Initial STM32F1 family support with two examples for STM32F103C8 (Blue Pill)

.github/workflows/rust.yml

@@ -101,6 +101,8 @@ jobs:
             target: thumbv6m-none-eabi
           - package: examples/wasm
             target: wasm32-unknown-unknown
+          - package: examples/stm32f1
+            target: thumbv7m-none-eabi
     steps:
       - uses: actions/checkout@v2
         with:

embassy-stm32/Cargo.toml

@@ -28,6 +28,7 @@ stm32-metapac = { version = "0.1.0", path = "../stm32-metapac", features = ["rt"
 vcell = { version = "0.1.3", optional = true }
 bxcan = "0.5.1"
 seq-macro = "0.2.2"
+cast = { version = "0.2.2", default-features = false }
 
 cfg-if = "1.0.0"
 
@@ -134,6 +135,101 @@ stm32f091vc = [ "stm32-metapac/stm32f091vc" ]
 stm32f098cc = [ "stm32-metapac/stm32f098cc" ]
 stm32f098rc = [ "stm32-metapac/stm32f098rc" ]
 stm32f098vc = [ "stm32-metapac/stm32f098vc" ]
+stm32f100c4 = [ "stm32-metapac/stm32f100c4" ]
+stm32f100c6 = [ "stm32-metapac/stm32f100c6" ]
+stm32f100c8 = [ "stm32-metapac/stm32f100c8" ]
+stm32f100cb = [ "stm32-metapac/stm32f100cb" ]
+stm32f100r4 = [ "stm32-metapac/stm32f100r4" ]
+stm32f100r6 = [ "stm32-metapac/stm32f100r6" ]
+stm32f100r8 = [ "stm32-metapac/stm32f100r8" ]
+stm32f100rb = [ "stm32-metapac/stm32f100rb" ]
+stm32f100rc = [ "stm32-metapac/stm32f100rc" ]
+stm32f100rd = [ "stm32-metapac/stm32f100rd" ]
+stm32f100re = [ "stm32-metapac/stm32f100re" ]
+stm32f100v8 = [ "stm32-metapac/stm32f100v8" ]
+stm32f100vb = [ "stm32-metapac/stm32f100vb" ]
+stm32f100vc = [ "stm32-metapac/stm32f100vc" ]
+stm32f100vd = [ "stm32-metapac/stm32f100vd" ]
+stm32f100ve = [ "stm32-metapac/stm32f100ve" ]
+stm32f100zc = [ "stm32-metapac/stm32f100zc" ]
+stm32f100zd = [ "stm32-metapac/stm32f100zd" ]
+stm32f100ze = [ "stm32-metapac/stm32f100ze" ]
+stm32f101c4 = [ "stm32-metapac/stm32f101c4" ]
+stm32f101c6 = [ "stm32-metapac/stm32f101c6" ]
+stm32f101c8 = [ "stm32-metapac/stm32f101c8" ]
+stm32f101cb = [ "stm32-metapac/stm32f101cb" ]
+stm32f101r4 = [ "stm32-metapac/stm32f101r4" ]
+stm32f101r6 = [ "stm32-metapac/stm32f101r6" ]
+stm32f101r8 = [ "stm32-metapac/stm32f101r8" ]
+stm32f101rb = [ "stm32-metapac/stm32f101rb" ]
+stm32f101rc = [ "stm32-metapac/stm32f101rc" ]
+stm32f101rd = [ "stm32-metapac/stm32f101rd" ]
+stm32f101re = [ "stm32-metapac/stm32f101re" ]
+stm32f101rf = [ "stm32-metapac/stm32f101rf" ]
+stm32f101rg = [ "stm32-metapac/stm32f101rg" ]
+stm32f101t4 = [ "stm32-metapac/stm32f101t4" ]
+stm32f101t6 = [ "stm32-metapac/stm32f101t6" ]
+stm32f101t8 = [ "stm32-metapac/stm32f101t8" ]
+stm32f101tb = [ "stm32-metapac/stm32f101tb" ]
+stm32f101v8 = [ "stm32-metapac/stm32f101v8" ]
+stm32f101vb = [ "stm32-metapac/stm32f101vb" ]
+stm32f101vc = [ "stm32-metapac/stm32f101vc" ]
+stm32f101vd = [ "stm32-metapac/stm32f101vd" ]
+stm32f101ve = [ "stm32-metapac/stm32f101ve" ]
+stm32f101vf = [ "stm32-metapac/stm32f101vf" ]
+stm32f101vg = [ "stm32-metapac/stm32f101vg" ]
+stm32f101zc = [ "stm32-metapac/stm32f101zc" ]
+stm32f101zd = [ "stm32-metapac/stm32f101zd" ]
+stm32f101ze = [ "stm32-metapac/stm32f101ze" ]
+stm32f101zf = [ "stm32-metapac/stm32f101zf" ]
+stm32f101zg = [ "stm32-metapac/stm32f101zg" ]
+stm32f102c4 = [ "stm32-metapac/stm32f102c4" ]
+stm32f102c6 = [ "stm32-metapac/stm32f102c6" ]
+stm32f102c8 = [ "stm32-metapac/stm32f102c8" ]
+stm32f102cb = [ "stm32-metapac/stm32f102cb" ]
+stm32f102r4 = [ "stm32-metapac/stm32f102r4" ]
+stm32f102r6 = [ "stm32-metapac/stm32f102r6" ]
+stm32f102r8 = [ "stm32-metapac/stm32f102r8" ]
+stm32f102rb = [ "stm32-metapac/stm32f102rb" ]
+stm32f103c4 = [ "stm32-metapac/stm32f103c4" ]
+stm32f103c6 = [ "stm32-metapac/stm32f103c6" ]
+stm32f103c8 = [ "stm32-metapac/stm32f103c8" ]
+stm32f103cb = [ "stm32-metapac/stm32f103cb" ]
+stm32f103r4 = [ "stm32-metapac/stm32f103r4" ]
+stm32f103r6 = [ "stm32-metapac/stm32f103r6" ]
+stm32f103r8 = [ "stm32-metapac/stm32f103r8" ]
+stm32f103rb = [ "stm32-metapac/stm32f103rb" ]
+stm32f103rc = [ "stm32-metapac/stm32f103rc" ]
+stm32f103rd = [ "stm32-metapac/stm32f103rd" ]
+stm32f103re = [ "stm32-metapac/stm32f103re" ]
+stm32f103rf = [ "stm32-metapac/stm32f103rf" ]
+stm32f103rg = [ "stm32-metapac/stm32f103rg" ]
+stm32f103t4 = [ "stm32-metapac/stm32f103t4" ]
+stm32f103t6 = [ "stm32-metapac/stm32f103t6" ]
+stm32f103t8 = [ "stm32-metapac/stm32f103t8" ]
+stm32f103tb = [ "stm32-metapac/stm32f103tb" ]
+stm32f103v8 = [ "stm32-metapac/stm32f103v8" ]
+stm32f103vb = [ "stm32-metapac/stm32f103vb" ]
+stm32f103vc = [ "stm32-metapac/stm32f103vc" ]
+stm32f103vd = [ "stm32-metapac/stm32f103vd" ]
+stm32f103ve = [ "stm32-metapac/stm32f103ve" ]
+stm32f103vf = [ "stm32-metapac/stm32f103vf" ]
+stm32f103vg = [ "stm32-metapac/stm32f103vg" ]
+stm32f103zc = [ "stm32-metapac/stm32f103zc" ]
+stm32f103zd = [ "stm32-metapac/stm32f103zd" ]
+stm32f103ze = [ "stm32-metapac/stm32f103ze" ]
+stm32f103zf = [ "stm32-metapac/stm32f103zf" ]
+stm32f103zg = [ "stm32-metapac/stm32f103zg" ]
+stm32f105r8 = [ "stm32-metapac/stm32f105r8" ]
+stm32f105rb = [ "stm32-metapac/stm32f105rb" ]
+stm32f105rc = [ "stm32-metapac/stm32f105rc" ]
+stm32f105v8 = [ "stm32-metapac/stm32f105v8" ]
+stm32f105vb = [ "stm32-metapac/stm32f105vb" ]
+stm32f105vc = [ "stm32-metapac/stm32f105vc" ]
+stm32f107rb = [ "stm32-metapac/stm32f107rb" ]
+stm32f107rc = [ "stm32-metapac/stm32f107rc" ]
+stm32f107vb = [ "stm32-metapac/stm32f107vb" ]
+stm32f107vc = [ "stm32-metapac/stm32f107vc" ]
 stm32f401cb = [ "stm32-metapac/stm32f401cb" ]
 stm32f401cc = [ "stm32-metapac/stm32f401cc" ]
 stm32f401cd = [ "stm32-metapac/stm32f401cd" ]

embassy-stm32/src/exti.rs

@@ -30,7 +30,7 @@ fn cpu_regs() -> pac::exti::Exti {
     EXTI
 }
 
-#[cfg(not(any(exti_g0, exti_l5)))]
+#[cfg(not(any(exti_g0, exti_l5, gpio_v1)))]
 fn exticr_regs() -> pac::syscfg::Syscfg {
     pac::SYSCFG
 }
@@ -38,6 +38,10 @@ fn exticr_regs() -> pac::syscfg::Syscfg {
 fn exticr_regs() -> pac::exti::Exti {
     EXTI
 }
+#[cfg(gpio_v1)]
+fn exticr_regs() -> pac::afio::Afio {
+    pac::AFIO
+}
 
 pub unsafe fn on_irq() {
     #[cfg(not(any(exti_g0, exti_l5)))]
@@ -296,6 +300,8 @@ pub(crate) unsafe fn init() {
 
     foreach_exti_irq!(enable_irq);
 
-    #[cfg(not(any(rcc_wb, rcc_wl5)))]
+    #[cfg(not(any(rcc_wb, rcc_wl5, rcc_f1)))]
     <crate::peripherals::SYSCFG as crate::rcc::sealed::RccPeripheral>::enable();
+    #[cfg(rcc_f1)]
+    <crate::peripherals::AFIO as crate::rcc::sealed::RccPeripheral>::enable();
 }

embassy-stm32/src/gpio.rs

@@ -18,6 +18,7 @@ pub enum Pull {
     Down,
 }
 
+#[cfg(gpio_v2)]
 impl From<Pull> for vals::Pupdr {
     fn from(pull: Pull) -> Self {
         use Pull::*;
@@ -36,11 +37,25 @@ impl From<Pull> for vals::Pupdr {
 pub enum Speed {
     Low,
     Medium,
-    #[cfg(not(syscfg_f0))]
+    #[cfg(not(any(syscfg_f0, gpio_v1)))]
     High,
     VeryHigh,
 }
 
+#[cfg(gpio_v1)]
+impl From<Speed> for vals::Mode {
+    fn from(speed: Speed) -> Self {
+        use Speed::*;
+
+        match speed {
+            Low => vals::Mode::OUTPUT2,
+            Medium => vals::Mode::OUTPUT,
+            VeryHigh => vals::Mode::OUTPUT50,
+        }
+    }
+}
+
+#[cfg(gpio_v2)]
 impl From<Speed> for vals::Ospeedr {
     fn from(speed: Speed) -> Self {
         use Speed::*;
@@ -68,9 +83,29 @@ impl<'d, T: Pin> Input<'d, T> {
         cortex_m::interrupt::free(|_| unsafe {
             let r = pin.block();
             let n = pin.pin() as usize;
+            #[cfg(gpio_v1)]
+            {
+                let crlh = if n < 8 { 0 } else { 1 };
+                match pull {
+                    Pull::Up => r.bsrr().write(|w| w.set_bs(n, true)),
+                    Pull::Down => r.bsrr().write(|w| w.set_br(n, true)),
+                    Pull::None => {}
+                }
+                if pull == Pull::None {
+                    r.cr(crlh)
+                        .modify(|w| w.set_cnf(n % 8, vals::Cnf::OPENDRAIN));
+                } else {
+                    r.cr(crlh)
+                        .modify(|w| w.set_cnf(n % 8, vals::Cnf::ALTPUSHPULL));
+                }
+                r.cr(crlh).modify(|w| w.set_mode(n % 8, vals::Mode::INPUT));
+            }
+            #[cfg(gpio_v2)]
+            {
                 r.pupdr().modify(|w| w.set_pupdr(n, pull.into()));
                 r.otyper().modify(|w| w.set_ot(n, vals::Ot::PUSHPULL));
                 r.moder().modify(|w| w.set_moder(n, vals::Moder::INPUT));
+            }
         });
 
         Self {
@@ -85,6 +120,13 @@ impl<'d, T: Pin> Drop for Input<'d, T> {
         cortex_m::interrupt::free(|_| unsafe {
             let r = self.pin.block();
             let n = self.pin.pin() as usize;
+            #[cfg(gpio_v1)]
+            {
+                let crlh = if n < 8 { 0 } else { 1 };
+                r.cr(crlh)
+                    .modify(|w| w.set_cnf(n % 8, vals::Cnf::OPENDRAIN));
+            }
+            #[cfg(gpio_v2)]
             r.pupdr().modify(|w| w.set_pupdr(n, vals::Pupdr::FLOATING));
         });
     }
@@ -129,10 +171,19 @@ impl<'d, T: Pin> Output<'d, T> {
         cortex_m::interrupt::free(|_| unsafe {
             let r = pin.block();
             let n = pin.pin() as usize;
+            #[cfg(gpio_v1)]
+            {
+                let crlh = if n < 8 { 0 } else { 1 };
+                r.cr(crlh).modify(|w| w.set_cnf(n % 8, vals::Cnf::PUSHPULL));
+                r.cr(crlh).modify(|w| w.set_mode(n % 8, speed.into()));
+            }
+            #[cfg(gpio_v2)]
+            {
                 r.pupdr().modify(|w| w.set_pupdr(n, vals::Pupdr::FLOATING));
                 r.otyper().modify(|w| w.set_ot(n, vals::Ot::PUSHPULL));
                 pin.set_speed(speed);
                 r.moder().modify(|w| w.set_moder(n, vals::Moder::OUTPUT));
+            }
         });
 
         Self {
@@ -147,8 +198,18 @@ impl<'d, T: Pin> Drop for Output<'d, T> {
         cortex_m::interrupt::free(|_| unsafe {
             let r = self.pin.block();
             let n = self.pin.pin() as usize;
+            #[cfg(gpio_v1)]
+            {
+                let crlh = if n < 8 { 0 } else { 1 };
+                r.cr(crlh)
+                    .modify(|w| w.set_cnf(n % 8, vals::Cnf::OPENDRAIN));
+                r.cr(crlh).modify(|w| w.set_mode(n % 8, vals::Mode::INPUT));
+            }
+            #[cfg(gpio_v2)]
+            {
                 r.pupdr().modify(|w| w.set_pupdr(n, vals::Pupdr::FLOATING));
                 r.moder().modify(|w| w.set_moder(n, vals::Moder::INPUT));
+            }
         });
     }
 }
@@ -207,10 +268,25 @@ impl<'d, T: Pin> OutputOpenDrain<'d, T> {
         cortex_m::interrupt::free(|_| unsafe {
             let r = pin.block();
             let n = pin.pin() as usize;
+            #[cfg(gpio_v1)]
+            {
+                let crlh = if n < 8 { 0 } else { 1 };
+                match pull {
+                    Pull::Up => r.bsrr().write(|w| w.set_bs(n, true)),
+                    Pull::Down => r.bsrr().write(|w| w.set_br(n, true)),
+                    Pull::None => {}
+                }
+                r.cr(crlh).modify(|w| w.set_mode(n % 8, speed.into()));
+                r.cr(crlh)
+                    .modify(|w| w.set_cnf(n % 8, vals::Cnf::OPENDRAIN));
+            }
+            #[cfg(gpio_v2)]
+            {
                 r.pupdr().modify(|w| w.set_pupdr(n, pull.into()));
                 r.otyper().modify(|w| w.set_ot(n, vals::Ot::OPENDRAIN));
                 pin.set_speed(speed);
                 r.moder().modify(|w| w.set_moder(n, vals::Moder::OUTPUT));
+            }
         });
 
         Self {
@@ -225,8 +301,18 @@ impl<'d, T: Pin> Drop for OutputOpenDrain<'d, T> {
         cortex_m::interrupt::free(|_| unsafe {
             let r = self.pin.block();
             let n = self.pin.pin() as usize;
+            #[cfg(gpio_v1)]
+            {
+                let crlh = if n < 8 { 0 } else { 1 };
+                r.cr(crlh)
+                    .modify(|w| w.set_cnf(n % 8, vals::Cnf::OPENDRAIN));
+                r.cr(crlh).modify(|w| w.set_mode(n % 8, vals::Mode::INPUT));
+            }
+            #[cfg(gpio_v2)]
+            {
                 r.pupdr().modify(|w| w.set_pupdr(n, vals::Pupdr::FLOATING));
                 r.moder().modify(|w| w.set_moder(n, vals::Moder::INPUT));
+            }
         });
     }
 }
@@ -307,6 +393,11 @@ pub(crate) mod sealed {
             }
         }
 
+        #[cfg(gpio_v1)]
+        unsafe fn set_as_af(&self, _af_num: u8, _af_type: OutputType) {
+            panic!("F1 alternate GPIO functions not supported yet!");
+        }
+        #[cfg(gpio_v2)]
         unsafe fn set_as_af(&self, af_num: u8, af_type: OutputType) {
             let pin = self._pin() as usize;
             let block = self.block();
@@ -333,11 +424,23 @@ pub(crate) mod sealed {
         unsafe fn set_as_analog(&self) {
             let pin = self._pin() as usize;
             let block = self.block();
+            #[cfg(gpio_v1)]
+            {
+                let crlh = if pin < 8 { 0 } else { 1 };
+                block
+                    .cr(crlh)
+                    .modify(|w| w.set_cnf(pin % 8, vals::Cnf::PUSHPULL));
+                block
+                    .cr(crlh)
+                    .modify(|w| w.set_mode(pin % 8, vals::Mode::INPUT));
+            }
+            #[cfg(gpio_v2)]
             block
                 .moder()
                 .modify(|w| w.set_moder(pin, vals::Moder::ANALOG));
         }
 
+        #[cfg(gpio_v2)]
         unsafe fn set_speed(&self, speed: Speed) {
             let pin = self._pin() as usize;
             self.block()

embassy-stm32/src/i2c/mod.rs

@@ -96,6 +96,7 @@ crate::pac::interrupts!(
     };
 );
 
+#[cfg(not(rcc_f1))]
 macro_rules! impl_pin {
     ($inst:ident, $pin:ident, $signal:ident, $af:expr) => {
         impl $signal<peripherals::$inst> for peripherals::$pin {}

embassy-stm32/src/rcc/f1/mod.rs

@@ -0,0 +1,214 @@
+use core::marker::PhantomData;
+
+use embassy::util::Unborrow;
+
+use crate::pac::flash::vals::Latency;
+use crate::pac::{FLASH, RCC};
+use crate::peripherals;
+use crate::time::Hertz;
+
+use cast::u32;
+
+use super::{set_freqs, Clocks};
+
+const HSI: u32 = 8_000_000;
+
+/// Configuration of the clocks
+///
+#[non_exhaustive]
+#[derive(Default)]
+pub struct Config {
+    pub hse: Option<Hertz>,
+
+    pub sys_ck: Option<Hertz>,
+    pub hclk: Option<Hertz>,
+    pub pclk1: Option<Hertz>,
+    pub pclk2: Option<Hertz>,
+    pub adcclk: Option<Hertz>,
+}
+
+pub struct Rcc<'d> {
+    inner: PhantomData<&'d ()>,
+    config: Config,
+}
+
+impl<'d> Rcc<'d> {
+    pub fn new(_rcc: impl Unborrow<Target = peripherals::RCC> + 'd, config: Config) -> Self {
+        Self {
+            inner: PhantomData,
+            config,
+        }
+    }
+
+    pub fn freeze(self) -> Clocks {
+        use crate::pac::rcc::vals::{Adcpre, Hpre, Pllmul, Pllsrc, Ppre1, Sw, Usbpre};
+
+        let pllsrcclk = self.config.hse.map(|hse| hse.0).unwrap_or(HSI / 2);
+        let sysclk = self.config.sys_ck.map(|sys| sys.0).unwrap_or(pllsrcclk);
+        let pllmul = sysclk / pllsrcclk;
+
+        let (pllmul_bits, real_sysclk) = if pllmul == 1 {
+            (None, self.config.hse.map(|hse| hse.0).unwrap_or(HSI))
+        } else {
+            let pllmul = core::cmp::min(core::cmp::max(pllmul, 1), 16);
+            (Some(pllmul as u8 - 2), pllsrcclk * pllmul)
+        };
+
+        assert!(real_sysclk <= 72_000_000);
+
+        let hpre_bits = self
+            .config
+            .hclk
+            .map(|hclk| match real_sysclk / hclk.0 {
+                0 => unreachable!(),
+                1 => 0b0111,
+                2 => 0b1000,
+                3..=5 => 0b1001,
+                6..=11 => 0b1010,
+                12..=39 => 0b1011,
+                40..=95 => 0b1100,
+                96..=191 => 0b1101,
+                192..=383 => 0b1110,
+                _ => 0b1111,
+            })
+            .unwrap_or(0b0111);
+
+        let hclk = if hpre_bits >= 0b1100 {
+            real_sysclk / (1 << (hpre_bits - 0b0110))
+        } else {
+            real_sysclk / (1 << (hpre_bits - 0b0111))
+        };
+
+        assert!(hclk <= 72_000_000);
+
+        let ppre1_bits = self
+            .config
+            .pclk1
+            .map(|pclk1| match hclk / pclk1.0 {
+                0 => unreachable!(),
+                1 => 0b011,
+                2 => 0b100,
+                3..=5 => 0b101,
+                6..=11 => 0b110,
+                _ => 0b111,
+            })
+            .unwrap_or(0b011);
+
+        let ppre1: i32 = 1 << (ppre1_bits - 0b011);
+        let pclk1 = hclk / u32(ppre1).unwrap();
+        let timer_mul1 = if ppre1 == 1 { 1 } else { 2 };
+
+        assert!(pclk1 <= 36_000_000);
+
+        let ppre2_bits = self
+            .config
+            .pclk2
+            .map(|pclk2| match hclk / pclk2.0 {
+                0 => unreachable!(),
+                1 => 0b011,
+                2 => 0b100,
+                3..=5 => 0b101,
+                6..=11 => 0b110,
+                _ => 0b111,
+            })
+            .unwrap_or(0b011);
+
+        let ppre2: i32 = 1 << (ppre2_bits - 0b011);
+        let pclk2 = hclk / u32(ppre2).unwrap();
+        let timer_mul2 = if ppre2 == 1 { 1 } else { 2 };
+
+        assert!(pclk2 <= 72_000_000);
+
+        // Only needed for stm32f103?
+        // NOTE(safety) Atomic write
+        unsafe {
+            FLASH.acr().write(|w| {
+                w.set_latency(if real_sysclk <= 24_000_000 {
+                    Latency(0b000)
+                } else if real_sysclk <= 48_000_000 {
+                    Latency(0b001)
+                } else {
+                    Latency(0b010)
+                });
+            })
+        }
+
+        // the USB clock is only valid if an external crystal is used, the PLL is enabled, and the
+        // PLL output frequency is a supported one.
+        // usbpre == false: divide clock by 1.5, otherwise no division
+        let (usbpre, _usbclk_valid) = match (self.config.hse, pllmul_bits, real_sysclk) {
+            (Some(_), Some(_), 72_000_000) => (false, true),
+            (Some(_), Some(_), 48_000_000) => (true, true),
+            _ => (true, false),
+        };
+
+        let apre_bits: u8 = self
+            .config
+            .adcclk
+            .map(|adcclk| match pclk2 / adcclk.0 {
+                0..=2 => 0b00,
+                3..=4 => 0b01,
+                5..=7 => 0b10,
+                _ => 0b11,
+            })
+            .unwrap_or(0b11);
+
+        let apre = (apre_bits + 1) << 1;
+        let adcclk = pclk2 / u32(apre);
+
+        assert!(adcclk <= 14_000_000);
+
+        unsafe {
+            if self.config.hse.is_some() {
+                // enable HSE and wait for it to be ready
+                RCC.cr().modify(|w| w.set_hseon(true));
+                while !RCC.cr().read().hserdy() {}
+            }
+
+            if let Some(pllmul_bits) = pllmul_bits {
+                // enable PLL and wait for it to be ready
+                RCC.cfgr().modify(|w| {
+                    w.set_pllmul(Pllmul(pllmul_bits));
+                    w.set_pllsrc(Pllsrc(self.config.hse.is_some() as u8));
+                });
+
+                RCC.cr().modify(|w| w.set_pllon(true));
+                while !RCC.cr().read().pllrdy() {}
+            }
+
+            // Only needed for stm32f103?
+            RCC.cfgr().modify(|w| {
+                w.set_adcpre(Adcpre(apre_bits));
+                w.set_ppre2(Ppre1(ppre2_bits));
+                w.set_ppre1(Ppre1(ppre1_bits));
+                w.set_hpre(Hpre(hpre_bits));
+                w.set_usbpre(Usbpre(usbpre as u8));
+                w.set_sw(Sw(if pllmul_bits.is_some() {
+                    // PLL
+                    0b10
+                } else if self.config.hse.is_some() {
+                    // HSE
+                    0b1
+                } else {
+                    // HSI
+                    0b0
+                }));
+            });
+        }
+
+        Clocks {
+            sys: Hertz(real_sysclk),
+            apb1: Hertz(pclk1),
+            apb2: Hertz(pclk2),
+            apb1_tim: Hertz(pclk1 * timer_mul1),
+            apb2_tim: Hertz(pclk2 * timer_mul2),
+            ahb: Hertz(hclk),
+        }
+    }
+}
+
+pub unsafe fn init(config: Config) {
+    let rcc = Rcc::new(<peripherals::RCC as embassy::util::Steal>::steal(), config);
+    let clocks = rcc.freeze();
+    set_freqs(clocks);
+}

embassy-stm32/src/rcc/mod.rs

@@ -27,7 +27,7 @@ pub struct Clocks {
     #[cfg(rcc_wl5)]
     pub apb3: Hertz,
 
-    #[cfg(any(rcc_l0, rcc_l1, rcc_f0, rcc_f0x0, rcc_g0))]
+    #[cfg(any(rcc_l0, rcc_l1, rcc_f0, rcc_f1, rcc_f0x0, rcc_g0))]
     pub ahb: Hertz,
 
     #[cfg(any(rcc_l4, rcc_f4, rcc_h7, rcc_wb, rcc_wl5))]
@@ -79,6 +79,9 @@ cfg_if::cfg_if! {
     } else if #[cfg(rcc_l4)] {
         mod l4;
         pub use l4::*;
+    } else if #[cfg(rcc_f1)] {
+        mod f1;
+        pub use f1::*;
     } else if #[cfg(rcc_f4)] {
         mod f4;
         pub use f4::*;

embassy-stm32/src/usart/mod.rs

@@ -127,6 +127,7 @@ crate::pac::interrupts!(
     };
 );
 
+#[cfg(not(rcc_f1))]
 macro_rules! impl_pin {
     ($inst:ident, $pin:ident, $signal:ident, $af:expr) => {
         impl sealed::$signal<peripherals::$inst> for peripherals::$pin {

examples/stm32f1/.cargo/config.toml

@@ -0,0 +1,18 @@
+[target.'cfg(all(target_arch = "arm", target_os = "none"))']
+# replace STM32F103C8 with your chip as listed in `probe-run --list-chips`
+runner = "probe-run --chip STM32F103C8"
+
+rustflags = [
+  # LLD (shipped with the Rust toolchain) is used as the default linker
+  "-C", "link-arg=--nmagic",
+  "-C", "link-arg=-Tlink.x",
+  "-C", "link-arg=-Tdefmt.x",
+
+  # Code-size optimizations.
+  "-Z", "trap-unreachable=no",
+  "-C", "inline-threshold=5",
+  "-C", "no-vectorize-loops",
+]
+
+[build]
+target = "thumbv7m-none-eabi"

examples/stm32f1/Cargo.toml

@@ -0,0 +1,35 @@
+[package]
+authors = ["Dario Nieuwenhuis <dirbaio@dirbaio.net>"]
+edition = "2018"
+name = "embassy-stm32f1-examples"
+version = "0.1.0"
+resolver = "2"
+
+[features]
+default = [
+    "defmt-default",
+]
+defmt-default = []
+defmt-trace = []
+defmt-debug = []
+defmt-info = []
+defmt-warn = []
+defmt-error = []
+
+[dependencies]
+embassy = { version = "0.1.0", path = "../../embassy", features = ["defmt", "defmt-trace"] }
+embassy-traits = { version = "0.1.0", path = "../../embassy-traits", features = ["defmt"] }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["defmt", "defmt-trace", "stm32f103c8", "unstable-pac", "memory-x", "time-driver-tim2"]  }
+embassy-hal-common = {version = "0.1.0", path = "../../embassy-hal-common" }
+
+defmt = "0.2.3"
+defmt-rtt = "0.2.0"
+
+cortex-m = "0.7.3"
+cortex-m-rt = "0.7.0"
+embedded-hal = "0.2.6"
+panic-probe = { version = "0.2.0", features = ["print-defmt"] }
+futures = { version = "0.3.17", default-features = false, features = ["async-await"] }
+rtt-target = { version = "0.3.1", features = ["cortex-m"] }
+heapless = { version = "0.7.5", default-features = false }
+nb = "1.0.0"

examples/stm32f1/src/bin/blinky.rs

@@ -0,0 +1,29 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+use embassy::executor::Spawner;
+use embassy::time::{Duration, Timer};
+use embassy_stm32::gpio::{Level, Output, Speed};
+use embassy_stm32::Peripherals;
+use embedded_hal::digital::v2::OutputPin;
+use example_common::*;
+
+#[embassy::main]
+async fn main(_spawner: Spawner, p: Peripherals) {
+    info!("Hello World!");
+
+    let mut led = Output::new(p.PC13, Level::High, Speed::Low);
+
+    loop {
+        info!("high");
+        unwrap!(led.set_high());
+        Timer::after(Duration::from_millis(300)).await;
+
+        info!("low");
+        unwrap!(led.set_low());
+        Timer::after(Duration::from_millis(300)).await;
+    }
+}

examples/stm32f1/src/bin/hello.rs

@@ -0,0 +1,27 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::info;
+use embassy::executor::Spawner;
+use embassy::time::{Duration, Timer};
+use embassy_stm32::time::Hertz;
+use embassy_stm32::Config;
+use embassy_stm32::Peripherals;
+
+#[path = "../example_common.rs"]
+mod example_common;
+
+fn config() -> Config {
+    let mut config = Config::default();
+    config.rcc.sys_ck = Some(Hertz(36_000_000));
+    config
+}
+
+#[embassy::main(config = "config()")]
+async fn main(_spawner: Spawner, _p: Peripherals) -> ! {
+    loop {
+        info!("Hello World!");
+        Timer::after(Duration::from_secs(1)).await;
+    }
+}

examples/stm32f1/src/example_common.rs

@@ -0,0 +1,17 @@
+#![macro_use]
+
+use defmt_rtt as _; // global logger
+use panic_probe as _;
+
+pub use defmt::*;
+
+use core::sync::atomic::{AtomicUsize, Ordering};
+
+defmt::timestamp! {"{=u64}", {
+        static COUNT: AtomicUsize = AtomicUsize::new(0);
+        // NOTE(no-CAS) `timestamps` runs with interrupts disabled
+        let n = COUNT.load(Ordering::Relaxed);
+        COUNT.store(n + 1, Ordering::Relaxed);
+        n as u64
+    }
+}

stm32-gen-features/src/lib.rs

@@ -2,8 +2,9 @@
 
 use std::{iter::FilterMap, path::Path, slice::Iter};
 
-const SUPPORTED_FAMILIES: [&str; 9] = [
+const SUPPORTED_FAMILIES: [&str; 10] = [
     "stm32f0",
+    "stm32f1",
     "stm32f4",
     "stm32g0",
     "stm32l0",