diff --git a/embassy-nrf/src/chips/nrf52810.rs b/embassy-nrf/src/chips/nrf52810.rs
index faa52d8fb..3e500098c 100644
--- a/embassy-nrf/src/chips/nrf52810.rs
+++ b/embassy-nrf/src/chips/nrf52810.rs
@@ -128,6 +128,9 @@ embassy_hal_common::peripherals! {
// QDEC
QDEC,
+
+ // PDM
+ PDM,
}
impl_uarte!(UARTE0, UARTE0, UARTE0_UART0);
diff --git a/embassy-nrf/src/chips/nrf52811.rs b/embassy-nrf/src/chips/nrf52811.rs
index bbdf1cbe5..25c7c0d91 100644
--- a/embassy-nrf/src/chips/nrf52811.rs
+++ b/embassy-nrf/src/chips/nrf52811.rs
@@ -128,6 +128,9 @@ embassy_hal_common::peripherals! {
// QDEC
QDEC,
+
+ // PDM
+ PDM,
}
impl_uarte!(UARTE0, UARTE0, UARTE0_UART0);
diff --git a/embassy-nrf/src/chips/nrf52833.rs b/embassy-nrf/src/chips/nrf52833.rs
index 39a0f93f9..3b33907d2 100644
--- a/embassy-nrf/src/chips/nrf52833.rs
+++ b/embassy-nrf/src/chips/nrf52833.rs
@@ -158,6 +158,9 @@ embassy_hal_common::peripherals! {
// QDEC
QDEC,
+
+ // PDM
+ PDM,
}
#[cfg(feature = "nightly")]
diff --git a/embassy-nrf/src/chips/nrf52840.rs b/embassy-nrf/src/chips/nrf52840.rs
index e3d8f34a1..ae59f8b25 100644
--- a/embassy-nrf/src/chips/nrf52840.rs
+++ b/embassy-nrf/src/chips/nrf52840.rs
@@ -161,6 +161,9 @@ embassy_hal_common::peripherals! {
// TEMP
TEMP,
+
+ // PDM
+ PDM,
}
#[cfg(feature = "nightly")]
diff --git a/embassy-nrf/src/chips/nrf9160.rs b/embassy-nrf/src/chips/nrf9160.rs
index a4be8564e..f8ed11e03 100644
--- a/embassy-nrf/src/chips/nrf9160.rs
+++ b/embassy-nrf/src/chips/nrf9160.rs
@@ -260,6 +260,9 @@ embassy_hal_common::peripherals! {
P0_29,
P0_30,
P0_31,
+
+ // PDM
+ PDM,
}
impl_uarte!(UARTETWISPI0, UARTE0, UARTE0_SPIM0_SPIS0_TWIM0_TWIS0);
diff --git a/embassy-nrf/src/lib.rs b/embassy-nrf/src/lib.rs
index d7bd21702..bc70fc2f6 100644
--- a/embassy-nrf/src/lib.rs
+++ b/embassy-nrf/src/lib.rs
@@ -76,6 +76,14 @@ pub mod gpio;
pub mod gpiote;
#[cfg(not(any(feature = "_nrf5340", feature = "_nrf9160")))]
pub mod nvmc;
+#[cfg(any(
+ feature = "nrf52810",
+ feature = "nrf52811",
+ feature = "nrf52833",
+ feature = "nrf52840",
+ feature = "_nrf9160"
+))]
+pub mod pdm;
pub mod ppi;
#[cfg(not(any(feature = "nrf52805", feature = "nrf52820", feature = "_nrf5340-net")))]
pub mod pwm;
diff --git a/embassy-nrf/src/pdm.rs b/embassy-nrf/src/pdm.rs
new file mode 100644
index 000000000..b7c7022cf
--- /dev/null
+++ b/embassy-nrf/src/pdm.rs
@@ -0,0 +1,242 @@
+//! PDM mirophone interface
+
+use core::marker::PhantomData;
+use core::sync::atomic::{compiler_fence, Ordering};
+use core::task::Poll;
+
+use embassy_hal_common::drop::OnDrop;
+use embassy_hal_common::{into_ref, PeripheralRef};
+use embassy_sync::waitqueue::AtomicWaker;
+use futures::future::poll_fn;
+
+use crate::chip::EASY_DMA_SIZE;
+use crate::gpio::sealed::Pin;
+use crate::gpio::{AnyPin, Pin as GpioPin};
+use crate::interrupt::{self, InterruptExt};
+use crate::peripherals::PDM;
+use crate::{pac, Peripheral};
+
+/// PDM microphone interface
+pub struct Pdm<'d> {
+ irq: PeripheralRef<'d, interrupt::PDM>,
+ phantom: PhantomData<&'d PDM>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+#[non_exhaustive]
+pub enum Error {
+ BufferTooLong,
+ BufferZeroLength,
+ NotRunning,
+}
+
+static WAKER: AtomicWaker = AtomicWaker::new();
+static DUMMY_BUFFER: [i16; 1] = [0; 1];
+
+impl<'d> Pdm<'d> {
+ /// Create PDM driver
+ pub fn new(
+ pdm: impl Peripheral<P = PDM> + 'd,
+ irq: impl Peripheral<P = interrupt::PDM> + 'd,
+ clk: impl Peripheral<P = impl GpioPin> + 'd,
+ din: impl Peripheral<P = impl GpioPin> + 'd,
+ config: Config,
+ ) -> Self {
+ into_ref!(clk, din);
+ Self::new_inner(pdm, irq, clk.map_into(), din.map_into(), config)
+ }
+
+ fn new_inner(
+ _pdm: impl Peripheral<P = PDM> + 'd,
+ irq: impl Peripheral<P = interrupt::PDM> + 'd,
+ clk: PeripheralRef<'d, AnyPin>,
+ din: PeripheralRef<'d, AnyPin>,
+ config: Config,
+ ) -> Self {
+ into_ref!(irq);
+
+ let r = Self::regs();
+
+ // setup gpio pins
+ din.conf().write(|w| w.input().set_bit());
+ r.psel.din.write(|w| unsafe { w.bits(din.psel_bits()) });
+ clk.set_low();
+ clk.conf().write(|w| w.dir().output());
+ r.psel.clk.write(|w| unsafe { w.bits(clk.psel_bits()) });
+
+ // configure
+ // use default for
+ // - gain right
+ // - gain left
+ // - clk
+ // - ratio
+ r.mode.write(|w| {
+ w.edge().bit(config.edge == Edge::LeftRising);
+ w.operation().bit(config.operation_mode == OperationMode::Mono);
+ w
+ });
+ r.gainl.write(|w| w.gainl().default_gain());
+ r.gainr.write(|w| w.gainr().default_gain());
+
+ // IRQ
+ irq.disable();
+ irq.set_handler(|_| {
+ let r = Self::regs();
+ r.intenclr.write(|w| w.end().clear());
+ WAKER.wake();
+ });
+ irq.enable();
+
+ r.enable.write(|w| w.enable().set_bit());
+
+ Self {
+ phantom: PhantomData,
+ irq,
+ }
+ }
+
+ /// Start sampling microphon data into a dummy buffer
+ /// Usefull to start the microphon and keep it active between recording samples
+ pub async fn start(&mut self) {
+ let r = Self::regs();
+
+ // start dummy sampling because microphon needs some setup time
+ r.sample
+ .ptr
+ .write(|w| unsafe { w.sampleptr().bits(DUMMY_BUFFER.as_ptr() as u32) });
+ r.sample
+ .maxcnt
+ .write(|w| unsafe { w.buffsize().bits(DUMMY_BUFFER.len() as _) });
+
+ r.tasks_start.write(|w| w.tasks_start().set_bit());
+ }
+
+ /// Stop sampling microphon data inta a dummy buffer
+ pub async fn stop(&mut self) {
+ let r = Self::regs();
+ r.tasks_stop.write(|w| w.tasks_stop().set_bit());
+ r.events_started.reset();
+ }
+
+ pub async fn sample(&mut self, buffer: &mut [i16]) -> Result<(), Error> {
+ if buffer.len() == 0 {
+ return Err(Error::BufferZeroLength);
+ }
+ if buffer.len() > EASY_DMA_SIZE {
+ return Err(Error::BufferTooLong);
+ }
+
+ let r = Self::regs();
+
+ if r.events_started.read().events_started().bit_is_clear() {
+ return Err(Error::NotRunning);
+ }
+
+ let drop = OnDrop::new(move || {
+ r.intenclr.write(|w| w.end().clear());
+ r.events_stopped.reset();
+
+ // reset to dummy buffer
+ r.sample
+ .ptr
+ .write(|w| unsafe { w.sampleptr().bits(DUMMY_BUFFER.as_ptr() as u32) });
+ r.sample
+ .maxcnt
+ .write(|w| unsafe { w.buffsize().bits(DUMMY_BUFFER.len() as _) });
+
+ while r.events_stopped.read().bits() == 0 {}
+ });
+
+ // setup user buffer
+ let ptr = buffer.as_ptr();
+ let len = buffer.len();
+ r.sample.ptr.write(|w| unsafe { w.sampleptr().bits(ptr as u32) });
+ r.sample.maxcnt.write(|w| unsafe { w.buffsize().bits(len as _) });
+
+ // wait till the current sample is finished and the user buffer sample is started
+ Self::wait_for_sample().await;
+
+ // reset the buffer back to the dummy buffer
+ r.sample
+ .ptr
+ .write(|w| unsafe { w.sampleptr().bits(DUMMY_BUFFER.as_ptr() as u32) });
+ r.sample
+ .maxcnt
+ .write(|w| unsafe { w.buffsize().bits(DUMMY_BUFFER.len() as _) });
+
+ // wait till the user buffer is sampled
+ Self::wait_for_sample().await;
+
+ drop.defuse();
+
+ Ok(())
+ }
+
+ async fn wait_for_sample() {
+ let r = Self::regs();
+
+ r.events_end.reset();
+ r.intenset.write(|w| w.end().set());
+
+ compiler_fence(Ordering::SeqCst);
+
+ poll_fn(|cx| {
+ WAKER.register(cx.waker());
+ if r.events_end.read().events_end().bit_is_set() {
+ return Poll::Ready(());
+ }
+ Poll::Pending
+ })
+ .await;
+
+ compiler_fence(Ordering::SeqCst);
+ }
+
+ fn regs() -> &'static pac::pdm::RegisterBlock {
+ unsafe { &*pac::PDM::ptr() }
+ }
+}
+
+/// PDM microphone driver Config
+pub struct Config {
+ /// Use stero or mono operation
+ pub operation_mode: OperationMode,
+ /// On which edge the left channel should be samples
+ pub edge: Edge,
+}
+
+impl Default for Config {
+ fn default() -> Self {
+ Self {
+ operation_mode: OperationMode::Mono,
+ edge: Edge::LeftFalling,
+ }
+ }
+}
+
+#[derive(PartialEq)]
+pub enum OperationMode {
+ Mono,
+ Stereo,
+}
+#[derive(PartialEq)]
+pub enum Edge {
+ LeftRising,
+ LeftFalling,
+}
+
+impl<'d> Drop for Pdm<'d> {
+ fn drop(&mut self) {
+ let r = Self::regs();
+
+ r.tasks_stop.write(|w| w.tasks_stop().set_bit());
+
+ self.irq.disable();
+
+ r.enable.write(|w| w.enable().disabled());
+
+ r.psel.din.reset();
+ r.psel.clk.reset();
+ }
+}
diff --git a/examples/nrf/src/bin/pdm.rs b/examples/nrf/src/bin/pdm.rs
new file mode 100644
index 000000000..7388580fb
--- /dev/null
+++ b/examples/nrf/src/bin/pdm.rs
@@ -0,0 +1,33 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::info;
+use embassy_executor::Spawner;
+use embassy_nrf::interrupt;
+use embassy_nrf::pdm::{Config, Pdm};
+use embassy_time::{Duration, Timer};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_p: Spawner) {
+ let p = embassy_nrf::init(Default::default());
+ let config = Config::default();
+ let mut pdm = Pdm::new(p.PDM, interrupt::take!(PDM), p.P0_01, p.P0_00, config);
+
+ loop {
+ pdm.start().await;
+
+ // wait some time till the microphon settled
+ Timer::after(Duration::from_millis(1000)).await;
+
+ const SAMPLES: usize = 2048;
+ let mut buf = [0i16; SAMPLES];
+ pdm.sample(&mut buf).await.unwrap();
+
+ info!("samples: {:?}", &buf);
+
+ pdm.stop().await;
+ Timer::after(Duration::from_millis(100)).await;
+ }
+}