Simple rtc example using the very inaccurate LSI clock source for the rtc

Author: usbalbin

examples/rtc.rs

@@ -0,0 +1,50 @@
+#![no_main]
+#![no_std]
+
+use hal::{
+    delay::SYSTDelayExt,
+    rcc::{Config, RccExt},
+    stm32::Peripherals,
+    time::{Time, Date, Year, Month, MonthDay, Hour, Minute, Second, ExtU32},
+    hal::prelude::*, rtc::RtcExt
+};
+use stm32g4xx_hal as hal;
+
+use cortex_m_rt::entry;
+
+use utils::logger::info;
+
+#[macro_use]
+mod utils;
+
+#[entry]
+fn main() -> ! {
+    utils::logger::init();
+
+    info!("start");
+
+    let dp = Peripherals::take().unwrap();
+    let cp = cortex_m::Peripherals::take().expect("cannot take core peripherals");
+
+    info!("rcc");
+
+    let rcc = dp.RCC.constrain();
+    let mut rcc = rcc.freeze(Config::hsi());
+
+    info!("Setup rtc");
+    let mut delay = cp.SYST.delay(&rcc.clocks);
+    let mut rtc = dp
+        .RTC
+        .constrain(&mut rcc);
+
+    info!("Setup date");
+    rtc.set_date(&Date::new(Year(2023), Month(6), MonthDay(4)));
+    rtc.set_time(&Time::new(18.hours(), 43.minutes(), 2.secs(), true));
+
+    info!("Enter Loop");
+
+    loop {
+        info!("Timestamp: {} {}", rtc.get_date(), rtc.get_time());
+        delay.delay_ms(500);
+    }
+}