42 lines
1.1 KiB
Rust
42 lines
1.1 KiB
Rust
//! Sends "Hello, world!" through the ITM port 0
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//!
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//! **IMPORTANT** Not all Cortex-M chips support ITM. You'll have to connect the
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//! microcontroller's SWO pin to the SWD interface. Note that some development
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//! boards don't provide this option.
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//!
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//! ITM is much faster than semihosting. Like 4 orders of magnitude or so.
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//!
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//! You'll need [`itmdump`] to receive the message on the host plus you'll need
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//! to uncomment OpenOCD's ITM support in `.gdbinit`.
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//!
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//! [`itmdump`]: https://docs.rs/itm/0.1.1/itm/
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#![feature(used)]
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#![no_std]
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#[macro_use]
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extern crate cortex_m;
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extern crate cortex_m_rt;
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use cortex_m::{asm, interrupt, peripheral};
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fn main() {
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interrupt::free(
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|cs| {
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let itm = peripheral::ITM.borrow(&cs);
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iprintln!(&itm.stim[0], "Hello, world!");
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},
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);
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}
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// As we are not using interrupts, we just register a dummy catch all handler
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#[allow(dead_code)]
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#[used]
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#[link_section = ".rodata.interrupts"]
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static INTERRUPTS: [extern "C" fn(); 240] = [default_handler; 240];
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extern "C" fn default_handler() {
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asm::bkpt();
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}
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