rp-hal-boards/boards/pico/examples/pico_blinky.rs

102 lines
2.7 KiB
Rust
Raw Normal View History

2021-09-21 19:47:43 +10:00
//! # Pico Blinky Example
//!
2021-09-21 19:03:47 +10:00
//! Blinks the LED on a Pico board.
//!
//! This will blink an LED attached to GP25, which is the pin the Pico uses for
//! the on-board LED.
//!
//! See the `Cargo.toml` file for Copyright and licence details.
#![no_std]
#![no_main]
2021-09-21 19:03:47 +10:00
// The macro for our start-up function
use cortex_m_rt::entry;
2021-09-21 19:03:47 +10:00
// GPIO traits
use embedded_hal::digital::v2::OutputPin;
2021-09-21 19:03:47 +10:00
// Time handling traits
use embedded_time::rate::*;
2021-09-21 19:03:47 +10:00
// Ensure we halt the program on panic (if we don't mention this crate it won't
// be linked)
use panic_halt as _;
2021-09-21 19:03:47 +10:00
// Pull in any important traits
use pico::hal::prelude::*;
// A shorter alias for the Peripheral Access Crate, which provides low-level
// register access
use pico::hal::pac;
// A shorter alias for the Hardware Abstraction Layer, which provides
// higher-level drivers.
use pico::hal;
//// The linker will place this boot block at the start of our program image. We
//// need this to help the ROM bootloader get our code up and running.
#[link_section = ".boot2"]
#[used]
pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER;
2021-09-21 19:03:47 +10:00
/// Entry point to our bare-metal application.
///
/// The `#[entry]` macro ensures the Cortex-M start-up code calls this function
/// as soon as all global variables are initialised.
///
/// The function configures the RP2040 peripherals, then blinks the LED in an
/// infinite loop.
#[entry]
fn main() -> ! {
2021-09-21 19:03:47 +10:00
// Grab our singleton objects
let mut pac = pac::Peripherals::take().unwrap();
let core = pac::CorePeripherals::take().unwrap();
2021-09-21 19:03:47 +10:00
// Set up the watchdog driver - needed by the clock setup code
let mut watchdog = hal::watchdog::Watchdog::new(pac.WATCHDOG);
2021-09-21 19:03:47 +10:00
// Configure the clocks
//
// The default is to generate a 125 MHz system clock
2021-09-21 19:03:47 +10:00
let clocks = hal::clocks::init_clocks_and_plls(
pico::XOSC_CRYSTAL_FREQ,
pac.XOSC,
pac.CLOCKS,
pac.PLL_SYS,
pac.PLL_USB,
&mut pac.RESETS,
&mut watchdog,
)
.ok()
.unwrap();
2021-09-21 19:03:47 +10:00
// The delay object lets us wait for specified amounts of time (in
// milliseconds)
2021-07-27 05:16:09 +10:00
let mut delay = cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().integer());
2021-09-21 19:03:47 +10:00
// The single-cycle I/O block controls our GPIO pins
let sio = hal::sio::Sio::new(pac.SIO);
// Set the pins up according to their function on this particular board
let pins = pico::Pins::new(
pac.IO_BANK0,
pac.PADS_BANK0,
sio.gpio_bank0,
&mut pac.RESETS,
);
2021-09-21 19:03:47 +10:00
// Set the LED to be an output
let mut led_pin = pins.led.into_push_pull_output();
2021-09-21 19:03:47 +10:00
// Blink the LED at 1 Hz
loop {
led_pin.set_high().unwrap();
delay.delay_ms(500);
led_pin.set_low().unwrap();
delay.delay_ms(500);
}
}
2021-09-21 19:03:47 +10:00
// End of file