diff --git a/embassy-nrf/src/uarte.rs b/embassy-nrf/src/uarte.rs index d9959911..636d6c7a 100644 --- a/embassy-nrf/src/uarte.rs +++ b/embassy-nrf/src/uarte.rs @@ -173,6 +173,61 @@ impl<'d, T: Instance> Uarte<'d, T> { (self.tx, self.rx) } + /// Split the Uarte into a transmitter and receiver that will + /// return on idle, which is determined as the time it takes + /// for two bytes to be received. + pub fn split_with_idle( + self, + timer: impl Peripheral

+ 'd, + ppi_ch1: impl Peripheral

+ 'd, + ppi_ch2: impl Peripheral

+ 'd, + ) -> (UarteTx<'d, T>, UarteRxWithIdle<'d, T, U>) { + let mut timer = Timer::new(timer); + + into_ref!(ppi_ch1, ppi_ch2); + + let r = T::regs(); + + // BAUDRATE register values are `baudrate * 2^32 / 16000000` + // source: https://devzone.nordicsemi.com/f/nordic-q-a/391/uart-baudrate-register-values + // + // We want to stop RX if line is idle for 2 bytes worth of time + // That is 20 bits (each byte is 1 start bit + 8 data bits + 1 stop bit) + // This gives us the amount of 16M ticks for 20 bits. + let baudrate = r.baudrate.read().baudrate().variant().unwrap(); + let timeout = 0x8000_0000 / (baudrate as u32 / 40); + + timer.set_frequency(Frequency::F16MHz); + timer.cc(0).write(timeout); + timer.cc(0).short_compare_clear(); + timer.cc(0).short_compare_stop(); + + let mut ppi_ch1 = Ppi::new_one_to_two( + ppi_ch1.map_into(), + Event::from_reg(&r.events_rxdrdy), + timer.task_clear(), + timer.task_start(), + ); + ppi_ch1.enable(); + + let mut ppi_ch2 = Ppi::new_one_to_one( + ppi_ch2.map_into(), + timer.cc(0).event_compare(), + Task::from_reg(&r.tasks_stoprx), + ); + ppi_ch2.enable(); + + ( + self.tx, + UarteRxWithIdle { + rx: self.rx, + timer, + ppi_ch1: ppi_ch1, + _ppi_ch2: ppi_ch2, + }, + ) + } + /// Return the endtx event for use with PPI pub fn event_endtx(&self) -> Event { let r = T::regs(); @@ -597,6 +652,117 @@ impl<'a, T: Instance> Drop for UarteRx<'a, T> { } } +pub struct UarteRxWithIdle<'d, T: Instance, U: TimerInstance> { + rx: UarteRx<'d, T>, + timer: Timer<'d, U>, + ppi_ch1: Ppi<'d, AnyConfigurableChannel, 1, 2>, + _ppi_ch2: Ppi<'d, AnyConfigurableChannel, 1, 1>, +} + +impl<'d, T: Instance, U: TimerInstance> UarteRxWithIdle<'d, T, U> { + pub async fn read(&mut self, buffer: &mut [u8]) -> Result<(), Error> { + self.ppi_ch1.disable(); + self.rx.read(buffer).await + } + + pub fn blocking_read(&mut self, buffer: &mut [u8]) -> Result<(), Error> { + self.ppi_ch1.disable(); + self.rx.blocking_read(buffer) + } + + pub async fn read_until_idle(&mut self, buffer: &mut [u8]) -> Result { + if buffer.len() == 0 { + return Err(Error::BufferZeroLength); + } + if buffer.len() > EASY_DMA_SIZE { + return Err(Error::BufferTooLong); + } + + let ptr = buffer.as_ptr(); + let len = buffer.len(); + + let r = T::regs(); + let s = T::state(); + + self.ppi_ch1.enable(); + + let drop = OnDrop::new(|| { + self.timer.stop(); + + r.intenclr.write(|w| w.endrx().clear()); + r.events_rxto.reset(); + r.tasks_stoprx.write(|w| unsafe { w.bits(1) }); + + while r.events_endrx.read().bits() == 0 {} + }); + + r.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) }); + r.rxd.maxcnt.write(|w| unsafe { w.maxcnt().bits(len as _) }); + + r.events_endrx.reset(); + r.intenset.write(|w| w.endrx().set()); + + compiler_fence(Ordering::SeqCst); + + r.tasks_startrx.write(|w| unsafe { w.bits(1) }); + + poll_fn(|cx| { + s.endrx_waker.register(cx.waker()); + if r.events_endrx.read().bits() != 0 { + return Poll::Ready(()); + } + Poll::Pending + }) + .await; + + compiler_fence(Ordering::SeqCst); + let n = r.rxd.amount.read().amount().bits() as usize; + + self.timer.stop(); + r.events_rxstarted.reset(); + + drop.defuse(); + + Ok(n) + } + + pub fn blocking_read_until_idle(&mut self, buffer: &mut [u8]) -> Result { + if buffer.len() == 0 { + return Err(Error::BufferZeroLength); + } + if buffer.len() > EASY_DMA_SIZE { + return Err(Error::BufferTooLong); + } + + let ptr = buffer.as_ptr(); + let len = buffer.len(); + + let r = T::regs(); + + self.ppi_ch1.enable(); + + r.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) }); + r.rxd.maxcnt.write(|w| unsafe { w.maxcnt().bits(len as _) }); + + r.events_endrx.reset(); + r.intenclr.write(|w| w.endrx().clear()); + + compiler_fence(Ordering::SeqCst); + + r.tasks_startrx.write(|w| unsafe { w.bits(1) }); + + while r.events_endrx.read().bits() == 0 {} + + compiler_fence(Ordering::SeqCst); + let n = r.rxd.amount.read().amount().bits() as usize; + + self.timer.stop(); + r.events_rxstarted.reset(); + + Ok(n) + } +} + #[cfg(not(any(feature = "_nrf9160", feature = "nrf5340")))] pub(crate) fn apply_workaround_for_enable_anomaly(_r: &crate::pac::uarte0::RegisterBlock) { // Do nothing @@ -665,270 +831,6 @@ pub(crate) fn drop_tx_rx(r: &pac::uarte0::RegisterBlock, s: &sealed::State) { } } -/// Interface to an UARTE peripheral that uses an additional timer and two PPI channels, -/// allowing it to implement the ReadUntilIdle trait. -pub struct UarteWithIdle<'d, U: Instance, T: TimerInstance> { - tx: UarteTx<'d, U>, - rx: UarteRxWithIdle<'d, U, T>, -} - -impl<'d, U: Instance, T: TimerInstance> UarteWithIdle<'d, U, T> { - /// Create a new UARTE without hardware flow control - pub fn new( - uarte: impl Peripheral

+ 'd, - timer: impl Peripheral

+ 'd, - ppi_ch1: impl Peripheral

+ 'd, - ppi_ch2: impl Peripheral

+ 'd, - irq: impl Peripheral

+ 'd, - rxd: impl Peripheral

+ 'd, - txd: impl Peripheral

+ 'd, - config: Config, - ) -> Self { - into_ref!(rxd, txd); - Self::new_inner( - uarte, - timer, - ppi_ch1, - ppi_ch2, - irq, - rxd.map_into(), - txd.map_into(), - None, - None, - config, - ) - } - - /// Create a new UARTE with hardware flow control (RTS/CTS) - pub fn new_with_rtscts( - uarte: impl Peripheral

+ 'd, - timer: impl Peripheral

+ 'd, - ppi_ch1: impl Peripheral

+ 'd, - ppi_ch2: impl Peripheral

+ 'd, - irq: impl Peripheral

+ 'd, - rxd: impl Peripheral

+ 'd, - txd: impl Peripheral

+ 'd, - cts: impl Peripheral

+ 'd, - rts: impl Peripheral

+ 'd, - config: Config, - ) -> Self { - into_ref!(rxd, txd, cts, rts); - Self::new_inner( - uarte, - timer, - ppi_ch1, - ppi_ch2, - irq, - rxd.map_into(), - txd.map_into(), - Some(cts.map_into()), - Some(rts.map_into()), - config, - ) - } - - fn new_inner( - uarte: impl Peripheral

+ 'd, - timer: impl Peripheral

+ 'd, - ppi_ch1: impl Peripheral

+ 'd, - ppi_ch2: impl Peripheral

+ 'd, - irq: impl Peripheral

+ 'd, - rxd: PeripheralRef<'d, AnyPin>, - txd: PeripheralRef<'d, AnyPin>, - cts: Option>, - rts: Option>, - config: Config, - ) -> Self { - let baudrate = config.baudrate; - let (tx, rx) = Uarte::new_inner(uarte, irq, rxd, txd, cts, rts, config).split(); - - let mut timer = Timer::new(timer); - - into_ref!(ppi_ch1, ppi_ch2); - - let r = U::regs(); - - // BAUDRATE register values are `baudrate * 2^32 / 16000000` - // source: https://devzone.nordicsemi.com/f/nordic-q-a/391/uart-baudrate-register-values - // - // We want to stop RX if line is idle for 2 bytes worth of time - // That is 20 bits (each byte is 1 start bit + 8 data bits + 1 stop bit) - // This gives us the amount of 16M ticks for 20 bits. - let timeout = 0x8000_0000 / (baudrate as u32 / 40); - - timer.set_frequency(Frequency::F16MHz); - timer.cc(0).write(timeout); - timer.cc(0).short_compare_clear(); - timer.cc(0).short_compare_stop(); - - let mut ppi_ch1 = Ppi::new_one_to_two( - ppi_ch1.map_into(), - Event::from_reg(&r.events_rxdrdy), - timer.task_clear(), - timer.task_start(), - ); - ppi_ch1.enable(); - - let mut ppi_ch2 = Ppi::new_one_to_one( - ppi_ch2.map_into(), - timer.cc(0).event_compare(), - Task::from_reg(&r.tasks_stoprx), - ); - ppi_ch2.enable(); - - Self { - tx, - rx: UarteRxWithIdle { - rx, - timer, - ppi_ch1: ppi_ch1, - _ppi_ch2: ppi_ch2, - }, - } - } - - /// Split the Uarte into a transmitter and receiver, which is - /// particuarly useful when having two tasks correlating to - /// transmitting and receiving. - pub fn split(self) -> (UarteTx<'d, U>, UarteRxWithIdle<'d, U, T>) { - (self.tx, self.rx) - } - - pub async fn read(&mut self, buffer: &mut [u8]) -> Result<(), Error> { - self.rx.read(buffer).await - } - - pub async fn write(&mut self, buffer: &[u8]) -> Result<(), Error> { - self.tx.write(buffer).await - } - - pub fn blocking_read(&mut self, buffer: &mut [u8]) -> Result<(), Error> { - self.rx.blocking_read(buffer) - } - - pub fn blocking_write(&mut self, buffer: &[u8]) -> Result<(), Error> { - self.tx.blocking_write(buffer) - } - - pub async fn read_until_idle(&mut self, buffer: &mut [u8]) -> Result { - self.rx.read_until_idle(buffer).await - } - - pub fn blocking_read_until_idle(&mut self, buffer: &mut [u8]) -> Result { - self.rx.blocking_read_until_idle(buffer) - } -} - -pub struct UarteRxWithIdle<'d, U: Instance, T: TimerInstance> { - rx: UarteRx<'d, U>, - timer: Timer<'d, T>, - ppi_ch1: Ppi<'d, AnyConfigurableChannel, 1, 2>, - _ppi_ch2: Ppi<'d, AnyConfigurableChannel, 1, 1>, -} - -impl<'d, U: Instance, T: TimerInstance> UarteRxWithIdle<'d, U, T> { - pub async fn read(&mut self, buffer: &mut [u8]) -> Result<(), Error> { - self.ppi_ch1.disable(); - self.rx.read(buffer).await - } - - pub fn blocking_read(&mut self, buffer: &mut [u8]) -> Result<(), Error> { - self.ppi_ch1.disable(); - self.rx.blocking_read(buffer) - } - - pub async fn read_until_idle(&mut self, buffer: &mut [u8]) -> Result { - if buffer.len() == 0 { - return Err(Error::BufferZeroLength); - } - if buffer.len() > EASY_DMA_SIZE { - return Err(Error::BufferTooLong); - } - - let ptr = buffer.as_ptr(); - let len = buffer.len(); - - let r = U::regs(); - let s = U::state(); - - self.ppi_ch1.enable(); - - let drop = OnDrop::new(|| { - self.timer.stop(); - - r.intenclr.write(|w| w.endrx().clear()); - r.events_rxto.reset(); - r.tasks_stoprx.write(|w| unsafe { w.bits(1) }); - - while r.events_endrx.read().bits() == 0 {} - }); - - r.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) }); - r.rxd.maxcnt.write(|w| unsafe { w.maxcnt().bits(len as _) }); - - r.events_endrx.reset(); - r.intenset.write(|w| w.endrx().set()); - - compiler_fence(Ordering::SeqCst); - - r.tasks_startrx.write(|w| unsafe { w.bits(1) }); - - poll_fn(|cx| { - s.endrx_waker.register(cx.waker()); - if r.events_endrx.read().bits() != 0 { - return Poll::Ready(()); - } - Poll::Pending - }) - .await; - - compiler_fence(Ordering::SeqCst); - let n = r.rxd.amount.read().amount().bits() as usize; - - self.timer.stop(); - r.events_rxstarted.reset(); - - drop.defuse(); - - Ok(n) - } - - pub fn blocking_read_until_idle(&mut self, buffer: &mut [u8]) -> Result { - if buffer.len() == 0 { - return Err(Error::BufferZeroLength); - } - if buffer.len() > EASY_DMA_SIZE { - return Err(Error::BufferTooLong); - } - - let ptr = buffer.as_ptr(); - let len = buffer.len(); - - let r = U::regs(); - - self.ppi_ch1.enable(); - - r.rxd.ptr.write(|w| unsafe { w.ptr().bits(ptr as u32) }); - r.rxd.maxcnt.write(|w| unsafe { w.maxcnt().bits(len as _) }); - - r.events_endrx.reset(); - r.intenclr.write(|w| w.endrx().clear()); - - compiler_fence(Ordering::SeqCst); - - r.tasks_startrx.write(|w| unsafe { w.bits(1) }); - - while r.events_endrx.read().bits() == 0 {} - - compiler_fence(Ordering::SeqCst); - let n = r.rxd.amount.read().amount().bits() as usize; - - self.timer.stop(); - r.events_rxstarted.reset(); - - Ok(n) - } -} pub(crate) mod sealed { use core::sync::atomic::AtomicU8; @@ -1006,18 +908,6 @@ mod eh02 { Ok(()) } } - - impl<'d, U: Instance, T: TimerInstance> embedded_hal_02::blocking::serial::Write for UarteWithIdle<'d, U, T> { - type Error = Error; - - fn bwrite_all(&mut self, buffer: &[u8]) -> Result<(), Self::Error> { - self.blocking_write(buffer) - } - - fn bflush(&mut self) -> Result<(), Self::Error> { - Ok(()) - } - } } #[cfg(feature = "unstable-traits")] @@ -1067,10 +957,6 @@ mod eh1 { impl<'d, T: Instance> embedded_hal_1::serial::ErrorType for UarteRx<'d, T> { type Error = Error; } - - impl<'d, U: Instance, T: TimerInstance> embedded_hal_1::serial::ErrorType for UarteWithIdle<'d, U, T> { - type Error = Error; - } } #[cfg(all( @@ -1126,26 +1012,4 @@ mod eha { self.read(buffer) } } - - impl<'d, U: Instance, T: TimerInstance> embedded_hal_async::serial::Read for UarteWithIdle<'d, U, T> { - type ReadFuture<'a> = impl Future> + 'a where Self: 'a; - - fn read<'a>(&'a mut self, buffer: &'a mut [u8]) -> Self::ReadFuture<'a> { - self.read(buffer) - } - } - - impl<'d, U: Instance, T: TimerInstance> embedded_hal_async::serial::Write for UarteWithIdle<'d, U, T> { - type WriteFuture<'a> = impl Future> + 'a where Self: 'a; - - fn write<'a>(&'a mut self, buffer: &'a [u8]) -> Self::WriteFuture<'a> { - self.write(buffer) - } - - type FlushFuture<'a> = impl Future> + 'a where Self: 'a; - - fn flush<'a>(&'a mut self) -> Self::FlushFuture<'a> { - async move { Ok(()) } - } - } } diff --git a/examples/nrf/src/bin/uart_idle.rs b/examples/nrf/src/bin/uart_idle.rs index 09ec624c..6af4f709 100644 --- a/examples/nrf/src/bin/uart_idle.rs +++ b/examples/nrf/src/bin/uart_idle.rs @@ -15,7 +15,8 @@ async fn main(_spawner: Spawner) { config.baudrate = uarte::Baudrate::BAUD115200; let irq = interrupt::take!(UARTE0_UART0); - let mut uart = uarte::UarteWithIdle::new(p.UARTE0, p.TIMER0, p.PPI_CH0, p.PPI_CH1, irq, p.P0_08, p.P0_06, config); + let uart = uarte::Uarte::new(p.UARTE0, irq, p.P0_08, p.P0_06, config); + let (mut tx, mut rx) = uart.split_with_idle(p.TIMER0, p.PPI_CH0, p.PPI_CH1); info!("uarte initialized!"); @@ -23,12 +24,12 @@ async fn main(_spawner: Spawner) { let mut buf = [0; 8]; buf.copy_from_slice(b"Hello!\r\n"); - unwrap!(uart.write(&buf).await); + unwrap!(tx.write(&buf).await); info!("wrote hello in uart!"); loop { info!("reading..."); - let n = unwrap!(uart.read_until_idle(&mut buf).await); + let n = unwrap!(rx.read_until_idle(&mut buf).await); info!("got {} bytes", n); } }