autoscroll(true, &mut delay).unwrap();
|
|
}
|
|
led_pin.set_high().unwrap();
|
|
lcd.write_char(ch, &mut delay).unwrap();
|
|
char_count += 1;
|
|
delay.delay_us(400_000); //0.4s
|
|
led_pin.set_low().unwrap();
|
|
delay.delay_us(100_000); //0.1s
|
|
}
|
|
lcd.set_autoscroll(false, &mut delay).unwrap();
|
|
}
|
|
}
|