Merge commit '82f528927b2fde275c2e9b6fd737baf439cb296a'

80 files changed, 251 insertions, 99 deletions

diff --git a/ci.sh b/ci.sh
index 47bf5d660..1b3fac8bc 100755
--- a/ci.sh
+++ b/ci.sh
@@ -117,12 +117,14 @@ cargo batch  \
     --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv7em-none-eabi --features stm32f429zi --out-dir out/tests/nucleo-stm32f429zi \
     --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv7em-none-eabi --features stm32g491re --out-dir out/tests/nucleo-stm32g491re \
     --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv6m-none-eabi --features stm32g071rb --out-dir out/tests/nucleo-stm32g071rb \
+    --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv6m-none-eabi --features stm32c031c6 --out-dir out/tests/nucleo-stm32c031c6 \
     --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv7em-none-eabi --features stm32h755zi --out-dir out/tests/nucleo-stm32h755zi \
     --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv7em-none-eabi --features stm32wb55rg --out-dir out/tests/nucleo-stm32wb55rg \
     --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv7em-none-eabi --features stm32h563zi --out-dir out/tests/nucleo-stm32h563zi \
     --- build --release --manifest-path tests/stm32/Cargo.toml --target thumbv7em-none-eabi --features stm32u585ai --out-dir out/tests/iot-stm32u585ai \
     --- build --release --manifest-path tests/rp/Cargo.toml --target thumbv6m-none-eabi --out-dir out/tests/rpi-pico \
     --- build --release --manifest-path tests/nrf/Cargo.toml --target thumbv7em-none-eabi --out-dir out/tests/nrf52840-dk \
+    --- build --release --manifest-path tests/riscv32/Cargo.toml --target riscv32imac-unknown-none-elf \
     $BUILD_EXTRA
 
 
diff --git a/embassy-boot/boot/Cargo.toml b/embassy-boot/boot/Cargo.toml
index 39f501570..956b0f987 100644
--- a/embassy-boot/boot/Cargo.toml
+++ b/embassy-boot/boot/Cargo.toml
@@ -27,7 +27,7 @@ defmt = { version = "0.3", optional = true }
 digest = "0.10"
 log = { version = "0.4", optional = true  }
 ed25519-dalek = { version = "1.0.1", default_features = false, features = ["u32_backend"], optional = true }
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync" }
 embedded-storage = "0.3.0"
 embedded-storage-async = { version = "0.4.0", optional = true}
 salty = { git = "https://github.com/ycrypto/salty.git", rev = "a9f17911a5024698406b75c0fac56ab5ccf6a8c7", optional = true }
diff --git a/embassy-cortex-m/Cargo.toml b/embassy-cortex-m/Cargo.toml
index 5c5718d50..c2c4759dc 100644
--- a/embassy-cortex-m/Cargo.toml
+++ b/embassy-cortex-m/Cargo.toml
@@ -36,7 +36,7 @@ prio-bits-8 = []
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-executor = { version = "0.1.0", path = "../embassy-executor"}
 embassy-macros = { version = "0.1.0", path = "../embassy-macros"}
 embassy-hal-common = { version = "0.1.0", path = "../embassy-hal-common"}
diff --git a/embassy-embedded-hal/Cargo.toml b/embassy-embedded-hal/Cargo.toml
index c509d6ee5..19d512585 100644
--- a/embassy-embedded-hal/Cargo.toml
+++ b/embassy-embedded-hal/Cargo.toml
@@ -17,7 +17,7 @@ std = []
 nightly = ["embedded-hal-async", "embedded-storage-async"]
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embedded-hal-02 = { package = "embedded-hal", version = "0.2.6", features = ["unproven"] }
 embedded-hal-1 = { package = "embedded-hal", version = "=1.0.0-alpha.10" }
 embedded-hal-async = { version = "=0.2.0-alpha.1", optional = true }
diff --git a/embassy-executor/src/arch/riscv32.rs b/embassy-executor/src/arch/riscv32.rs
index f66daeae4..ff7ec1575 100644
--- a/embassy-executor/src/arch/riscv32.rs
+++ b/embassy-executor/src/arch/riscv32.rs
@@ -8,6 +8,9 @@ mod thread {
     use core::marker::PhantomData;
     use core::sync::atomic::{AtomicBool, Ordering};
 
+    #[cfg(feature = "nightly")]
+    pub use embassy_macros::main_riscv as main;
+
     use crate::raw::{Pender, PenderInner};
     use crate::{raw, Spawner};
 
diff --git a/embassy-hal-common/src/macros.rs b/embassy-hal-common/src/macros.rs
index da7913136..5e62e048a 100644
--- a/embassy-hal-common/src/macros.rs
+++ b/embassy-hal-common/src/macros.rs
@@ -92,7 +92,7 @@ macro_rules! impl_peripheral {
             type P = $type;
 
             #[inline]
-            unsafe fn clone_unchecked(&mut self) -> Self::P {
+            unsafe fn clone_unchecked(&self) -> Self::P {
                 $type { ..*self }
             }
         }
diff --git a/embassy-hal-common/src/peripheral.rs b/embassy-hal-common/src/peripheral.rs
index 4a6b6a600..c7133bac6 100644
--- a/embassy-hal-common/src/peripheral.rs
+++ b/embassy-hal-common/src/peripheral.rs
@@ -39,7 +39,7 @@ impl<'a, T> PeripheralRef<'a, T> {
     /// You should strongly prefer using `reborrow()` instead. It returns a
     /// `PeripheralRef` that borrows `self`, which allows the borrow checker
     /// to enforce this at compile time.
-    pub unsafe fn clone_unchecked(&mut self) -> PeripheralRef<'a, T>
+    pub unsafe fn clone_unchecked(&self) -> PeripheralRef<'a, T>
     where
         T: Peripheral<P = T>,
     {
@@ -146,14 +146,14 @@ pub trait Peripheral: Sized {
     ///
     /// You should strongly prefer using `into_ref()` instead. It returns a
     /// `PeripheralRef`, which allows the borrow checker to enforce this at compile time.
-    unsafe fn clone_unchecked(&mut self) -> Self::P;
+    unsafe fn clone_unchecked(&self) -> Self::P;
 
     /// Convert a value into a `PeripheralRef`.
     ///
     /// When called on an owned `T`, yields a `PeripheralRef<'static, T>`.
     /// When called on an `&'a mut T`, yields a `PeripheralRef<'a, T>`.
     #[inline]
-    fn into_ref<'a>(mut self) -> PeripheralRef<'a, Self::P>
+    fn into_ref<'a>(self) -> PeripheralRef<'a, Self::P>
     where
         Self: 'a,
     {
@@ -161,14 +161,14 @@ pub trait Peripheral: Sized {
     }
 }
 
-impl<'b, T: DerefMut> Peripheral for T
+impl<'b, T: Deref> Peripheral for T
 where
     T::Target: Peripheral,
 {
     type P = <T::Target as Peripheral>::P;
 
     #[inline]
-    unsafe fn clone_unchecked(&mut self) -> Self::P {
-        self.deref_mut().clone_unchecked()
+    unsafe fn clone_unchecked(&self) -> Self::P {
+        self.deref().clone_unchecked()
     }
 }
diff --git a/embassy-lora/Cargo.toml b/embassy-lora/Cargo.toml
index 604358c5b..79d5660f4 100644
--- a/embassy-lora/Cargo.toml
+++ b/embassy-lora/Cargo.toml
@@ -29,7 +29,7 @@ defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 
 embassy-time = { version = "0.1.0", path = "../embassy-time" }
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-stm32 = { version = "0.1.0", path = "../embassy-stm32", default-features = false, optional = true }
 embedded-hal-1 = { package = "embedded-hal", version = "=1.0.0-alpha.10" }
 embedded-hal-async = { version = "=0.2.0-alpha.1" }
diff --git a/embassy-net-driver-channel/Cargo.toml b/embassy-net-driver-channel/Cargo.toml
index 6cb6c3568..e475551e1 100644
--- a/embassy-net-driver-channel/Cargo.toml
+++ b/embassy-net-driver-channel/Cargo.toml
@@ -13,6 +13,6 @@ target = "thumbv7em-none-eabi"
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 embassy-net-driver = { version = "0.1.0", path = "../embassy-net-driver" }
diff --git a/embassy-net/Cargo.toml b/embassy-net/Cargo.toml
index 1854d2043..fe9514e46 100644
--- a/embassy-net/Cargo.toml
+++ b/embassy-net/Cargo.toml
@@ -43,7 +43,7 @@ smoltcp = { version = "0.9.0", default-features = false, features = [
 embassy-net-driver = { version = "0.1.0", path = "../embassy-net-driver" }
 embassy-hal-common = { version = "0.1.0", path = "../embassy-hal-common" }
 embassy-time = { version = "0.1.0", path = "../embassy-time" }
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embedded-io = { version = "0.4.0", optional = true }
 
 managed = { version = "0.8.0", default-features = false, features = [ "map" ] }
diff --git a/embassy-nrf/Cargo.toml b/embassy-nrf/Cargo.toml
index 4a4e7c9f9..e5e799d0a 100644
--- a/embassy-nrf/Cargo.toml
+++ b/embassy-nrf/Cargo.toml
@@ -80,7 +80,7 @@ _gpio-p1 = []
 [dependencies]
 embassy-executor = { version = "0.1.0", path = "../embassy-executor", optional = true }
 embassy-time = { version = "0.1.0", path = "../embassy-time", optional = true }
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-cortex-m = { version = "0.1.0", path = "../embassy-cortex-m", features = ["prio-bits-3"]}
 embassy-hal-common = {version = "0.1.0", path = "../embassy-hal-common" }
 embassy-embedded-hal = {version = "0.1.0", path = "../embassy-embedded-hal" }
diff --git a/embassy-nrf/src/buffered_uarte.rs b/embassy-nrf/src/buffered_uarte.rs
index 75f93f904..c41d8398c 100644
--- a/embassy-nrf/src/buffered_uarte.rs
+++ b/embassy-nrf/src/buffered_uarte.rs
@@ -342,7 +342,7 @@ impl<'d, U: UarteInstance, T: TimerInstance> BufferedUarte<'d, U, T> {
         r.enable.write(|w| w.enable().enabled());
 
         // Configure byte counter.
-        let mut timer = Timer::new_counter(timer);
+        let timer = Timer::new_counter(timer);
         timer.cc(1).write(rx_buffer.len() as u32 * 2);
         timer.cc(1).short_compare_clear();
         timer.clear();
diff --git a/embassy-nrf/src/saadc.rs b/embassy-nrf/src/saadc.rs
index af952f03d..8aff7df16 100644
--- a/embassy-nrf/src/saadc.rs
+++ b/embassy-nrf/src/saadc.rs
@@ -315,7 +315,7 @@ impl<'d, const N: usize> Saadc<'d, N> {
             Ppi::new_one_to_one(ppi_ch1, Event::from_reg(&r.events_end), Task::from_reg(&r.tasks_start));
         start_ppi.enable();
 
-        let mut timer = Timer::new(timer);
+        let timer = Timer::new(timer);
         timer.set_frequency(frequency);
         timer.cc(0).write(sample_counter);
         timer.cc(0).short_compare_clear();
diff --git a/embassy-nrf/src/timer.rs b/embassy-nrf/src/timer.rs
index a9487a9fd..e9d2132c1 100644
--- a/embassy-nrf/src/timer.rs
+++ b/embassy-nrf/src/timer.rs
@@ -117,7 +117,7 @@ impl<'d, T: Instance> Timer<'d, T> {
 
         let regs = T::regs();
 
-        let mut this = Self { _p: timer };
+        let this = Self { _p: timer };
 
         // Stop the timer before doing anything else,
         // since changing BITMODE while running can cause 'unpredictable behaviour' according to the specification.
@@ -213,13 +213,13 @@ impl<'d, T: Instance> Timer<'d, T> {
     ///
     /// # Panics
     /// Panics if `n` >= the number of CC registers this timer has (4 for a normal timer, 6 for an extended timer).
-    pub fn cc(&mut self, n: usize) -> Cc<T> {
+    pub fn cc(&self, n: usize) -> Cc<'d, T> {
         if n >= T::CCS {
             panic!("Cannot get CC register {} of timer with {} CC registers.", n, T::CCS);
         }
         Cc {
             n,
-            _p: self._p.reborrow(),
+            _p: unsafe { self._p.clone_unchecked() },
         }
     }
 }
diff --git a/embassy-nrf/src/uarte.rs b/embassy-nrf/src/uarte.rs
index 3934d1b55..e59b2332a 100644
--- a/embassy-nrf/src/uarte.rs
+++ b/embassy-nrf/src/uarte.rs
@@ -205,7 +205,7 @@ impl<'d, T: Instance> Uarte<'d, T> {
         ppi_ch1: impl Peripheral<P = impl ConfigurableChannel + 'd> + 'd,
         ppi_ch2: impl Peripheral<P = impl ConfigurableChannel + 'd> + 'd,
     ) -> (UarteTx<'d, T>, UarteRxWithIdle<'d, T, U>) {
-        let mut timer = Timer::new(timer);
+        let timer = Timer::new(timer);
 
         into_ref!(ppi_ch1, ppi_ch2);
 
diff --git a/embassy-nrf/src/usb/mod.rs b/embassy-nrf/src/usb/mod.rs
index 56de511df..c1f3f48cb 100644
--- a/embassy-nrf/src/usb/mod.rs
+++ b/embassy-nrf/src/usb/mod.rs
@@ -153,7 +153,7 @@ impl<'d, T: Instance, V: VbusDetect + 'd> driver::Driver<'d> for Driver<'d, T, V
         }))
     }
 
-    fn start(mut self, control_max_packet_size: u16) -> (Self::Bus, Self::ControlPipe) {
+    fn start(self, control_max_packet_size: u16) -> (Self::Bus, Self::ControlPipe) {
         (
             Bus {
                 _p: unsafe { self._p.clone_unchecked() },
diff --git a/embassy-rp/Cargo.toml b/embassy-rp/Cargo.toml
index cb9c7be77..2ef2c8f07 100644
--- a/embassy-rp/Cargo.toml
+++ b/embassy-rp/Cargo.toml
@@ -39,7 +39,7 @@ nightly = ["embassy-executor/nightly", "embedded-hal-1", "embedded-hal-async", "
 unstable-traits = ["embedded-hal-1", "embedded-hal-nb"]
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-executor = { version = "0.1.0", path = "../embassy-executor" }
 embassy-time = { version = "0.1.0", path = "../embassy-time", features = [ "tick-hz-1_000_000" ] }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
diff --git a/embassy-stm32/Cargo.toml b/embassy-stm32/Cargo.toml
index a8ebacd25..969dc3b70 100644
--- a/embassy-stm32/Cargo.toml
+++ b/embassy-stm32/Cargo.toml
@@ -31,7 +31,7 @@ flavors = [
 ]
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-executor = { version = "0.1.0", path = "../embassy-executor" }
 embassy-time = { version = "0.1.0", path = "../embassy-time", optional = true }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
@@ -58,7 +58,7 @@ sdio-host = "0.5.0"
 embedded-sdmmc = { git = "https://github.com/embassy-rs/embedded-sdmmc-rs", rev = "46d1b1c2ff13e31e282ec1e352421721694f126a", optional = true }
 critical-section = "1.1"
 atomic-polyfill = "1.0.1"
-stm32-metapac = "5"
+stm32-metapac = "6"
 vcell = "0.1.3"
 bxcan = "0.7.0"
 nb = "1.0.0"
@@ -73,7 +73,7 @@ critical-section = { version = "1.1", features = ["std"] }
 [build-dependencies]
 proc-macro2 = "1.0.36"
 quote = "1.0.15"
-stm32-metapac = { version = "5", default-features = false, features = ["metadata"]}
+stm32-metapac = { version = "6", default-features = false, features = ["metadata"]}
 
 [features]
 default = ["stm32-metapac/rt"]
diff --git a/embassy-stm32/build.rs b/embassy-stm32/build.rs
index b01e8ba45..73bd29fcf 100644
--- a/embassy-stm32/build.rs
+++ b/embassy-stm32/build.rs
@@ -180,7 +180,7 @@ fn main() {
 
         #[cfg(flash)]
         impl<'d> FlashLayout<'d> {
-            pub(crate) fn new(mut p: embassy_hal_common::PeripheralRef<'d, crate::peripherals::FLASH>) -> Self {
+            pub(crate) fn new(p: embassy_hal_common::PeripheralRef<'d, crate::peripherals::FLASH>) -> Self {
                 Self {
                     #(#inits),*
                 }
diff --git a/embassy-stm32/src/flash/common.rs b/embassy-stm32/src/flash/common.rs
index 8235d6f08..1189e447e 100644
--- a/embassy-stm32/src/flash/common.rs
+++ b/embassy-stm32/src/flash/common.rs
@@ -33,8 +33,7 @@ impl<'d> Flash<'d> {
     }
 
     pub(crate) fn release(self) -> PeripheralRef<'d, crate::peripherals::FLASH> {
-        let mut flash = self;
-        unsafe { flash.inner.clone_unchecked() }
+        unsafe { self.inner.clone_unchecked() }
     }
 }
 
diff --git a/embassy-stm32/src/flash/f4.rs b/embassy-stm32/src/flash/f4.rs
index 2ce9df69f..60ac62c17 100644
--- a/embassy-stm32/src/flash/f4.rs
+++ b/embassy-stm32/src/flash/f4.rs
@@ -67,7 +67,7 @@ mod alt_regions {
 
             // SAFETY: We never expose the cloned peripheral references, and their instance is not public.
             // Also, all flash region operations are protected with a cs.
-            let mut p = self.release();
+            let p = self.release();
             AltFlashLayout {
                 bank1_region1: Bank1Region1(&BANK1_REGION1, unsafe { p.clone_unchecked() }),
                 bank1_region2: Bank1Region2(&BANK1_REGION2, unsafe { p.clone_unchecked() }),
diff --git a/embassy-stm32/src/gpio.rs b/embassy-stm32/src/gpio.rs
index 3024f1ffa..4895684e0 100644
--- a/embassy-stm32/src/gpio.rs
+++ b/embassy-stm32/src/gpio.rs
@@ -29,7 +29,7 @@ impl<'d, T: Pin> Flex<'d, T> {
     }
 
     #[inline]
-    pub fn degrade(mut self) -> Flex<'d, AnyPin> {
+    pub fn degrade(self) -> Flex<'d, AnyPin> {
         // Safety: We are about to drop the other copy of this pin, so
         // this clone is safe.
         let pin = unsafe { self.pin.clone_unchecked() };
diff --git a/embassy-stm32/src/rcc/f2.rs b/embassy-stm32/src/rcc/f2.rs
index d543888c1..bcae64d0f 100644
--- a/embassy-stm32/src/rcc/f2.rs
+++ b/embassy-stm32/src/rcc/f2.rs
@@ -148,7 +148,7 @@ impl Into<Pllp> for PLLMainDiv {
         match self {
             PLLMainDiv::Div2 => Pllp::DIV2,
             PLLMainDiv::Div4 => Pllp::DIV4,
-            PLLMainDiv::Div6 => Pllp::DIV8,
+            PLLMainDiv::Div6 => Pllp::DIV6,
             PLLMainDiv::Div8 => Pllp::DIV8,
         }
     }
diff --git a/embassy-stm32/src/time.rs b/embassy-stm32/src/time.rs
index f08abe331..604503e61 100644
--- a/embassy-stm32/src/time.rs
+++ b/embassy-stm32/src/time.rs
@@ -8,31 +8,31 @@ use core::ops::{Div, Mul};
 pub struct Hertz(pub u32);
 
 impl Hertz {
-    pub fn hz(hertz: u32) -> Self {
+    pub const fn hz(hertz: u32) -> Self {
         Self(hertz)
     }
 
-    pub fn khz(kilohertz: u32) -> Self {
+    pub const fn khz(kilohertz: u32) -> Self {
         Self(kilohertz * 1_000)
     }
 
-    pub fn mhz(megahertz: u32) -> Self {
+    pub const fn mhz(megahertz: u32) -> Self {
         Self(megahertz * 1_000_000)
     }
 }
 
 /// This is a convenience shortcut for [`Hertz::hz`]
-pub fn hz(hertz: u32) -> Hertz {
+pub const fn hz(hertz: u32) -> Hertz {
     Hertz::hz(hertz)
 }
 
 /// This is a convenience shortcut for [`Hertz::khz`]
-pub fn khz(kilohertz: u32) -> Hertz {
+pub const fn khz(kilohertz: u32) -> Hertz {
     Hertz::khz(kilohertz)
 }
 
 /// This is a convenience shortcut for [`Hertz::mhz`]
-pub fn mhz(megahertz: u32) -> Hertz {
+pub const fn mhz(megahertz: u32) -> Hertz {
     Hertz::mhz(megahertz)
 }
 
diff --git a/embassy-sync/CHANGELOG.md b/embassy-sync/CHANGELOG.md
new file mode 100644
index 000000000..a60f3f7c4
--- /dev/null
+++ b/embassy-sync/CHANGELOG.md
@@ -0,0 +1,22 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## 0.2.0 - 2023-04-13
+
+- pubsub: Fix messages not getting popped when the last subscriber that needed them gets dropped.
+- pubsub: Move instead of clone messages when the last subscriber pops them.
+- pubsub: Pop messages which count is 0 after unsubscribe.
+- Update `embedded-io` from `0.3` to `0.4` (uses `async fn` in traits).
+- impl `Default` for `WakerRegistration`
+- impl `Default` for `Signal`
+- Remove unnecessary uses of `atomic-polyfill`
+- Add `#[must_use]` to all futures.
+
+
+## 0.1.0 - 2022-08-26
+
+- First release
\ No newline at end of file
diff --git a/embassy-sync/Cargo.toml b/embassy-sync/Cargo.toml
index e4871e718..bc06b92cd 100644
--- a/embassy-sync/Cargo.toml
+++ b/embassy-sync/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "embassy-sync"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2021"
 description = "no-std, no-alloc synchronization primitives with async support"
 repository = "https://github.com/embassy-rs/embassy"
diff --git a/embassy-time/CHANGELOG.md b/embassy-time/CHANGELOG.md
new file mode 100644
index 000000000..f4a7860e6
--- /dev/null
+++ b/embassy-time/CHANGELOG.md
@@ -0,0 +1,24 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## 0.1.1 - 2023-04-13
+
+- Update `embedded-hal-async` to `0.2.0-alpha.1` (uses `async fn` in traits).
+- Update `embedded-hal v1` to `1.0.0-alpha.10`. (Note: v0.2 support is kept unchanged).
+- Remove dep on `embassy-sync`.
+- Fix reentrancy issues in the `std` time driver (#1177)
+- Add `Duration::from_hz()`.
+- impl `From` conversions to/from `core::time::Duration`.
+- Add `#[must_use]` to all futures.
+- Add inherent `async fn tick()` to `Ticker`, so you can use it directly without the `Stream` trait.
+- Add more tick rates.
+- impl `Default` for `Signal`
+- Remove unnecessary uses of `atomic-polyfill`
+
+## 0.1.0 - 2022-08-26
+
+- First release
\ No newline at end of file
diff --git a/embassy-time/Cargo.toml b/embassy-time/Cargo.toml
index 38d31f1c4..c4edbd38a 100644
--- a/embassy-time/Cargo.toml
+++ b/embassy-time/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "embassy-time"
-version = "0.1.0"
+version = "0.1.1"
 edition = "2021"
 description = "Instant and Duration for embedded no-std systems, with async timer support"
 repository = "https://github.com/embassy-rs/embassy"
@@ -156,7 +156,6 @@ embedded-hal-1 = { package = "embedded-hal", version = "=1.0.0-alpha.10", option
 embedded-hal-async = { version = "=0.2.0-alpha.1", optional = true}
 
 futures-util = { version = "0.3.17", default-features = false }
-embassy-sync = { version = "0.1", path = "../embassy-sync" }
 atomic-polyfill = "1.0.1"
 critical-section = "1.1"
 cfg-if = "1.0.0"
diff --git a/embassy-time/src/driver_std.rs b/embassy-time/src/driver_std.rs
index da46a599d..9f8c57b5c 100644
--- a/embassy-time/src/driver_std.rs
+++ b/embassy-time/src/driver_std.rs
@@ -5,8 +5,7 @@ use std::time::{Duration as StdDuration, Instant as StdInstant};
 use std::{mem, ptr, thread};
 
 use atomic_polyfill::{AtomicU8, Ordering};
-use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
-use embassy_sync::blocking_mutex::Mutex as EmbassyMutex;
+use critical_section::Mutex as CsMutex;
 
 use crate::driver::{AlarmHandle, Driver};
 
@@ -40,7 +39,7 @@ struct TimeDriver {
     // The STD Driver implementation requires the alarms' mutex to be reentrant, which the STD Mutex isn't
     // Fortunately, mutexes based on the `critical-section` crate are reentrant, because the critical sections
     // themselves are reentrant
-    alarms: UninitCell<EmbassyMutex<CriticalSectionRawMutex, RefCell<[AlarmState; ALARM_COUNT]>>>,
+    alarms: UninitCell<CsMutex<RefCell<[AlarmState; ALARM_COUNT]>>>,
     zero_instant: UninitCell<StdInstant>,
     signaler: UninitCell<Signaler>,
 }
@@ -58,8 +57,7 @@ crate::time_driver_impl!(static DRIVER: TimeDriver = TimeDriver {
 impl TimeDriver {
     fn init(&self) {
         self.once.call_once(|| unsafe {
-            self.alarms
-                .write(EmbassyMutex::new(RefCell::new([ALARM_NEW; ALARM_COUNT])));
+            self.alarms.write(CsMutex::new(RefCell::new([ALARM_NEW; ALARM_COUNT])));
             self.zero_instant.write(StdInstant::now());
             self.signaler.write(Signaler::new());
 
@@ -72,7 +70,8 @@ impl TimeDriver {
         loop {
             let now = DRIVER.now();
 
-            let next_alarm = unsafe { DRIVER.alarms.as_ref() }.lock(|alarms| {
+            let next_alarm = critical_section::with(|cs| {
+                let alarms = unsafe { DRIVER.alarms.as_ref() }.borrow(cs);
                 loop {
                     let pending = alarms
                         .borrow_mut()
@@ -139,8 +138,8 @@ impl Driver for TimeDriver {
 
     fn set_alarm_callback(&self, alarm: AlarmHandle, callback: fn(*mut ()), ctx: *mut ()) {
         self.init();
-        unsafe { self.alarms.as_ref() }.lock(|alarms| {
-            let mut alarms = alarms.borrow_mut();
+        critical_section::with(|cs| {
+            let mut alarms = unsafe { self.alarms.as_ref() }.borrow_ref_mut(cs);
             let alarm = &mut alarms[alarm.id() as usize];
             alarm.callback = callback as *const ();
             alarm.ctx = ctx;
@@ -149,9 +148,8 @@ impl Driver for TimeDriver {
 
     fn set_alarm(&self, alarm: AlarmHandle, timestamp: u64) -> bool {
         self.init();
-        unsafe { self.alarms.as_ref() }.lock(|alarms| {
-            let mut alarms = alarms.borrow_mut();
-
+        critical_section::with(|cs| {
+            let mut alarms = unsafe { self.alarms.as_ref() }.borrow_ref_mut(cs);
             let alarm = &mut alarms[alarm.id() as usize];
             alarm.timestamp = timestamp;
             unsafe { self.signaler.as_ref() }.signal();
diff --git a/embassy-time/src/queue_generic.rs b/embassy-time/src/queue_generic.rs
index 20ae7e6cc..0f67d9dbb 100644
--- a/embassy-time/src/queue_generic.rs
+++ b/embassy-time/src/queue_generic.rs
@@ -2,8 +2,7 @@ use core::cell::RefCell;
 use core::cmp::{min, Ordering};
 use core::task::Waker;
 
-use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
-use embassy_sync::blocking_mutex::Mutex;
+use critical_section::Mutex;
 use heapless::Vec;
 
 use crate::driver::{allocate_alarm, set_alarm, set_alarm_callback, AlarmHandle};
@@ -129,7 +128,7 @@ impl InnerQueue {
 }
 
 struct Queue {
-    inner: Mutex<CriticalSectionRawMutex, RefCell<Option<InnerQueue>>>,
+    inner: Mutex<RefCell<Option<InnerQueue>>>,
 }
 
 impl Queue {
@@ -140,8 +139,8 @@ impl Queue {
     }
 
     fn schedule_wake(&'static self, at: Instant, waker: &Waker) {
-        self.inner.lock(|inner| {
-            let mut inner = inner.borrow_mut();
+        critical_section::with(|cs| {
+            let mut inner = self.inner.borrow_ref_mut(cs);
 
             if inner.is_none() {}
 
@@ -159,8 +158,7 @@ impl Queue {
     }
 
     fn handle_alarm(&self) {
-        self.inner
-            .lock(|inner| inner.borrow_mut().as_mut().unwrap().handle_alarm());
+        critical_section::with(|cs| self.inner.borrow_ref_mut(cs).as_mut().unwrap().handle_alarm())
     }
 
     fn handle_alarm_callback(ctx: *mut ()) {
diff --git a/embassy-usb-logger/Cargo.toml b/embassy-usb-logger/Cargo.toml
index 18d70b0c5..0f91cd36d 100644
--- a/embassy-usb-logger/Cargo.toml
+++ b/embassy-usb-logger/Cargo.toml
@@ -10,7 +10,7 @@ target = "thumbv7em-none-eabi"
 
 [dependencies]
 embassy-usb = { version = "0.1.0", path = "../embassy-usb" }
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 futures = { version = "0.3", default-features = false }
 static_cell = "1"
diff --git a/embassy-usb/Cargo.toml b/embassy-usb/Cargo.toml
index ae3f3ac37..03cf96a1d 100644
--- a/embassy-usb/Cargo.toml
+++ b/embassy-usb/Cargo.toml
@@ -41,7 +41,7 @@ max-handler-count-8 = []
 [dependencies]
 embassy-futures = { version = "0.1.0", path = "../embassy-futures" }
 embassy-usb-driver = { version = "0.1.0", path = "../embassy-usb-driver" }
-embassy-sync = { version = "0.1.0", path = "../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../embassy-sync" }
 embassy-net-driver-channel = { version = "0.1.0", path = "../embassy-net-driver-channel" }
 
 defmt = { version = "0.3", optional = true }
diff --git a/examples/boot/application/nrf/Cargo.toml b/examples/boot/application/nrf/Cargo.toml
index e75c73cbd..cda1917b3 100644
--- a/examples/boot/application/nrf/Cargo.toml
+++ b/examples/boot/application/nrf/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync" }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers", "arch-cortex-m", "executor-thread"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly"] }
 embassy-nrf = { version = "0.1.0", path = "../../../../embassy-nrf", features = ["time-driver-rtc1", "gpiote", "nightly"] }
diff --git a/examples/boot/application/rp/Cargo.toml b/examples/boot/application/rp/Cargo.toml
index 8de2d2ebd..9d34a3691 100644
--- a/examples/boot/application/rp/Cargo.toml
+++ b/examples/boot/application/rp/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync" }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers", "arch-cortex-m", "executor-thread"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly"] }
 embassy-rp = { version = "0.1.0", path = "../../../../embassy-rp", features = ["time-driver", "unstable-traits", "nightly"] }
diff --git a/examples/boot/application/stm32f3/Cargo.toml b/examples/boot/application/stm32f3/Cargo.toml
index 083607de5..8e978eb24 100644
--- a/examples/boot/application/stm32f3/Cargo.toml
+++ b/examples/boot/application/stm32f3/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32f303re", "time-driver-any", "exti"]  }
diff --git a/examples/boot/application/stm32f7/Cargo.toml b/examples/boot/application/stm32f7/Cargo.toml
index 74f508515..fb55b166d 100644
--- a/examples/boot/application/stm32f7/Cargo.toml
+++ b/examples/boot/application/stm32f7/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32f767zi", "time-driver-any", "exti"]  }
diff --git a/examples/boot/application/stm32h7/Cargo.toml b/examples/boot/application/stm32h7/Cargo.toml
index 898b9a47e..ea6b905a4 100644
--- a/examples/boot/application/stm32h7/Cargo.toml
+++ b/examples/boot/application/stm32h7/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync" }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32h743zi", "time-driver-any", "exti"]  }
diff --git a/examples/boot/application/stm32l0/Cargo.toml b/examples/boot/application/stm32l0/Cargo.toml
index e142c8481..6ba18564d 100644
--- a/examples/boot/application/stm32l0/Cargo.toml
+++ b/examples/boot/application/stm32l0/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32l072cz", "time-driver-any", "exti", "memory-x"]  }
diff --git a/examples/boot/application/stm32l1/Cargo.toml b/examples/boot/application/stm32l1/Cargo.toml
index f0e92e1ac..d5b8e3e01 100644
--- a/examples/boot/application/stm32l1/Cargo.toml
+++ b/examples/boot/application/stm32l1/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32l151cb-a", "time-driver-any", "exti"]  }
diff --git a/examples/boot/application/stm32l4/Cargo.toml b/examples/boot/application/stm32l4/Cargo.toml
index 87689e9a9..ccd1fe2ee 100644
--- a/examples/boot/application/stm32l4/Cargo.toml
+++ b/examples/boot/application/stm32l4/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32l475vg", "time-driver-any", "exti"]  }
diff --git a/examples/boot/application/stm32wl/Cargo.toml b/examples/boot/application/stm32wl/Cargo.toml
index a6708bf51..128afd51e 100644
--- a/examples/boot/application/stm32wl/Cargo.toml
+++ b/examples/boot/application/stm32wl/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../../../embassy-time", features = ["nightly", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../../../embassy-stm32", features = ["unstable-traits", "nightly", "stm32wl55jc-cm4", "time-driver-any", "exti"]  }
diff --git a/examples/nrf-rtos-trace/Cargo.toml b/examples/nrf-rtos-trace/Cargo.toml
index 7910b372a..6f7cb8875 100644
--- a/examples/nrf-rtos-trace/Cargo.toml
+++ b/examples/nrf-rtos-trace/Cargo.toml
@@ -16,7 +16,7 @@ log = [
 ]
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync" }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync" }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "rtos-trace", "rtos-trace-interrupt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time" }
 embassy-nrf = { version = "0.1.0", path = "../../embassy-nrf", features = ["nrf52840", "time-driver-rtc1", "gpiote", "unstable-pac"] }
diff --git a/examples/nrf52840/Cargo.toml b/examples/nrf52840/Cargo.toml
index 3ece24066..fc614cb80 100644
--- a/examples/nrf52840/Cargo.toml
+++ b/examples/nrf52840/Cargo.toml
@@ -11,7 +11,7 @@ nightly = ["embassy-executor/nightly", "embassy-nrf/nightly", "embassy-net/night
 
 [dependencies]
 embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime"] }
 embassy-nrf = { version = "0.1.0", path = "../../embassy-nrf", features = ["defmt", "nrf52840", "time-driver-rtc1", "gpiote", "unstable-pac", "time"] }
diff --git a/examples/nrf5340/Cargo.toml b/examples/nrf5340/Cargo.toml
index 4134db46f..2c3a12964 100644
--- a/examples/nrf5340/Cargo.toml
+++ b/examples/nrf5340/Cargo.toml
@@ -6,7 +6,7 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = [
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = [
     "defmt",
 ] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", 
diff --git a/examples/rp/Cargo.toml b/examples/rp/Cargo.toml
index 63d0ac82a..f0fd27991 100644
--- a/examples/rp/Cargo.toml
+++ b/examples/rp/Cargo.toml
@@ -7,7 +7,7 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 embassy-embedded-hal = { version = "0.1.0", path = "../../embassy-embedded-hal", features = ["defmt"] }
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime"] }
 embassy-rp = { version = "0.1.0", path = "../../embassy-rp", features = ["defmt", "unstable-traits", "nightly", "unstable-pac", "time-driver", "pio", "critical-section-impl"] }
diff --git a/examples/std/Cargo.toml b/examples/std/Cargo.toml
index ff08e378c..9938c693a 100644
--- a/examples/std/Cargo.toml
+++ b/examples/std/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["log"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["log"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-std", "executor-thread", "log", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["log", "std", "nightly"] }
 embassy-net = { version = "0.1.0", path = "../../embassy-net", features=[ "std", "nightly", "log", "medium-ethernet", "tcp", "udp", "dns", "dhcpv4", "unstable-traits", "proto-ipv6"] }
diff --git a/examples/stm32c0/Cargo.toml b/examples/stm32c0/Cargo.toml
index 3b1d888f6..5667200e3 100644
--- a/examples/stm32c0/Cargo.toml
+++ b/examples/stm32c0/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "time-driver-any", "stm32c031c6", "memory-x", "unstable-pac", "exti"]  }
diff --git a/examples/stm32f0/Cargo.toml b/examples/stm32f0/Cargo.toml
index 5c82c5579..2ff252622 100644
--- a/examples/stm32f0/Cargo.toml
+++ b/examples/stm32f0/Cargo.toml
@@ -12,7 +12,7 @@ cortex-m-rt = "0.7.0"
 defmt = "0.3"
 defmt-rtt = "0.4"
 panic-probe = "0.3"
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "memory-x", "stm32f091rc", "time-driver-any", "exti", "unstable-pac"] }
diff --git a/examples/stm32f1/Cargo.toml b/examples/stm32f1/Cargo.toml
index 99f37cdda..d08e00b0b 100644
--- a/examples/stm32f1/Cargo.toml
+++ b/examples/stm32f1/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32f103c8", "unstable-pac", "memory-x", "time-driver-any", "unstable-traits" ]  }
diff --git a/examples/stm32f2/Cargo.toml b/examples/stm32f2/Cargo.toml
index ffb232310..02045a79f 100644
--- a/examples/stm32f2/Cargo.toml
+++ b/examples/stm32f2/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32f207zg", "unstable-pac", "memory-x", "time-driver-any", "exti"]  }
diff --git a/examples/stm32f3/Cargo.toml b/examples/stm32f3/Cargo.toml
index 38f11201d..a62eba9ec 100644
--- a/examples/stm32f3/Cargo.toml
+++ b/examples/stm32f3/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32f303ze", "unstable-pac", "memory-x", "time-driver-any", "exti"]  }
diff --git a/examples/stm32f4/Cargo.toml b/examples/stm32f4/Cargo.toml
index d967d8501..4b2f3d21c 100644
--- a/examples/stm32f4/Cargo.toml
+++ b/examples/stm32f4/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers", "arch-cortex-m", "executor-thread", "executor-interrupt"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "unstable-traits", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "unstable-traits", "defmt", "stm32f429zi", "unstable-pac", "memory-x", "time-driver-any", "exti"]  }
diff --git a/examples/stm32f7/Cargo.toml b/examples/stm32f7/Cargo.toml
index 74e7bf53d..898e05c12 100644
--- a/examples/stm32f7/Cargo.toml
+++ b/examples/stm32f7/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32f767zi", "unstable-pac", "time-driver-any", "exti"]  }
diff --git a/examples/stm32g0/Cargo.toml b/examples/stm32g0/Cargo.toml
index 03bdbcea3..a522fb422 100644
--- a/examples/stm32g0/Cargo.toml
+++ b/examples/stm32g0/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "time-driver-any", "stm32g071rb", "memory-x", "unstable-pac", "exti"]  }
diff --git a/examples/stm32g4/Cargo.toml b/examples/stm32g4/Cargo.toml
index 4e4150350..b275eb190 100644
--- a/examples/stm32g4/Cargo.toml
+++ b/examples/stm32g4/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "time-driver-any", "stm32g491re", "memory-x", "unstable-pac", "exti"]  }
diff --git a/examples/stm32h5/Cargo.toml b/examples/stm32h5/Cargo.toml
index b77d376ca..149f8a58b 100644
--- a/examples/stm32h5/Cargo.toml
+++ b/examples/stm32h5/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "unstable-traits", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32h563zi", "time-driver-any", "exti", "unstable-pac", "unstable-traits"] }
diff --git a/examples/stm32h7/Cargo.toml b/examples/stm32h7/Cargo.toml
index 154f5a987..8316498ca 100644
--- a/examples/stm32h7/Cargo.toml
+++ b/examples/stm32h7/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "unstable-traits", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32h743bi", "time-driver-any", "exti", "unstable-pac", "unstable-traits"] }
diff --git a/examples/stm32l0/Cargo.toml b/examples/stm32l0/Cargo.toml
index 413d5c18f..d446d41b2 100644
--- a/examples/stm32l0/Cargo.toml
+++ b/examples/stm32l0/Cargo.toml
@@ -9,7 +9,7 @@ default = ["nightly"]
 nightly = ["embassy-stm32/nightly", "embassy-lora", "lorawan-device", "lorawan", "embedded-io/async"]
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["defmt", "stm32l072cz", "time-driver-any", "exti", "unstable-traits", "memory-x"]  }
diff --git a/examples/stm32l1/Cargo.toml b/examples/stm32l1/Cargo.toml
index cd9508d57..e071c5d27 100644
--- a/examples/stm32l1/Cargo.toml
+++ b/examples/stm32l1/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32l151cb-a", "time-driver-any", "memory-x"]  }
diff --git a/examples/stm32l4/Cargo.toml b/examples/stm32l4/Cargo.toml
index fa39df6db..e83f261e6 100644
--- a/examples/stm32l4/Cargo.toml
+++ b/examples/stm32l4/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-embedded-hal = { version = "0.1.0", path = "../../embassy-embedded-hal" }
diff --git a/examples/stm32l5/Cargo.toml b/examples/stm32l5/Cargo.toml
index 1c662b9da..af305a19d 100644
--- a/examples/stm32l5/Cargo.toml
+++ b/examples/stm32l5/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "unstable-pac", "stm32l552ze", "time-driver-any", "exti", "unstable-traits", "memory-x"]  }
diff --git a/examples/stm32u5/Cargo.toml b/examples/stm32u5/Cargo.toml
index ebef0a4f7..65fc1b988 100644
--- a/examples/stm32u5/Cargo.toml
+++ b/examples/stm32u5/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "unstable-pac", "stm32u585ai", "time-driver-any", "memory-x" ]  }
diff --git a/examples/stm32wb/Cargo.toml b/examples/stm32wb/Cargo.toml
index ddf9729e6..835985ec3 100644
--- a/examples/stm32wb/Cargo.toml
+++ b/examples/stm32wb/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32wb55cc", "time-driver-any", "exti"]  }
diff --git a/examples/stm32wl/Cargo.toml b/examples/stm32wl/Cargo.toml
index 0d2194ea2..df295ca49 100644
--- a/examples/stm32wl/Cargo.toml
+++ b/examples/stm32wl/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
 embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32wl55jc-cm4", "time-driver-any", "memory-x", "unstable-pac", "exti"]  }
diff --git a/examples/wasm/Cargo.toml b/examples/wasm/Cargo.toml
index 430d0b4c7..5f36eb77f 100644
--- a/examples/wasm/Cargo.toml
+++ b/examples/wasm/Cargo.toml
@@ -8,7 +8,7 @@ license = "MIT OR Apache-2.0"
 crate-type = ["cdylib"]
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["log"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["log"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-wasm", "executor-thread", "log", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["log", "wasm", "nightly"] }
 
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index 9785cd9eb..f7183d167 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,7 +1,7 @@
 # Before upgrading check that everything is available on all tier1 targets here:
 # https://rust-lang.github.io/rustup-components-history
 [toolchain]
-channel = "nightly-2023-04-02"
+channel = "nightly-2023-04-11"
 components = [ "rust-src", "rustfmt", "llvm-tools-preview" ]
 targets = [
     "thumbv7em-none-eabi",
diff --git a/tests/nrf/Cargo.toml b/tests/nrf/Cargo.toml
index 912749e5d..22435e55b 100644
--- a/tests/nrf/Cargo.toml
+++ b/tests/nrf/Cargo.toml
@@ -6,7 +6,7 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt", "nightly"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt", "nightly"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "nightly", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "nightly", "defmt-timestamp-uptime"] }
 embassy-nrf = { version = "0.1.0", path = "../../embassy-nrf", features = ["defmt", "nightly", "unstable-traits", "nrf52840", "time-driver-rtc1", "gpiote", "unstable-pac"] }
diff --git a/tests/riscv32/.cargo/config.toml b/tests/riscv32/.cargo/config.toml
new file mode 100644
index 000000000..58299b54e
--- /dev/null
+++ b/tests/riscv32/.cargo/config.toml
@@ -0,0 +1,5 @@
+[target.riscv32imac-unknown-none-elf]
+runner = "true"
+
+[build]
+target = "riscv32imac-unknown-none-elf"
diff --git a/tests/riscv32/Cargo.toml b/tests/riscv32/Cargo.toml
new file mode 100644
index 000000000..01b424de8
--- /dev/null
+++ b/tests/riscv32/Cargo.toml
@@ -0,0 +1,46 @@
+[package]
+edition = "2021"
+name = "embassy-riscv-tests"
+version = "0.1.0"
+license = "MIT OR Apache-2.0"
+
+[dependencies]
+critical-section = { version = "1.1.1", features = ["restore-state-bool"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync" }
+embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-riscv32", "nightly", "executor-thread"] }
+embassy-time = { version = "0.1.0", path = "../../embassy-time" }
+embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
+
+riscv-rt = "0.11"
+riscv = { version = "0.10", features = ["critical-section-single-hart"] }
+
+
+[profile.dev]
+debug = 2
+debug-assertions = true
+opt-level = 's'
+overflow-checks = true
+
+[profile.release]
+codegen-units = 1
+debug = 2
+debug-assertions = false
+incremental = false
+lto = "fat"
+opt-level = 's'
+overflow-checks = false
+
+# do not optimize proc-macro crates = faster builds from scratch
+[profile.dev.build-override]
+codegen-units = 8
+debug = false
+debug-assertions = false
+opt-level = 0
+overflow-checks = false
+
+[profile.release.build-override]
+codegen-units = 8
+debug = false
+debug-assertions = false
+opt-level = 0
+overflow-checks = false
diff --git a/tests/riscv32/build.rs b/tests/riscv32/build.rs
new file mode 100644
index 000000000..e4a26c4a1
--- /dev/null
+++ b/tests/riscv32/build.rs
@@ -0,0 +1,8 @@
+use std::error::Error;
+
+fn main() -> Result<(), Box<dyn Error>> {
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+    println!("cargo:rustc-link-arg-bins=-Tlink.x");
+
+    Ok(())
+}
diff --git a/tests/riscv32/memory.x b/tests/riscv32/memory.x
new file mode 100644
index 000000000..316d577d4
--- /dev/null
+++ b/tests/riscv32/memory.x
@@ -0,0 +1,14 @@
+MEMORY
+{
+  ROM : ORIGIN = 0x80000000, LENGTH = 0x00020000
+  RAM : ORIGIN = 0x84000000, LENGTH = 0x00008000
+}
+
+REGION_ALIAS("REGION_TEXT", ROM);
+REGION_ALIAS("REGION_RODATA", ROM);
+REGION_ALIAS("REGION_DATA", RAM);
+REGION_ALIAS("REGION_BSS", RAM);
+REGION_ALIAS("REGION_HEAP", RAM);
+REGION_ALIAS("REGION_STACK", RAM);
+
+_stack_start = ORIGIN(RAM) + LENGTH(RAM) - 4;
diff --git a/tests/riscv32/src/bin/empty.rs b/tests/riscv32/src/bin/empty.rs
new file mode 100644
index 000000000..1874caec4
--- /dev/null
+++ b/tests/riscv32/src/bin/empty.rs
@@ -0,0 +1,16 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use embassy_executor::Spawner;
+
+#[panic_handler]
+fn panic(_info: &core::panic::PanicInfo) -> ! {
+    loop {}
+}
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    // Don't do anything, just make sure it compiles.
+    loop {}
+}
diff --git a/tests/rp/Cargo.toml b/tests/rp/Cargo.toml
index 463a370fe..36ff735ec 100644
--- a/tests/rp/Cargo.toml
+++ b/tests/rp/Cargo.toml
@@ -5,7 +5,7 @@ version = "0.1.0"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt"] }
 embassy-rp = { version = "0.1.0", path = "../../embassy-rp", features = ["nightly", "defmt", "unstable-pac", "unstable-traits", "time-driver", "critical-section-impl"]  }
diff --git a/tests/stm32/Cargo.toml b/tests/stm32/Cargo.toml
index bd181f235..8b70a1015 100644
--- a/tests/stm32/Cargo.toml
+++ b/tests/stm32/Cargo.toml
@@ -8,6 +8,7 @@ license = "MIT OR Apache-2.0"
 stm32f103c8 = ["embassy-stm32/stm32f103c8"]     # Blue Pill
 stm32f429zi = ["embassy-stm32/stm32f429zi"]     # Nucleo
 stm32g071rb = ["embassy-stm32/stm32g071rb"]     # Nucleo
+stm32c031c6 = ["embassy-stm32/stm32c031c6"]     # Nucleo
 stm32g491re = ["embassy-stm32/stm32g491re"]     # Nucleo
 stm32h755zi = ["embassy-stm32/stm32h755zi-cm7"] # Nucleo
 stm32wb55rg = ["embassy-stm32/stm32wb55rg"]     # Nucleo
@@ -15,10 +16,10 @@ stm32h563zi = ["embassy-stm32/stm32h563zi"]     # Nucleo
 stm32u585ai = ["embassy-stm32/stm32u585ai"]     # IoT board
 
 [dependencies]
-embassy-sync = { version = "0.1.0", path = "../../embassy-sync", features = ["defmt"] }
+embassy-sync = { version = "0.2.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.0", path = "../../embassy-time", features = ["defmt", "tick-hz-32_768"] }
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "unstable-pac", "memory-x", "time-driver-tim2"]  }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "unstable-pac", "memory-x", "time-driver-any"]  }
 
 defmt = "0.3.0"
 defmt-rtt = "0.4"
diff --git a/tests/stm32/build.rs b/tests/stm32/build.rs
index 6f4872249..3e67a7392 100644
--- a/tests/stm32/build.rs
+++ b/tests/stm32/build.rs
@@ -9,7 +9,13 @@ fn main() -> Result<(), Box<dyn Error>> {
     println!("cargo:rerun-if-changed=link_ram.x");
 
     println!("cargo:rustc-link-arg-bins=--nmagic");
+
+    // too little RAM to run from RAM.
+    #[cfg(any(feature = "stm32c031c6"))]
+    println!("cargo:rustc-link-arg-bins=-Tlink.x");
+    #[cfg(not(any(feature = "stm32c031c6")))]
     println!("cargo:rustc-link-arg-bins=-Tlink_ram.x");
+
     println!("cargo:rustc-link-arg-bins=-Tdefmt.x");
 
     Ok(())
diff --git a/tests/stm32/src/bin/gpio.rs b/tests/stm32/src/bin/gpio.rs
index 6a36df8cc..8b99b08a5 100644
--- a/tests/stm32/src/bin/gpio.rs
+++ b/tests/stm32/src/bin/gpio.rs
@@ -32,6 +32,8 @@ async fn main(_spawner: Spawner) {
     let (mut a, mut b) = (p.PD9, p.PD8);
     #[cfg(feature = "stm32h563zi")]
     let (mut a, mut b) = (p.PB6, p.PB7);
+    #[cfg(feature = "stm32c031c6")]
+    let (mut a, mut b) = (p.PB6, p.PB7);
 
     // Test initial output
     {
diff --git a/tests/stm32/src/bin/spi.rs b/tests/stm32/src/bin/spi.rs
index bf8098b1b..0f5e563b1 100644
--- a/tests/stm32/src/bin/spi.rs
+++ b/tests/stm32/src/bin/spi.rs
@@ -32,6 +32,8 @@ async fn main(_spawner: Spawner) {
     let (spi, sck, mosi, miso) = (p.SPI1, p.PE13, p.PE15, p.PE14);
     #[cfg(feature = "stm32h563zi")]
     let (spi, sck, mosi, miso) = (p.SPI4, p.PE12, p.PE14, p.PE13);
+    #[cfg(feature = "stm32c031c6")]
+    let (spi, sck, mosi, miso) = (p.SPI1, p.PA5, p.PA7, p.PA6);
 
     info!("asdfa;");
     let mut spi = Spi::new(
@@ -49,7 +51,7 @@ async fn main(_spawner: Spawner) {
 
     // Arduino pins D11 and D12 (MOSI-MISO) are connected together with a 1K resistor.
     // so we should get the data we sent back.
-    let mut buf = data;
+    let mut buf = [0; 9];
     spi.blocking_transfer(&mut buf, &data).unwrap();
     assert_eq!(buf, data);
 
diff --git a/tests/stm32/src/bin/spi_dma.rs b/tests/stm32/src/bin/spi_dma.rs
index b3dad8132..74776ebf8 100644
--- a/tests/stm32/src/bin/spi_dma.rs
+++ b/tests/stm32/src/bin/spi_dma.rs
@@ -31,6 +31,8 @@ async fn main(_spawner: Spawner) {
     let (spi, sck, mosi, miso, tx_dma, rx_dma) = (p.SPI1, p.PE13, p.PE15, p.PE14, p.GPDMA1_CH0, p.GPDMA1_CH1);
     #[cfg(feature = "stm32h563zi")]
     let (spi, sck, mosi, miso, tx_dma, rx_dma) = (p.SPI4, p.PE12, p.PE14, p.PE13, p.GPDMA1_CH0, p.GPDMA1_CH1);
+    #[cfg(feature = "stm32c031c6")]
+    let (spi, sck, mosi, miso, tx_dma, rx_dma) = (p.SPI1, p.PA5, p.PA7, p.PA6, p.DMA1_CH1, p.DMA1_CH2);
 
     let mut spi = Spi::new(
         spi,
diff --git a/tests/stm32/src/bin/usart.rs b/tests/stm32/src/bin/usart.rs
index 52409567c..cca8c42ee 100644
--- a/tests/stm32/src/bin/usart.rs
+++ b/tests/stm32/src/bin/usart.rs
@@ -34,6 +34,8 @@ async fn main(_spawner: Spawner) {
     let (tx, rx, usart, irq) = (p.PD8, p.PD9, p.USART3, interrupt::take!(USART3));
     #[cfg(feature = "stm32h563zi")]
     let (tx, rx, usart, irq) = (p.PB6, p.PB7, p.LPUART1, interrupt::take!(LPUART1));
+    #[cfg(feature = "stm32c031c6")]
+    let (tx, rx, usart, irq) = (p.PB6, p.PB7, p.USART1, interrupt::take!(USART1));
 
     let config = Config::default();
     let mut usart = Uart::new(usart, rx, tx, irq, NoDma, NoDma, config);
diff --git a/tests/stm32/src/bin/usart_dma.rs b/tests/stm32/src/bin/usart_dma.rs
index 3f70791c1..d673df0f3 100644
--- a/tests/stm32/src/bin/usart_dma.rs
+++ b/tests/stm32/src/bin/usart_dma.rs
@@ -71,6 +71,9 @@ async fn main(_spawner: Spawner) {
         p.GPDMA1_CH0,
         p.GPDMA1_CH1,
     );
+    #[cfg(feature = "stm32c031c6")]
+    let (tx, rx, usart, irq, tx_dma, rx_dma) =
+        (p.PB6, p.PB7, p.USART1, interrupt::take!(USART1), p.DMA1_CH1, p.DMA1_CH2);
 
     let config = Config::default();
     let mut usart = Uart::new(usart, rx, tx, irq, tx_dma, rx_dma, config);