diff --git a/embassy-nrf/src/chips/nrf52840.rs b/embassy-nrf/src/chips/nrf52840.rs
index 51c55cd4d..d3272b2e8 100644
--- a/embassy-nrf/src/chips/nrf52840.rs
+++ b/embassy-nrf/src/chips/nrf52840.rs
@@ -173,6 +173,9 @@ embassy_hal_internal::peripherals! {
// I2S
I2S,
+
+ // Radio
+ RADIO,
}
impl_usb!(USBD, USBD, USBD);
@@ -311,6 +314,8 @@ impl_saadc_input!(P0_31, ANALOG_INPUT7);
impl_i2s!(I2S, I2S, I2S);
+impl_radio!(RADIO, RADIO, RADIO);
+
embassy_hal_internal::interrupt_mod!(
POWER_CLOCK,
RADIO,
diff --git a/embassy-nrf/src/lib.rs b/embassy-nrf/src/lib.rs
index 358a7cc27..04a6293a4 100644
--- a/embassy-nrf/src/lib.rs
+++ b/embassy-nrf/src/lib.rs
@@ -45,6 +45,11 @@ pub mod buffered_uarte;
pub mod gpio;
#[cfg(feature = "gpiote")]
pub mod gpiote;
+
+// TODO: tested on other chips
+#[cfg(any(feature = "nrf52840"))]
+pub mod radio;
+
#[cfg(any(feature = "nrf52832", feature = "nrf52833", feature = "nrf52840"))]
pub mod i2s;
pub mod nvmc;
diff --git a/embassy-nrf/src/radio/ble.rs b/embassy-nrf/src/radio/ble.rs
new file mode 100644
index 000000000..24dba582f
--- /dev/null
+++ b/embassy-nrf/src/radio/ble.rs
@@ -0,0 +1,438 @@
+//! Radio driver implementation focused on Bluetooth Low-Energy transmission.
+
+use core::future::poll_fn;
+use core::sync::atomic::{compiler_fence, Ordering};
+use core::task::Poll;
+
+use embassy_hal_internal::drop::OnDrop;
+use embassy_hal_internal::{into_ref, PeripheralRef};
+pub use pac::radio::mode::MODE_A as Mode;
+use pac::radio::pcnf0::PLEN_A as PreambleLength;
+use pac::radio::state::STATE_A as RadioState;
+pub use pac::radio::txpower::TXPOWER_A as TxPower;
+
+use crate::interrupt::typelevel::Interrupt;
+use crate::radio::*;
+use crate::util::slice_in_ram_or;
+
+/// RADIO error.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+#[non_exhaustive]
+pub enum Error {
+ /// Buffer was too long.
+ BufferTooLong,
+ /// Buffer was to short.
+ BufferTooShort,
+ /// The buffer is not in data RAM. It is most likely in flash, and nRF's DMA cannot access flash.
+ BufferNotInRAM,
+}
+
+/// Radio driver.
+pub struct Radio<'d, T: Instance> {
+ _p: PeripheralRef<'d, T>,
+}
+
+impl<'d, T: Instance> Radio<'d, T> {
+ /// Create a new radio driver.
+ pub fn new(
+ radio: impl Peripheral
+ 'd,
+ _irq: impl interrupt::typelevel::Binding> + 'd,
+ ) -> Self {
+ into_ref!(radio);
+
+ let r = T::regs();
+
+ r.pcnf1.write(|w| unsafe {
+ // It is 0 bytes long in a standard BLE packet
+ w.statlen()
+ .bits(0)
+ // MaxLen configures the maximum packet payload plus add-on size in
+ // number of bytes that can be transmitted or received by the RADIO. This feature can be used to ensure
+ // that the RADIO does not overwrite, or read beyond, the RAM assigned to the packet payload. This means
+ // that if the packet payload length defined by PCNF1.STATLEN and the LENGTH field in the packet specifies a
+ // packet larger than MAXLEN, the payload will be truncated at MAXLEN
+ //
+ // To simplify the implementation, It is setted as the maximum value
+ // and the length of the packet is controlled only by the LENGTH field in the packet
+ .maxlen()
+ .bits(255)
+ // Configure the length of the address field in the packet
+ // The prefix after the address fields is always appended, so is always 1 byte less than the size of the address
+ // The base address is truncated from the least significant byte if the BALEN is less than 4
+ //
+ // BLE address is always 4 bytes long
+ .balen()
+ .bits(3) // 3 bytes base address (+ 1 prefix);
+ // Configure the endianess
+ // For BLE is always little endian (LSB first)
+ .endian()
+ .little()
+ // Data whitening is used to avoid long sequences of zeros or
+ // ones, e.g., 0b0000000 or 0b1111111, in the data bit stream.
+ // The whitener and de-whitener are defined the same way,
+ // using a 7-bit linear feedback shift register with the
+ // polynomial x7 + x4 + 1.
+ //
+ // In BLE Whitening shall be applied on the PDU and CRC of all
+ // Link Layer packets and is performed after the CRC generation
+ // in the transmitter. No other parts of the packets are whitened.
+ // De-whitening is performed before the CRC checking in the receiver
+ // Before whitening or de-whitening, the shift register should be
+ // initialized based on the channel index.
+ .whiteen()
+ .set_bit()
+ });
+
+ // Configure CRC
+ r.crccnf.write(|w| {
+ // In BLE the CRC shall be calculated on the PDU of all Link Layer
+ // packets (even if the packet is encrypted).
+ // It skips the address field
+ w.skipaddr()
+ .skip()
+ // In BLE 24-bit CRC = 3 bytes
+ .len()
+ .three()
+ });
+
+ // Ch map between 2400 MHZ .. 2500 MHz
+ // All modes use this range
+ r.frequency.write(|w| w.map().default());
+
+ // Configure shortcuts to simplify and speed up sending and receiving packets.
+ r.shorts.write(|w| {
+ // start transmission/recv immediately after ramp-up
+ // disable radio when transmission/recv is done
+ w.ready_start().enabled().end_disable().enabled()
+ });
+
+ // Enable NVIC interrupt
+ T::Interrupt::unpend();
+ unsafe { T::Interrupt::enable() };
+
+ Self { _p: radio }
+ }
+
+ fn state(&self) -> RadioState {
+ match T::regs().state.read().state().variant() {
+ Some(s) => s,
+ None => unreachable!(),
+ }
+ }
+
+ #[allow(dead_code)]
+ fn trace_state(&self) {
+ match self.state() {
+ RadioState::DISABLED => trace!("radio:state:DISABLED"),
+ RadioState::RX_RU => trace!("radio:state:RX_RU"),
+ RadioState::RX_IDLE => trace!("radio:state:RX_IDLE"),
+ RadioState::RX => trace!("radio:state:RX"),
+ RadioState::RX_DISABLE => trace!("radio:state:RX_DISABLE"),
+ RadioState::TX_RU => trace!("radio:state:TX_RU"),
+ RadioState::TX_IDLE => trace!("radio:state:TX_IDLE"),
+ RadioState::TX => trace!("radio:state:TX"),
+ RadioState::TX_DISABLE => trace!("radio:state:TX_DISABLE"),
+ }
+ }
+
+ /// Set the radio mode
+ ///
+ /// The radio must be disabled before calling this function
+ pub fn set_mode(&mut self, mode: Mode) {
+ assert!(self.state() == RadioState::DISABLED);
+
+ let r = T::regs();
+ r.mode.write(|w| w.mode().variant(mode));
+
+ r.pcnf0.write(|w| {
+ w.plen().variant(match mode {
+ Mode::BLE_1MBIT => PreambleLength::_8BIT,
+ Mode::BLE_2MBIT => PreambleLength::_16BIT,
+ Mode::BLE_LR125KBIT | Mode::BLE_LR500KBIT => PreambleLength::LONG_RANGE,
+ _ => unimplemented!(),
+ })
+ });
+ }
+
+ /// Set the header size changing the S1's len field
+ ///
+ /// The radio must be disabled before calling this function
+ pub fn set_header_expansion(&mut self, use_s1_field: bool) {
+ assert!(self.state() == RadioState::DISABLED);
+
+ let r = T::regs();
+
+ // s1 len in bits
+ let s1len: u8 = match use_s1_field {
+ false => 0,
+ true => 8,
+ };
+
+ r.pcnf0.write(|w| unsafe {
+ w
+ // Configure S0 to 1 byte length, this will represent the Data/Adv header flags
+ .s0len()
+ .set_bit()
+ // Configure the length (in bits) field to 1 byte length, this will represent the length of the payload
+ // and also be used to know how many bytes to read/write from/to the buffer
+ .lflen()
+ .bits(8)
+ // Configure the lengh (in bits) of bits in the S1 field. It could be used to represent the CTEInfo for data packages in BLE.
+ .s1len()
+ .bits(s1len)
+ });
+ }
+
+ /// Set initial data whitening value
+ /// Data whitening is used to avoid long sequences of zeros or ones, e.g., 0b0000000 or 0b1111111, in the data bit stream
+ /// On BLE the initial value is the channel index | 0x40
+ ///
+ /// The radio must be disabled before calling this function
+ pub fn set_whitening_init(&mut self, whitening_init: u8) {
+ assert!(self.state() == RadioState::DISABLED);
+
+ let r = T::regs();
+
+ r.datawhiteiv.write(|w| unsafe { w.datawhiteiv().bits(whitening_init) });
+ }
+
+ /// Set the central frequency to be used
+ /// It should be in the range 2400..2500
+ ///
+ /// [The radio must be disabled before calling this function](https://devzone.nordicsemi.com/f/nordic-q-a/15829/radio-frequency-change)
+ pub fn set_frequency(&mut self, frequency: u32) {
+ assert!(self.state() == RadioState::DISABLED);
+ assert!((2400..=2500).contains(&frequency));
+
+ let r = T::regs();
+
+ r.frequency
+ .write(|w| unsafe { w.frequency().bits((frequency - 2400) as u8) });
+ }
+
+ /// Set the acess address
+ /// This address is always constants for advertising
+ /// And a random value generate on each connection
+ /// It is used to filter the packages
+ ///
+ /// The radio must be disabled before calling this function
+ pub fn set_access_address(&mut self, access_address: u32) {
+ assert!(self.state() == RadioState::DISABLED);
+
+ let r = T::regs();
+
+ // Configure logical address
+ // The byte ordering on air is always least significant byte first for the address
+ // So for the address 0xAA_BB_CC_DD, the address on air will be DD CC BB AA
+ // The package order is BASE, PREFIX so BASE=0xBB_CC_DD and PREFIX=0xAA
+ r.prefix0
+ .write(|w| unsafe { w.ap0().bits((access_address >> 24) as u8) });
+
+ // The base address is truncated from the least significant byte (because the BALEN is less than 4)
+ // So it shifts the address to the right
+ r.base0.write(|w| unsafe { w.bits(access_address << 8) });
+
+ // Don't match tx address
+ r.txaddress.write(|w| unsafe { w.txaddress().bits(0) });
+
+ // Match on logical address
+ // This config only filter the packets by the address,
+ // so only packages send to the previous address
+ // will finish the reception (TODO: check the explanation)
+ r.rxaddresses.write(|w| {
+ w.addr0()
+ .enabled()
+ .addr1()
+ .enabled()
+ .addr2()
+ .enabled()
+ .addr3()
+ .enabled()
+ .addr4()
+ .enabled()
+ });
+ }
+
+ /// Set the CRC polynomial
+ /// It only uses the 24 least significant bits
+ ///
+ /// The radio must be disabled before calling this function
+ pub fn set_crc_poly(&mut self, crc_poly: u32) {
+ assert!(self.state() == RadioState::DISABLED);
+
+ let r = T::regs();
+
+ r.crcpoly.write(|w| unsafe {
+ // Configure the CRC polynomial
+ // Each term in the CRC polynomial is mapped to a bit in this
+ // register which index corresponds to the term's exponent.
+ // The least significant term/bit is hard-wired internally to
+ // 1, and bit number 0 of the register content is ignored by
+ // the hardware. The following example is for an 8 bit CRC
+ // polynomial: x8 + x7 + x3 + x2 + 1 = 1 1000 1101 .
+ w.crcpoly().bits(crc_poly & 0xFFFFFF)
+ });
+ }
+
+ /// Set the CRC init value
+ /// It only uses the 24 least significant bits
+ /// The CRC initial value varies depending of the PDU type
+ ///
+ /// The radio must be disabled before calling this function
+ pub fn set_crc_init(&mut self, crc_init: u32) {
+ assert!(self.state() == RadioState::DISABLED);
+
+ let r = T::regs();
+
+ r.crcinit.write(|w| unsafe { w.crcinit().bits(crc_init & 0xFFFFFF) });
+ }
+
+ /// Set the radio tx power
+ ///
+ /// The radio must be disabled before calling this function
+ pub fn set_tx_power(&mut self, tx_power: TxPower) {
+ assert!(self.state() == RadioState::DISABLED);
+
+ let r = T::regs();
+
+ r.txpower.write(|w| w.txpower().variant(tx_power));
+ }
+
+ /// Set buffer to read/write
+ ///
+ /// This method is unsound. You should guarantee that the buffer will live
+ /// for the life time of the transmission or if the buffer will be modified.
+ /// Also if the buffer is smaller than the packet length, the radio will
+ /// read/write memory out of the buffer bounds.
+ fn set_buffer(&mut self, buffer: &[u8]) -> Result<(), Error> {
+ slice_in_ram_or(buffer, Error::BufferNotInRAM)?;
+
+ let r = T::regs();
+
+ // Here it consider that the length of the packet is
+ // correctly set in the buffer, otherwise it will send
+ // unowned regions of memory
+ let ptr = buffer.as_ptr();
+
+ // Configure the payload
+ r.packetptr.write(|w| unsafe { w.bits(ptr as u32) });
+
+ Ok(())
+ }
+
+ /// Send packet
+ /// If the length byte in the package is greater than the buffer length
+ /// the radio will read memory out of the buffer bounds
+ pub async fn transmit(&mut self, buffer: &[u8]) -> Result<(), Error> {
+ self.set_buffer(buffer)?;
+
+ let r = T::regs();
+ self.trigger_and_wait_end(move || {
+ // Initialize the transmission
+ // trace!("txen");
+ r.tasks_txen.write(|w| w.tasks_txen().set_bit());
+ })
+ .await;
+
+ Ok(())
+ }
+
+ /// Receive packet
+ /// If the length byte in the received package is greater than the buffer length
+ /// the radio will write memory out of the buffer bounds
+ pub async fn receive(&mut self, buffer: &mut [u8]) -> Result<(), Error> {
+ self.set_buffer(buffer)?;
+
+ let r = T::regs();
+ self.trigger_and_wait_end(move || {
+ // Initialize the transmission
+ // trace!("rxen");
+ r.tasks_rxen.write(|w| w.tasks_rxen().set_bit());
+ })
+ .await;
+
+ Ok(())
+ }
+
+ async fn trigger_and_wait_end(&mut self, trigger: impl FnOnce()) {
+ //self.trace_state();
+
+ let r = T::regs();
+ let s = T::state();
+
+ // If the Future is dropped before the end of the transmission
+ // it disable the interrupt and stop the transmission
+ // to keep the state consistent
+ let drop = OnDrop::new(|| {
+ trace!("radio drop: stopping");
+
+ r.intenclr.write(|w| w.end().clear());
+ r.events_end.reset();
+
+ r.tasks_stop.write(|w| w.tasks_stop().set_bit());
+
+ // The docs don't explicitly mention any event to acknowledge the stop task
+ while r.events_end.read().events_end().bit_is_clear() {}
+
+ trace!("radio drop: stopped");
+ });
+
+ // trace!("radio:enable interrupt");
+ // Clear some remnant side-effects (TODO: check if this is necessary)
+ r.events_end.reset();
+
+ // Enable interrupt
+ r.intenset.write(|w| w.end().set());
+
+ compiler_fence(Ordering::SeqCst);
+
+ // Trigger the transmission
+ trigger();
+ // self.trace_state();
+
+ // On poll check if interrupt happen
+ poll_fn(|cx| {
+ s.end_waker.register(cx.waker());
+ if r.events_end.read().events_end().bit_is_set() {
+ // trace!("radio:end");
+ return core::task::Poll::Ready(());
+ }
+ Poll::Pending
+ })
+ .await;
+
+ compiler_fence(Ordering::SeqCst);
+ r.events_disabled.reset(); // ACK
+
+ // Everthing ends fine, so it disable the drop
+ drop.defuse();
+ }
+
+ /// Disable the radio
+ fn disable(&mut self) {
+ let r = T::regs();
+
+ compiler_fence(Ordering::SeqCst);
+ // If it is already disabled, do nothing
+ if self.state() != RadioState::DISABLED {
+ trace!("radio:disable");
+ // Trigger the disable task
+ r.tasks_disable.write(|w| w.tasks_disable().set_bit());
+
+ // Wait until the radio is disabled
+ while r.events_disabled.read().events_disabled().bit_is_clear() {}
+
+ compiler_fence(Ordering::SeqCst);
+
+ // Acknowledge it
+ r.events_disabled.reset();
+ }
+ }
+}
+
+impl<'d, T: Instance> Drop for Radio<'d, T> {
+ fn drop(&mut self) {
+ self.disable();
+ }
+}
diff --git a/embassy-nrf/src/radio/mod.rs b/embassy-nrf/src/radio/mod.rs
new file mode 100644
index 000000000..03f967f87
--- /dev/null
+++ b/embassy-nrf/src/radio/mod.rs
@@ -0,0 +1,75 @@
+//! Integrated 2.4 GHz Radio
+//!
+//! The 2.4 GHz radio transceiver is compatible with multiple radio standards
+//! such as 1Mbps, 2Mbps and Long Range Bluetooth Low Energy.
+
+#![macro_use]
+
+/// Bluetooth Low Energy Radio driver.
+pub mod ble;
+
+use core::marker::PhantomData;
+
+use crate::{interrupt, pac, Peripheral};
+
+/// Interrupt handler
+pub struct InterruptHandler {
+ _phantom: PhantomData,
+}
+
+impl interrupt::typelevel::Handler for InterruptHandler {
+ unsafe fn on_interrupt() {
+ let r = T::regs();
+ let s = T::state();
+
+ if r.events_end.read().events_end().bit_is_set() {
+ s.end_waker.wake();
+ r.intenclr.write(|w| w.end().clear());
+ }
+ }
+}
+
+pub(crate) mod sealed {
+ use embassy_sync::waitqueue::AtomicWaker;
+
+ pub struct State {
+ /// end packet transmission or reception
+ pub end_waker: AtomicWaker,
+ }
+ impl State {
+ pub const fn new() -> Self {
+ Self {
+ end_waker: AtomicWaker::new(),
+ }
+ }
+ }
+
+ pub trait Instance {
+ fn regs() -> &'static crate::pac::radio::RegisterBlock;
+ fn state() -> &'static State;
+ }
+}
+
+macro_rules! impl_radio {
+ ($type:ident, $pac_type:ident, $irq:ident) => {
+ impl crate::radio::sealed::Instance for peripherals::$type {
+ fn regs() -> &'static pac::radio::RegisterBlock {
+ unsafe { &*pac::$pac_type::ptr() }
+ }
+
+ fn state() -> &'static crate::radio::sealed::State {
+ static STATE: crate::radio::sealed::State = crate::radio::sealed::State::new();
+ &STATE
+ }
+ }
+ impl crate::radio::Instance for peripherals::$type {
+ type Interrupt = crate::interrupt::typelevel::$irq;
+ }
+ };
+}
+
+/// Radio peripheral instance.
+pub trait Instance: Peripheral + sealed::Instance + 'static + Send {
+ /// Interrupt for this peripheral.
+ type Interrupt: interrupt::typelevel::Interrupt;
+}