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bare8.rs 3.33 KiB
//! bare8.rs
//!
//! The RTFM framework
//!
//! What it covers:
//! - utilizing the RTFM framework for serial communication
//! - singletons (entities with a singe instance)
//! - owned resources
//! - peripheral access in RTFM
//! - polling in `idle`
#![no_main]
#![no_std]
extern crate panic_halt;
use cortex_m::iprintln;
use nb::block;
extern crate stm32f4xx_hal as hal;
use crate::hal::prelude::*;
use crate::hal::serial::{config::Config, Rx, Serial, Tx};
use hal::stm32::{ITM, USART2};
use rtfm::app;
#[app(device = hal::stm32, peripherals = true)]
const APP: () = {
struct Resources {
// Late resources
TX: Tx<USART2>,
RX: Rx<USART2>,
ITM: ITM,
}
// init runs in an interrupt free section
#[init]
fn init(cx: init::Context) -> init::LateResources {
let mut core = cx.core;
let device = cx.device;
let stim = &mut core.ITM.stim[0];
iprintln!(stim, "bare8");
let rcc = device.RCC.constrain();
// 16 MHz (default, all clocks)
let clocks = rcc.cfgr.freeze();
let gpioa = device.GPIOA.split();
let tx = gpioa.pa2.into_alternate_af7();
let rx = gpioa.pa3.into_alternate_af7();
let serial = Serial::usart2(
device.USART2,
(tx, rx),
Config::default().baudrate(115_200.bps()),
clocks,
)
.unwrap();
// Separate out the sender and receiver of the serial port
let (tx, rx) = serial.split();
// Late resources
init::LateResources {
TX: tx,
RX: rx,
ITM: core.ITM,
}
}
// idle may be interrupted by other interrupts/tasks in the system
#[idle(resources = [RX, TX, ITM])]
fn idle(cx: idle::Context) -> ! {
let rx = cx.resources.RX;
let tx = cx.resources.TX;
let stim = &mut cx.resources.ITM.stim[0];
loop {
match block!(rx.read()) {
Ok(byte) => {
iprintln!(stim, "Ok {:?}", byte);
tx.write(byte).unwrap();
}
Err(err) => {
iprintln!(stim, "Error {:?}", err);
}
}
}
}
};
// Optional assignment
// 0. Compile and run the example. Notice, we use the default 16MHz clock.
//
// > cargo build --example bare8 --features "rtfm"
// (or use the vscode build task)
//
// 1. What is the behavior in comparison to bare7.4 and bare7.5
//
// ** your answer here **
//
// Commit your answer (bare8_1)
//
// 2. Add a local variable `received` that counts the number of bytes received.
// Add a local variable `errors` that counts the number of errors.
//
// Adjust the ITM trace to include the additional information.
//
// Commit your development (bare8_2)
//
// 3. The added tracing, how did that effect the performance,
// (are you know loosing more data)?
//
// ** your answer here **
//
// Commit your answer (bare8_3)
//
// 4. *Optional
// Compile and run the program in release mode.
// If using vscode, look at the `.vscode` folder `task.json` and `launch.json`,
// you may need to add a new "profile" (a bit of copy paste).
//
// How did the optimized build compare to the debug build (performance/lost bytes)
//
// ** your answer here **
//
// Commit your answer (bare8_4)