From 53cb84d3d65b96b5f92f434b113cffe62810c0ad Mon Sep 17 00:00:00 2001
From: Dion Dokter <diondokter@gmail.com>
Date: Tue, 16 Apr 2024 15:24:20 +0200
Subject: [PATCH] Added RTC example

---
 examples/stm32u0/Cargo.toml     |  3 +-
 examples/stm32u0/src/bin/rtc.rs | 49 +++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+), 1 deletion(-)
 create mode 100644 examples/stm32u0/src/bin/rtc.rs

diff --git a/examples/stm32u0/Cargo.toml b/examples/stm32u0/Cargo.toml
index 64fd837a2..5868372dd 100644
--- a/examples/stm32u0/Cargo.toml
+++ b/examples/stm32u0/Cargo.toml
@@ -6,7 +6,7 @@ license = "MIT OR Apache-2.0"
 
 [dependencies]
 # Change stm32u083rc to your chip name, if necessary.
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = [ "defmt", "time-driver-any", "stm32u083rc", "memory-x", "unstable-pac", "exti"]  }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = [ "defmt", "time-driver-any", "stm32u083rc", "memory-x", "unstable-pac", "exti", "chrono"]  }
 embassy-sync = { version = "0.5.0", path = "../../embassy-sync", features = ["defmt"] }
 embassy-executor = { version = "0.5.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.3.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime", "tick-hz-32_768"] }
@@ -23,6 +23,7 @@ futures = { version = "0.3.17", default-features = false, features = ["async-awa
 heapless = { version = "0.8", default-features = false }
 
 micromath = "2.0.0"
+chrono = { version = "0.4.38", default-features = false }
 
 [profile.release]
 debug = 2
diff --git a/examples/stm32u0/src/bin/rtc.rs b/examples/stm32u0/src/bin/rtc.rs
new file mode 100644
index 000000000..72fa0fde4
--- /dev/null
+++ b/examples/stm32u0/src/bin/rtc.rs
@@ -0,0 +1,49 @@
+#![no_std]
+#![no_main]
+
+use chrono::{NaiveDate, NaiveDateTime};
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_stm32::rtc::{Rtc, RtcConfig};
+use embassy_stm32::Config;
+use embassy_time::Timer;
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let mut config = Config::default();
+    {
+        use embassy_stm32::rcc::*;
+        config.rcc.sys = Sysclk::PLL1_R;
+        config.rcc.hsi = true;
+        config.rcc.pll = Some(Pll {
+            source: PllSource::HSI, // 16 MHz
+            prediv: PllPreDiv::DIV1,
+            mul: PllMul::MUL7, // 16 * 7 = 112 MHz
+            divp: None,
+            divq: None,
+            divr: Some(PllRDiv::DIV2), // 112 / 2 = 56 MHz
+        });
+        config.rcc.ls = LsConfig::default();
+    }
+
+    let p = 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.and_utc().timestamp());
+
+    rtc.set_datetime(now.into()).expect("datetime not set");
+
+    // In reality the delay would be much longer
+    Timer::after_millis(20000).await;
+
+    let then: NaiveDateTime = rtc.now().unwrap().into();
+    info!("Got RTC! {:?}", then.and_utc().timestamp());
+}