From ddd8932ffac52287928503ad5c21eaac8a19615e652eeb8c1aed0d10642c20db Mon Sep 17 00:00:00 2001
From: localhorst <localhorst@mosad.xyz>
Date: Sat, 6 Sep 2025 00:05:39 +0200
Subject: [PATCH] basic button toggle

---
 main.c | 126 +++++++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 96 insertions(+), 30 deletions(-)

diff --git a/main.c b/main.c
index 56269b9..a1aeab8 100644
--- a/main.c
+++ b/main.c
@@ -15,22 +15,25 @@
 #define PA1_SET_MASK 0x02 ///< LED 1–2
 #define PA2_SET_MASK 0x04 ///< LED 3–6
 #define PA3_SET_MASK 0x08 ///< LED 7–8
-#define PA6_SET_MASK 0x40 ///< Green LED
+#define PA6_SET_MASK 0x40 ///< Switch input (was green LED pin) TODO: Switch to PA0
 #define PA7_SET_MASK 0x80 ///< Red LED
 /** @} */
 
-/** @brief Main loop delay in ms (system tick). */
-#define MAIN_LOOP_SLEEP 10U
+#define MAIN_LOOP_SLEEP 10U         // Main loop delay in ms (system tick)
+#define BUTTON_PRESS_DURATION 1000U // Button needs to be pressed for at least 1000ms
 
 /** @brief Convert milliseconds to system ticks (integer division). */
 #define MS_TO_TICKS(ms) ((ms) / MAIN_LOOP_SLEEP)
 
-/** @brief Global flag: enable or disable LED output. */
+/** @brief Global flags */
 volatile bool bLedEnabled = true;
+volatile bool bBtnPressed = false;
 
 // Function forward declarations
 void blinkLed(void);
 static inline void leds_off(void);
+static inline void leds_on(void);
+static void handleSwitch(void);
 
 /**
  * @brief Main entry point.
@@ -43,19 +46,45 @@ int main(void)
 {
     // --- configure LED pins as outputs ---
     VPORTA.DIR = (PA1_SET_MASK | PA2_SET_MASK | PA3_SET_MASK |
-                  PA6_SET_MASK | PA7_SET_MASK);
+                  /*PA6_SET_MASK |*/ // PA6 now input (switch)
+                  PA7_SET_MASK);
+
+    // Configure PA6 as input with pull-up TODO: Switch to PA0
+    VPORTA.DIR &= ~PA6_SET_MASK;       // Input
+    PORTA.PIN6CTRL = PORT_PULLUPEN_bm; // Pull-up enabled
 
     // --- ensure all LEDs off at startup ---
     leds_off();
-    VPORTA.OUT &= (uint8_t)~(PA6_SET_MASK | PA7_SET_MASK);
+    VPORTA.OUT &= (uint8_t) ~(PA7_SET_MASK);
+
+    bool bLedEnabledOld = bLedEnabled;
 
     while (true)
     {
-        // TODO: add status LED handling if needed
-        // VPORTA.OUT ^= PA6_SET_MASK; // toggle green LED
-        // VPORTA.OUT ^= PA7_SET_MASK; // toggle red LED
+        handleSwitch(); // check switch state
 
-        blinkLed();
+        if (bBtnPressed)
+        {
+            leds_on();
+        }
+        else
+        {
+            leds_off();
+        }
+
+        if (bLedEnabledOld != bLedEnabled)
+        {
+            bLedEnabledOld = bLedEnabled;
+            leds_off();
+            _delay_ms(1000);
+        }
+        else
+        {
+            if ((bLedEnabled) && (!bBtnPressed))
+            {
+                blinkLed();
+            }
+        }
 
         _delay_ms(MAIN_LOOP_SLEEP);
     }
@@ -68,32 +97,72 @@ int main(void)
  */
 static inline void leds_off(void)
 {
-    VPORTA.OUT &= (uint8_t)~(PA1_SET_MASK | PA2_SET_MASK | PA3_SET_MASK);
+    VPORTA.OUT &= (uint8_t) ~(PA1_SET_MASK | PA2_SET_MASK | PA3_SET_MASK);
 }
 
 /**
- * @brief LED blink state machine.
+ * @brief Switch on all controlled LEDs (PA1, PA2, PA3).
  *
- * Implements the following repeating sequence (non-blocking):
+ * @note Declared inline for speed (single instruction sequence).
+ */
+static inline void leds_on(void)
+{
+    VPORTA.OUT |= (PA1_SET_MASK | PA2_SET_MASK | PA3_SET_MASK);
+}
+
+/**
+ * @brief Handle momentary switch input on PA6. TODO: Switch to PA0
  *
- * Normal cycle:
- *   - Step 0:  all off, wait 250 ms
- *   - Step 2:  LED 1–2 + 7–8 on, wait 50 ms
- *   - Step 5:  all off, wait 100 ms
- *   - Step 7:  LED 1–2 + 7–8 on, wait 50 ms
- *   - Step 10: all off, wait 250 ms
- *   - Step 12: LED 3–6 on, wait 50 ms
- *   - Step 14: all off, wait 100 ms
- *   - Step 16: LED 3–6 on, wait 50 ms
- *   - Step 18: all off, wait 250 ms → restart
+ * A press longer than 2 seconds toggles ::bLedEnabled.
+ * Uses simple state and counters for debouncing and long-press detection.
+ */
+static void handleSwitch(void)
+{
+    static uint16_t pressTicks = 0;  ///< press duration counter
+    static bool prevPressed = false; ///< previous switch state
+
+    bool pressed = !(VPORTA.IN & PA6_SET_MASK); // active-low
+
+    if (pressed)
+    {
+        bBtnPressed = true;
+        if (pressTicks < 0xFFFF)
+        {
+            // prevent overflow
+            pressTicks++;
+        }
+    }
+    else
+    {
+        bBtnPressed = false;
+        pressTicks = 0;
+    }
+
+    if (prevPressed && pressTicks >= MS_TO_TICKS(BUTTON_PRESS_DURATION))
+    {
+        // long press detected → toggle blinking
+        bLedEnabled = !bLedEnabled;
+    }
+
+    prevPressed = pressed;
+}
+
+/**
+ * @brief LED blink state machine (bike rear light style).
+ *
+ * Implements a "rounded" pulsing blink sequence:
+ *
+ * Normal cycle (~1 s total):
+ *   - Step 0:  all off, wait 100 ms
+ *   - Step 1:  LED 1–2 + 7–8 ON, wait 100 ms
+ *   - Step 2:  all LEDs ON, wait 200 ms
+ *   - Step 3:  only LED 1–2 ON, wait 100 ms
+ *   - Step 4:  all off, wait 400 ms → restart
  *
  * Special behavior:
- *   - Every 3rd cycle, after step 18, all LEDs (PA1, PA2, PA3) are switched on for 250 ms.
+ *   - Every 3rd cycle, after step 4, all LEDs are switched on for 300 ms.
  *
  * Timing is based on @ref MAIN_LOOP_SLEEP ticks.
- *
- * @note Must be called periodically every 10 ms from the main loop.
- * @note Depends on global flag ::bLedEnabled. If false, does nothing.
  */
 void blinkLed(void)
 {
@@ -107,9 +176,6 @@ void blinkLed(void)
     static uint8_t state = 0;    ///< current step in the sequence
     static uint8_t cycle = 0;    ///< cycle counter (0–2)
 
-    if (!bLedEnabled)
-        return;
-
     counter++;
 
     switch (state)