h7: implement RTC and LSE clock configuration

2 files changed, 41 insertions, 1 deletions

diff --git a/examples/stm32h7/Cargo.toml b/examples/stm32h7/Cargo.toml
index 3a3927a9a..7bcdf2b3e 100644
--- a/examples/stm32h7/Cargo.toml
+++ b/examples/stm32h7/Cargo.toml
@@ -6,7 +6,7 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 # Change stm32h743bi to your chip name, if necessary.
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32h743bi", "time-driver-any", "exti", "memory-x", "unstable-pac", "unstable-traits"] }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "stm32h743bi", "time-driver-any", "exti", "memory-x", "unstable-pac", "unstable-traits", "chrono"] }
 embassy-sync = { version = "0.3.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.3.0", path = "../../embassy-executor", features = ["nightly", "arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.1.3", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "unstable-traits", "tick-hz-32_768"] }
@@ -32,6 +32,7 @@ micromath = "2.0.0"
 stm32-fmc = "0.3.0"
 embedded-storage = "0.3.0"
 static_cell = { version = "1.1", features = ["nightly"]}
+chrono = { version = "^0.4", default-features = false }
 
 # cargo build/run
 [profile.dev]
diff --git a/examples/stm32h7/src/bin/rtc.rs b/examples/stm32h7/src/bin/rtc.rs
new file mode 100644
index 000000000..eeb94073b
--- /dev/null
+++ b/examples/stm32h7/src/bin/rtc.rs
@@ -0,0 +1,39 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use chrono::{NaiveDate, NaiveDateTime};
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::rcc::Lse;
+use embassy_stm32::rtc::{Rtc, RtcClockSource, RtcConfig};
+use embassy_stm32::Config;
+use embassy_time::{Duration, Timer};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = {
+        let mut config = Config::default();
+        config.rcc.lse = Some(Lse::Oscillator);
+        config.rcc.rtc_mux = Some(RtcClockSource::LSE);
+        embassy_stm32::init(config)
+    };
+    info!("Hello World!");
+
+    let now = NaiveDate::from_ymd_opt(2020, 5, 15)
+        .unwrap()
+        .and_hms_opt(10, 30, 15)
+        .unwrap();
+
+    let mut rtc = Rtc::new(p.RTC, RtcConfig::default());
+    info!("Got RTC! {:?}", now.timestamp());
+
+    rtc.set_datetime(now.into()).expect("datetime not set");
+
+    // In reality the delay would be much longer
+    Timer::after(Duration::from_millis(20000)).await;
+
+    let then: NaiveDateTime = rtc.now().unwrap().into();
+    info!("Got RTC! {:?}", then.timestamp());
+}