Files
embedded-rs/examples/itm.rs
2018-04-24 01:42:13 +02:00

40 lines
1.1 KiB
Rust

//! Sends "Hello, world!" through the ITM port 0
//!
//! **IMPORTANT** Not all Cortex-M chips support ITM. You'll have to connect the microcontroller's
//! SWO pin to the SWD interface. Note that some development boards don't provide this option.
//!
//! ITM is much faster than semihosting. Like 4 orders of magnitude or so.
//!
//! You'll need [`itmdump`] to receive the message on the host plus you'll need to uncomment the
//! `monitor` commands in the `.gdbinit` file.
//!
//! [`itmdump`]: https://docs.rs/itm/0.2.1/itm/
//!
//! ---
#![feature(used)]
#![no_std]
#[macro_use]
extern crate cortex_m;
extern crate cortex_m_rt;
extern crate panic_abort; // panicking behavior
use cortex_m::{asm, Peripherals};
fn main() {
let p = Peripherals::take().unwrap();
let mut itm = p.ITM;
iprintln!(&mut itm.stim[0], "Hello, world!");
}
// As we are not using interrupts, we just register a dummy catch all handler
#[link_section = ".vector_table.interrupts"]
#[used]
static INTERRUPTS: [extern "C" fn(); 240] = [default_handler; 240];
extern "C" fn default_handler() {
asm::bkpt();
}