lock-free reading

This commit is contained in:
Jörn-Michael Miehe 2024-03-15 12:37:55 +00:00
parent 23cf62e01f
commit 29e343b9c2

View file

@ -20,12 +20,13 @@ mod app {
#[shared] #[shared]
struct Shared { struct Shared {
buffer: Option<&'static mut [u8; 512]>, buffer: &'static mut [u8; 512],
} }
#[local] #[local]
struct Local { struct Local {
tx: Option<dma::TxDma<serial::Tx<pac::USART1>, dma::dma1::C4>>, tx: Option<dma::TxDma<serial::Tx<pac::USART1>, dma::dma1::C4>>,
txbuffer: Option<&'static mut [u8; 512]>,
delay_us: timer::DelayUs<pac::TIM2>, delay_us: timer::DelayUs<pac::TIM2>,
led: gpio::gpioc::PC13<gpio::Output>, led: gpio::gpioc::PC13<gpio::Output>,
} }
@ -71,10 +72,11 @@ mod app {
( (
Shared { Shared {
buffer: Some(singleton!(: [u8; 512] = [0b01010101; 512]).unwrap()), buffer: singleton!(: [u8; 512] = [0b01010101; 512]).unwrap(),
}, },
Local { Local {
tx: Some(serial.tx.with_dma(dma1.4)), tx: Some(serial.tx.with_dma(dma1.4)),
txbuffer: Some(singleton!(: [u8; 512] = [0; 512]).unwrap()),
// Configure timer // Configure timer
delay_us: cx.device.TIM2.delay_us(&clocks), delay_us: cx.device.TIM2.delay_us(&clocks),
@ -87,25 +89,24 @@ mod app {
) )
} }
#[idle(local = [tx, delay_us, led], shared = [buffer])] #[idle(local = [tx, txbuffer, delay_us, led], shared = [&buffer])]
fn idle(mut cx: idle::Context) -> ! { fn idle(cx: idle::Context) -> ! {
let mut tx = cx.local.tx.take().unwrap();
loop { loop {
tx = (cx.shared.buffer).lock(|buffer| { let mut tx = cx.local.tx.take().unwrap();
let buf = buffer.take().unwrap(); let mut txbuffer = cx.local.txbuffer.take().unwrap();
let xfer = tx.write(buf);
cx.local.delay_us.delay(1.secs()); txbuffer.copy_from_slice(*cx.shared.buffer);
cx.local.led.set_high(); let xfer = tx.write(txbuffer);
cx.local.delay_us.delay(1.secs()); cx.local.delay_us.delay(1.secs());
cx.local.led.set_low(); cx.local.led.set_high();
let (buf, tx) = xfer.wait(); cx.local.delay_us.delay(1.secs());
buffer.replace(buf); cx.local.led.set_low();
tx
}); (txbuffer, tx) = xfer.wait();
cx.local.tx.replace(tx);
cx.local.txbuffer.replace(txbuffer);
} }
} }
} }