Files
embedded-rs/examples/device.rs
2018-04-24 01:24:06 +02:00

96 lines
2.6 KiB
Rust

//! Using a device crate
//!
//! Crates generated using [`svd2rust`] are referred to as device crates. These crates provides an
//! API to access the peripherals of a device. When you depend on one of these crates and the "rt"
//! feature is enabled you don't need link to the cortex-m-rt crate.
//!
//! [`svd2rust`]: https://crates.io/crates/svd2rust
//!
//! Device crates also provide an `interrupt!` macro to register interrupt handlers.
//!
//! This example depends on the [`stm32f103xx`] crate so you'll have to add it to your Cargo.toml.
//!
//! [`stm32f103xx`]: https://crates.io/crates/stm32f103xx
//!
//! ```
//! $ edit Cargo.toml && tail $_
//! [dependencies.stm32f103xx]
//! features = ["rt"]
//! version = "0.9.0"
//! ```
//!
//! ---
#![deny(warnings)]
#![feature(const_fn)]
#![no_std]
extern crate cortex_m;
// extern crate cortex_m_rt; // included in the device crate
extern crate cortex_m_semihosting;
#[macro_use(exception, interrupt)]
extern crate stm32f103xx;
extern crate panic_abort; // panicking behavior
use core::cell::RefCell;
use core::fmt::Write;
use cortex_m::interrupt::{self, Mutex};
use cortex_m::peripheral::syst::SystClkSource;
use cortex_m_semihosting::hio::{self, HStdout};
use stm32f103xx::Interrupt;
static HSTDOUT: Mutex<RefCell<Option<HStdout>>> = Mutex::new(RefCell::new(None));
static NVIC: Mutex<RefCell<Option<cortex_m::peripheral::NVIC>>> = Mutex::new(RefCell::new(None));
fn main() {
let global_p = cortex_m::Peripherals::take().unwrap();
interrupt::free(|cs| {
let hstdout = HSTDOUT.borrow(cs);
if let Ok(fd) = hio::hstdout() {
*hstdout.borrow_mut() = Some(fd);
}
let mut nvic = global_p.NVIC;
nvic.enable(Interrupt::TIM2);
*NVIC.borrow(cs).borrow_mut() = Some(nvic);
let mut syst = global_p.SYST;
syst.set_clock_source(SystClkSource::Core);
syst.set_reload(8_000_000); // 1s
syst.enable_counter();
syst.enable_interrupt();
});
}
exception!(SYS_TICK, tick);
fn tick() {
interrupt::free(|cs| {
let hstdout = HSTDOUT.borrow(cs);
if let Some(hstdout) = hstdout.borrow_mut().as_mut() {
writeln!(*hstdout, "Tick").ok();
}
if let Some(nvic) = NVIC.borrow(cs).borrow_mut().as_mut() {
nvic.set_pending(Interrupt::TIM2);
}
});
}
interrupt!(TIM2, tock, locals: {
tocks: u32 = 0;
});
fn tock(l: &mut TIM2::Locals) {
l.tocks += 1;
interrupt::free(|cs| {
let hstdout = HSTDOUT.borrow(cs);
if let Some(hstdout) = hstdout.borrow_mut().as_mut() {
writeln!(*hstdout, "Tock ({})", l.tocks).ok();
}
});
}