//! # GPIO 'Blinky' Example //! //! This application demonstrates how to control a GPIO pin on the RP2040. //! //! It may need to be adapted to your particular board layout and/or pin assignment. //! //! See the `Cargo.toml` file for Copyright and licence 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 _; // Alias for our HAL crate use rp2040_hal as hal; // A shorter alias for the Peripheral Access Crate, which provides low-level // register access use hal::pac; // Some traits we need use embedded_hal::digital::v2::InputPin; use embedded_hal::digital::v2::OutputPin; use embedded_time::fixed_point::FixedPoint; use hal::gpio::dynpin::DynPin; use hal::Clock; /// 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_W25Q080; /// External high-speed crystal on the Raspberry Pi Pico board is 12 MHz. Adjust /// if your board has a different frequency const XTAL_FREQ_HZ: u32 = 12_000_000u32; use dht11::Dht11; struct InOutPin { inner: DynPin, } impl InputPin for InOutPin { type Error = rp2040_hal::gpio::Error; fn is_high(&self) -> Result::Error> { self.inner.is_high() } fn is_low(&self) -> Result::Error> { self.inner.is_low() } } impl OutputPin for InOutPin { type Error = rp2040_hal::gpio::Error; fn set_low(&mut self) -> Result<(), ::Error> { self.inner.into_readable_output(); self.inner.set_low() } fn set_high(&mut self) -> Result<(), ::Error> { self.inner.into_pull_up_input(); Ok(()) } } /// 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 toggles a GPIO pin in /// an infinite loop. If there is an LED connected to that pin, it will blink. #[entry] fn main() -> ! { // Grab our singleton objects let mut pac = pac::Peripherals::take().unwrap(); let core = pac::CorePeripherals::take().unwrap(); // Set up the watchdog driver - needed by the clock setup code let mut watchdog = hal::Watchdog::new(pac.WATCHDOG); // Configure the clocks let clocks = hal::clocks::init_clocks_and_plls( XTAL_FREQ_HZ, 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 = hal::Sio::new(pac.SIO); // Set the pins to their default state let pins = hal::gpio::Pins::new( pac.IO_BANK0, pac.PADS_BANK0, sio.gpio_bank0, &mut pac.RESETS, ); let mut delay = cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().integer()); // Configure GPIO 25 as an output let pin = pins.gpio0.into_push_pull_output(); let pin = InOutPin { inner: pin.into() }; // Create an instance of the DHT11 device let mut dht11 = Dht11::new(pin); // Perform a sensor reading let _measurement = dht11.perform_measurement(&mut delay).unwrap(); #[allow(clippy::empty_loop)] loop { // Empty loop } } // End of file