va108xx-rs/examples/rtic/src/bin/uart-echo-rtic.rs

132 lines
3.7 KiB
Rust

//! More complex UART application
//!
//! Uses the IRQ capabilities of the VA10820 peripheral and the RTIC framework to poll the UART in
//! a non-blocking way. All received data will be sent back to the sender.
#![no_main]
#![no_std]
use ringbuf::StaticRb;
// Larger buffer for TC to be able to hold the possibly large memory write packets.
const RX_RING_BUF_SIZE: usize = 1024;
#[rtic::app(device = pac, dispatchers = [OC4])]
mod app {
use super::*;
use embedded_io::Write;
use panic_rtt_target as _;
use ringbuf::traits::{Consumer, Observer, Producer};
use rtic_example::SYSCLK_FREQ;
use rtic_monotonics::Monotonic;
use rtt_target::{rprintln, rtt_init_print};
use va108xx_hal::{
gpio::PinsA,
pac,
prelude::*,
uart::{self, RxWithInterrupt, Tx},
InterruptConfig,
};
#[local]
struct Local {
rx: RxWithInterrupt<pac::Uarta>,
tx: Tx<pac::Uarta>,
}
#[shared]
struct Shared {
rb: StaticRb<u8, RX_RING_BUF_SIZE>,
}
rtic_monotonics::systick_monotonic!(Mono, 1_000);
#[init]
fn init(cx: init::Context) -> (Shared, Local) {
rtt_init_print!();
rprintln!("-- VA108xx UART Echo with IRQ example application--");
Mono::start(cx.core.SYST, SYSCLK_FREQ.raw());
let mut dp = cx.device;
let gpioa = PinsA::new(&mut dp.sysconfig, dp.porta);
let tx = gpioa.pa9.into_funsel_2();
let rx = gpioa.pa8.into_funsel_2();
let irq_uart = uart::Uart::new_with_interrupt(
&mut dp.sysconfig,
SYSCLK_FREQ,
dp.uarta,
(tx, rx),
115200.Hz(),
InterruptConfig::new(pac::Interrupt::OC3, true, true),
);
let (tx, rx) = irq_uart.split();
let mut rx = rx.into_rx_with_irq();
rx.start();
echo_handler::spawn().unwrap();
(
Shared {
rb: StaticRb::default(),
},
Local { rx, tx },
)
}
// `shared` cannot be accessed from this context
#[idle]
fn idle(_cx: idle::Context) -> ! {
loop {
cortex_m::asm::nop();
}
}
#[task(
binds = OC3,
shared = [rb],
local = [
rx,
],
)]
fn reception_task(mut cx: reception_task::Context) {
let mut buf: [u8; 16] = [0; 16];
let mut ringbuf_full = false;
let result = cx.local.rx.on_interrupt(&mut buf);
if result.bytes_read > 0 && result.errors.is_none() {
cx.shared.rb.lock(|rb| {
if rb.vacant_len() < result.bytes_read {
ringbuf_full = true;
} else {
rb.push_slice(&buf[0..result.bytes_read]);
}
});
}
if ringbuf_full {
// Could also drop oldest data, but that would require the consumer to be shared.
rprintln!("buffer full, data was dropped");
}
}
#[task(shared = [rb], local = [
buf: [u8; RX_RING_BUF_SIZE] = [0; RX_RING_BUF_SIZE],
tx
], priority=1)]
async fn echo_handler(mut cx: echo_handler::Context) {
loop {
cx.shared.rb.lock(|rb| {
let bytes_to_read = rb.occupied_len();
if bytes_to_read > 0 {
let actual_read_bytes = rb.pop_slice(&mut cx.local.buf[0..bytes_to_read]);
cx.local
.tx
.write_all(&cx.local.buf[0..actual_read_bytes])
.expect("Failed to write to TX");
}
});
Mono::delay(50.millis()).await;
}
}
}