cargo run

12:20:47 patrickod@finn feather-test main ? cargo run                                                                           1 ↵
   Compiling feather-test v0.1.0 (/home/patrickod/code/lsm6ds33/feather-test)
    Finished dev [optimized + debuginfo] target(s) in 0.31s
     Running `probe-run --chip nRF52840_xxAA target/thumbv7em-none-eabihf/debug/feather-test`
  (HOST) INFO  flashing program (9.29 KiB)
  (HOST) INFO  success!
────────────────────────────────────────────────────────────────────────────────
RTT error: Error communicating with probe: An error with the usage of the probe occured
stack backtrace:
   0: Reset
        at /home/patrickod/.cargo/registry/src/github.com-1ecc6299db9ec823/cortex-m-rt-0.6.13/src/lib.rs:497
Error: bug? LR (0xfa2ef000) didn't have the Thumb bit set

config.toml

[target.'cfg(all(target_arch = "arm", target_os = "none"))']
runner = "probe-run --chip nRF52840_xxAA"
rustflags = [
  "-C", "linker=flip-link",
  "-C", "link-arg=-Tlink.x",
  "-C", "link-arg=-Tdefmt.x",
  # This is needed if your flash or ram addresses are not aligned to 0x10000 in memory.x
  # See https://github.com/rust-embedded/cortex-m-quickstart/pull/95
  "-C", "link-arg=--nmagic",
]

[build]
target = "thumbv7em-none-eabihf" # Cortex-M4F and Cortex-M7F (with FPU)

[alias]
rb = "run --bin"
rrb = "run --release --bin"

mian.rs

#![no_std]
#![no_main]

use core::sync::atomic::{AtomicUsize, Ordering};

use defmt_rtt as _; // global logger
use lsm6ds33::LSM6DS33;
use panic_probe as _;

use nrf52840_hal::{
    gpio::p0::Parts as P0Parts,
    pac::Peripherals,
    twim::{Frequency as TwimFrequency, Pins as TwimPins},
    Twim,
};

// same panicking *behavior* as `panic-probe` but doesn't print a panic message
// this prevents the panic message being printed *twice* when `defmt::panic` is invoked
#[defmt::panic_handler]
fn panic() -> ! {
    cortex_m::asm::udf()
}

#[defmt::timestamp]
fn timestamp() -> u64 {
    static COUNT: AtomicUsize = AtomicUsize::new(0);
    // NOTE(no-CAS) `timestamps` runs with interrupts disabled
    let n = COUNT.load(Ordering::Relaxed);
    COUNT.store(n + 1, Ordering::Relaxed);
    n as u64
}

/// Terminates the application and makes `probe-run` exit with exit-code = 0
pub fn exit() -> ! {
    loop {
        cortex_m::asm::bkpt();
    }
}

#[cortex_m_rt::entry]
fn main() -> ! {
    match inner_main() {
        Ok(()) => cortex_m::peripheral::SCB::sys_reset(),
        Err(e) => panic!(e),
    }
}

fn inner_main() -> Result<(), &'static str> {
    let board = Peripherals::take().ok_or("unable to load board")?;
    let p0 = P0Parts::new(board.P0);

    let scl = p0.p0_11.into_floating_input().degrade();
    let sda = p0.p0_12.into_floating_input().degrade();
    let i2c = Twim::new(board.TWIM0, TwimPins { sda, scl }, TwimFrequency::K100);

    let mut sensor = match LSM6DS33::new(i2c) {
        Ok(lsm6ds33) => lsm6ds33,
        Err(_) => return Err("unable to init LSM6DS33"),
    };

    let who_am_i = match sensor.who_am_i() {
        Ok(id) => id,
        Err(_) => return Err("unable to query who_am_i register"),
    };

    defmt::info!("received who_am_i: {:?}", who_am_i);

    Ok(())
}