Merge branch 'main' into feature/energy-saving

main.c

@@ -1,7 +1,6 @@
 /**
  * @file main.c
- * @brief Bike rear light implementation for ATTINY202.
+ * @brief Bike rear light implementation for ATTINY202 with low-power standby.
- *
  */
 
 #include <stdint.h>
@@ -18,13 +17,12 @@
 #define PA6_SET_MASK 0x40    ///< Green LED pin
 #define PA7_SET_MASK 0x80    ///< Red LED
 
-#define MAIN_LOOP_SLEEP 10U                 // Main loop delay in ms
+#define MAIN_LOOP_SLEEP 50U                 // Loop period in ms
 #define BUTTON_LONG_PRESS_DURATION_MS 1000U // Long press threshold
 #define BUTTON_IGNORE_DURATION_MS 2000U     // Time button ignored after long press
 #define BUTTON_CONFIRMATION_BLINK_LOOPS 10U // Blink animation for confirmation
 #define BUTTON_CONFIRMATION_BLINK_DURATION_MS 50U
 
-/** Convert milliseconds to system ticks */
 #define MS_TO_TICKS(ms) ((ms) / MAIN_LOOP_SLEEP)
 
 /** Global flags */
@@ -40,9 +38,25 @@ static void handleSwitch(void);
 static void software_reset(void);
 ISR(PORTA_PORT_vect);
 
-/**
+/* --- Timer init: Use RTC PIT for periodic wake-up --- */
- * @brief Main entry point
+void init_timer(void)
- */
+{
+    RTC.CLKSEL = RTC_CLKSEL_INT1K_gc; // 1 kHz ULP clock for RTC
+    while (RTC.STATUS > 0)
+    {
+    } // Wait for sync
+
+    RTC.PITINTCTRL = RTC_PI_bm;        // Enable PIT interrupt
+    RTC.PITCTRLA = RTC_PERIOD_CYC64_gc // ≈64 ms wake-up (~50 ms)
+                   | RTC_PITEN_bm;     // Enable PIT
+}
+
+ISR(RTC_PIT_vect)
+{
+    RTC.PITINTFLAGS = RTC_PI_bm; // Clear interrupt flag
+}
+
+/* --- MAIN --- */
 int main(void)
 {
     // Configure LED pins as outputs
@@ -58,7 +72,13 @@ int main(void)
 
     bool bLedEnabledOld = bLedEnabled;
 
-    while (true)
+    cli();
+    init_timer();
+    sei();
+
+    set_sleep_mode(SLEEP_MODE_STANDBY);
+
+    while (1)
     {
         handleSwitch(); // Check switch state
 
@@ -107,7 +127,9 @@ int main(void)
             }
         }
 
-        _delay_ms(MAIN_LOOP_SLEEP);
+        sleep_enable();
+        sleep_cpu(); // Sleep until PIT wakes
+        sleep_disable();
     }
 }
 
@@ -324,7 +346,7 @@ void blinkLed(bool resetCounters)
         if (counter >= T250)
         {
             counter = 0;
-            state = 0; // restart normal sequence
+            state = 0;
         }
         break;
     }