Module stm32f103xx_hal::examples::_04_serial

Serial interface loopback test

You have to short the TX and RX pins to make this program work

 
#![deny(unsafe_code)]
#![deny(warnings)]
#![no_std]
 
extern crate cortex_m;
#[macro_use(block)]
extern crate nb;
extern crate panic_abort;
extern crate stm32f103xx_hal as hal;
 
use cortex_m::asm;
use hal::prelude::*;
use hal::serial::Serial;
use hal::stm32f103xx;
 
fn main() {
    let p = stm32f103xx::Peripherals::take().unwrap();
 
    let mut flash = p.FLASH.constrain();
    let mut rcc = p.RCC.constrain();
 
    let clocks = rcc.cfgr.freeze(&mut flash.acr);
 
    let mut afio = p.AFIO.constrain(&mut rcc.apb2);
 
    // let mut gpioa = p.GPIOA.split(&mut rcc.apb2);
    let mut gpiob = p.GPIOB.split(&mut rcc.apb2);
 
    // USART1
    // let tx = gpioa.pa9.into_alternate_push_pull(&mut gpioa.crh);
    // let rx = gpioa.pa10;
 
    // USART1
    // let tx = gpiob.pb6.into_alternate_push_pull(&mut gpiob.crl);
    // let rx = gpiob.pb7;
 
    // USART2
    // let tx = gpioa.pa2.into_alternate_push_pull(&mut gpioa.crl);
    // let rx = gpioa.pa3;
 
    // USART3
    let tx = gpiob.pb10.into_alternate_push_pull(&mut gpiob.crh);
    let rx = gpiob.pb11;
 
    let serial = Serial::usart3(
        p.USART3,
        (tx, rx),
        &mut afio.mapr,
        9_600.bps(),
        clocks,
        &mut rcc.apb1,
    );
 
    let (mut tx, mut rx) = serial.split();
 
    let sent = b'X';
 
    block!(tx.write(sent)).ok();
 
    let received = block!(rx.read()).unwrap();
 
    assert_eq!(received, sent);
 
    asm::bkpt();
}