From 33543099c2d843208942180ee6a6345ce72043e7 Mon Sep 17 00:00:00 2001
From: Priec <filippriec@gmail.com>
Date: Wed, 3 Dec 2025 16:52:30 +0100
Subject: [PATCH] split the wakeup now, properly working

---
 semestralka_2/src/bin/main.rs      | 33 ++++++++----------------------
 semestralka_2/src/config.rs        |  2 ++
 semestralka_2/src/sleep/standby.rs | 12 +++++++++++
 semestralka_2/src/wakeup/iwdg.rs   | 31 ++++++++++++++++++++++++++++
 4 files changed, 53 insertions(+), 25 deletions(-)

diff --git a/semestralka_2/src/bin/main.rs b/semestralka_2/src/bin/main.rs
index 65ba86c..eb6fdd9 100644
--- a/semestralka_2/src/bin/main.rs
+++ b/semestralka_2/src/bin/main.rs
@@ -3,7 +3,6 @@
 #![no_main]
 
 use defmt::*;
-use core::ptr::addr_of_mut;
 use embassy_stm32::pac;
 use embassy_executor::Spawner;
 use embassy_futures::yield_now;
@@ -12,7 +11,6 @@ use embassy_stm32::peripherals;
 use embassy_stm32::Config;
 use embassy_stm32::usart::{BufferedUart, Config as UsartConfig, BufferedInterruptHandler};
 use embassy_stm32::gpio::{Output, Level, Speed};
-use embassy_stm32::wdg::IndependentWatchdog;
 use embassy_time::{Duration, Timer};
 
 use static_cell::StaticCell;
@@ -20,6 +18,7 @@ use dma_gpio::config::{
     BAUD, PIPE_HW_RX, PIPE_HW_TX,
 };
 use dma_gpio::hw_uart_pc::{driver::uart_task, usart1};
+use dma_gpio::wakeup::iwdg::{clear_wakeup_flags, init_watchdog};
 use {defmt_rtt as _, panic_probe as _};
 
 bind_interrupts!(struct Irqs {
@@ -30,8 +29,6 @@ unsafe extern "C" {
     fn HAL_PWR_EnterSTANDBYMode();
 }
 
-const PWR_FLAG_SBF: u32 = 1 << 1;
-
 #[embassy_executor::main]
 async fn main(spawner: Spawner) {
     info!("boot");
@@ -40,16 +37,10 @@ async fn main(spawner: Spawner) {
     let _led_ground = Output::new(p.PB0, Level::Low, Speed::Low);
     info!("init m8");
 
-    // Clearing after the wakeup 
-    let rcc = pac::RCC;
-    rcc.csr().write(|w| w.set_rmvf(true));
-    
-    // Check wake source
-    let pwr = pac::PWR;
-    if pwr.sr().read().sbf() {
-        info!("Woke from Standby via watchdog");
-        pwr.sr().write(|w| w.set_sbf(true));
-    }
+    clear_wakeup_flags();
+
+    led.set_high();
+    info!("LED ON (MCU awake)");
 
     // HARDWARE UART to the PC
     let mut cfg = UsartConfig::default();
@@ -74,19 +65,10 @@ async fn main(spawner: Spawner) {
     info!("DBGMCU CR: dbg_stop={}, dbg_standby={}", cr.dbg_stop(), cr.dbg_standby());
 
     // MAIN LOOP
-    info!("tick start");
-    led.set_high();
-    info!("LED IS HIGH");
+    info!("Preparing for standby...");
     Timer::after(Duration::from_millis(500)).await;
-    led.set_low();
-    info!("LED IS LOW");
-    Timer::after(Duration::from_millis(500)).await;
-    led.set_high();
-    info!("LED IS HIGH");
 
-    info!("Iwdg init");
-    let mut watchdog = IndependentWatchdog::new(p.IWDG, 2_000_000); // 2 seconds
-    watchdog.unleash();
+    init_watchdog(p.IWDG).await;
     Timer::after(Duration::from_millis(10)).await;
                         
     unsafe {
@@ -96,5 +78,6 @@ async fn main(spawner: Spawner) {
 
     loop {
         cortex_m::asm::wfi();
+        yield_now().await;
     }
 }
diff --git a/semestralka_2/src/config.rs b/semestralka_2/src/config.rs
index 1334716..13ff5f8 100644
--- a/semestralka_2/src/config.rs
+++ b/semestralka_2/src/config.rs
@@ -6,5 +6,7 @@ pub const BAUD: u32 = 9_600;
 pub const PIPE_HW_TX_SIZE: usize = 1024;
 pub const PIPE_HW_RX_SIZE: usize = 1024;
 
+pub const WATCHDOG_TIMEOUT_US: u32 = 2_000_000;  // 2 seconds
+
 pub static PIPE_HW_TX: Pipe<CriticalSectionRawMutex, PIPE_HW_TX_SIZE> = Pipe::new();
 pub static PIPE_HW_RX: Pipe<CriticalSectionRawMutex, PIPE_HW_RX_SIZE> = Pipe::new();
diff --git a/semestralka_2/src/sleep/standby.rs b/semestralka_2/src/sleep/standby.rs
index 421dfa3..f1374f8 100644
--- a/semestralka_2/src/sleep/standby.rs
+++ b/semestralka_2/src/sleep/standby.rs
@@ -1 +1,13 @@
 // src/sleep/standby.rs
+
+pub fn enter_standby() -> ! {
+    unsafe extern "C" {
+        fn HAL_PWR_EnterSTANDBYMode();
+    }
+    
+    unsafe {
+        HAL_PWR_EnterSTANDBYMode();
+    }
+    
+    cortex_m::asm::udf(); // never happen marker
+}
diff --git a/semestralka_2/src/wakeup/iwdg.rs b/semestralka_2/src/wakeup/iwdg.rs
index d6a2266..977d7af 100644
--- a/semestralka_2/src/wakeup/iwdg.rs
+++ b/semestralka_2/src/wakeup/iwdg.rs
@@ -1,3 +1,34 @@
 // src/wakeup/iwdg.rs
 
+use defmt::info;
+use embassy_stm32::peripherals;
+use embassy_stm32::wdg::IndependentWatchdog;
+use embassy_stm32::Peri;
+use embassy_time::{Duration, Timer};
+use embassy_stm32::pac;
 
+use crate::config::WATCHDOG_TIMEOUT_US;
+
+pub fn clear_wakeup_flags() {
+    info!("Clearing wakeup flags...");
+
+    // Clear reset flags
+    // let rcc = unsafe { &*pac::RCC::ptr() };
+    let rcc = pac::RCC;
+    rcc.csr().write(|w| w.set_rmvf(true));
+
+    // Check and clear Standby wakeup flag
+    // let pwr = unsafe { &*pac::PWR::ptr() };
+    let pwr = pac::PWR;
+    if pwr.sr().read().sbf() {
+        info!("Woke from Standby mode");
+        pwr.sr().write(|w| w.set_sbf(true));
+    }
+}
+
+pub async fn init_watchdog(iwdg: Peri<'_, peripherals::IWDG>) {
+    info!("Initializing watchdog after watchdog wake...");
+    let mut watchdog = IndependentWatchdog::new(iwdg, WATCHDOG_TIMEOUT_US);
+    watchdog.unleash();
+    Timer::after(Duration::from_millis(10)).await;
+}