Add extern irq from encoder button

SW/main.cpp

 #include <avr/io.h>
+#include <avr/interrupt.h>
 #include <util/delay.h>
 #include <stdint.h>
 
@@ -14,19 +15,41 @@ static void uart_string(const char *text);
 
 static void wellcome();
 
+gpio led(PORTD, PIN0_bm);
+
+ISR(PORTA_INT0_vect)
+{
+    led.toggle();
+}
+
+ISR(BADISR_vect)
+{
+    reti();
+};
+
 const HD44780_config lcd_config = {PORTD, PIN2_bm, PIN3_bm, PIN4_bm, PIN5_bm, PIN6_bm, PIN7_bm};
 
 HD44780 lcd(lcd_config);
 
+
 int main()
 {
-    gpio led(PORTD, PIN0_bm);
     led.set_direction(OUTPUT);
 
     gpio backlight(PORTD, PIN1_bm);
     backlight.set_direction(OUTPUT);
     backlight.on();
 
+    gpio button(PORTA, PIN2_bm);
+    button.set_direction(INPUT);
+    //button.set_mode(TOTEM_PULL_UP);
+    //button.set_invert(true);
+
+    PORTA.INTCTRL   = PORT_INT0LVL_HI_gc;
+    PORTA.INT0MASK  = PIN2_bm;
+    PORTA.PIN2CTRL |= PORT_ISC_RISING_gc | PORT_OPC_PULLUP_gc | PORT_INVEN_bm;
+    PMIC.CTRL = PMIC_HILVLEN_bm | PMIC_RREN_bm;
+
     PORTC.DIRSET = PIN4_bm | PIN5_bm | PIN6_bm | PIN7_bm;
     PORTC.OUTCLR = PIN4_bm | PIN5_bm | PIN6_bm | PIN7_bm;
 
@@ -34,15 +57,19 @@ int main()
     uart_ini();
     lcd.init();
 
+    sei();
+
     wellcome();
 
     for(;;)
     {
+        /*
         led.toggle();
         _delay_ms(500);
 
         led.toggle();
         _delay_ms(500);
+        */
     }
 }