mirror of
https://github.com/italicsjenga/rp-hal-boards.git
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82 lines
2.3 KiB
Rust
82 lines
2.3 KiB
Rust
//! # Pico GPIO In/Out Example
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//!
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//! Toggles the LED based on GPIO input.
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//!
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//! This will control an LED on GP25 based on a button hooked up to GP15. The
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//! button should cause the line to be grounded, as the input pin is pulled high
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//! internally by this example. When the button is pressed, the LED will turn
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//! off.
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//!
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//! See the `Cargo.toml` file for Copyright and licence details.
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#![no_std]
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#![no_main]
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// The macro for our start-up function
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use cortex_m_rt::entry;
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// GPIO traits
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use embedded_hal::digital::v2::{InputPin, OutputPin};
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// Ensure we halt the program on panic (if we don't mention this crate it won't
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// be linked)
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use panic_halt as _;
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// A shorter alias for the Peripheral Access Crate, which provides low-level
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// register access
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use pico::hal::pac;
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// A shorter alias for the Hardware Abstraction Layer, which provides
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// higher-level drivers.
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use pico::hal;
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//// The linker will place this boot block at the start of our program image. We
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//// need this to help the ROM bootloader get our code up and running.
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#[link_section = ".boot2"]
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#[used]
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pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER;
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/// Entry point to our bare-metal application.
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///
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/// The `#[entry]` macro ensures the Cortex-M start-up code calls this function
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/// as soon as all global variables are initialised.
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///
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/// The function configures the RP2040 peripherals, then just reads the button
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/// and sets the LED appropriately.
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#[entry]
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fn main() -> ! {
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// Grab our singleton objects
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let mut pac = pac::Peripherals::take().unwrap();
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// Note - we don't do any clock set-up in this example. The RP2040 will run
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// at it's default clock speed.
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// The single-cycle I/O block controls our GPIO pins
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let sio = hal::sio::Sio::new(pac.SIO);
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// Set the pins up according to their function on this particular board
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let pins = pico::Pins::new(
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pac.IO_BANK0,
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pac.PADS_BANK0,
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sio.gpio_bank0,
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&mut pac.RESETS,
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);
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// Our LED output
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let mut led_pin = pins.led.into_push_pull_output();
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// Our button input
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let button_pin = pins.bootsel.into_pull_down_input();
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// Run forever, setting the LED according to the button
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loop {
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if button_pin.is_low().unwrap() {
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led_pin.set_high().unwrap();
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} else {
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led_pin.set_low().unwrap();
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}
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}
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}
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// End of file
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