button with debounce and change of state with no delays DMJX

main.cpp

#include <Arduino.h>

int buttonPin = 2; 
int ledPin = 13;

int buttonState = HIGH;
int lastButtonState = LOW; 

int ledState = LOW;
bool blinkFast = true;

unsigned long fastBlinkInterval = 100;
unsigned long slowBlinkInterval = 600;

unsigned long elapsedTimeInMillis = 0; 
unsigned long lastBlinkTime = 0; 

unsigned long lastDebounceTime = 0;
unsigned long debounceDelay = 20;



void setup() {
  Serial.begin(9600);
  
  // put your setup code here, to run once:
  pinMode(buttonPin, INPUT_PULLUP);
  pinMode(ledPin, OUTPUT);

  while(!Serial) {
    ;
  }
  Serial.println("Hej HEJ!");
}

// logical operators:
// !=  NOT -> er det ikke det samme 
// == COMPARISON -> er det det samme 
// && og 
// || eller
// < mindre end
// støre 
// ++ = +1 
// -- 
// var = nyvar ASSIGNMENT
// += assignment + værdi  
// -= assignment - værdi
/*int mitTal = 4;
mitTal += 2;
mitTal = mitTal + 2;
*/

void loop() {
  // put your main code here, to run repeatedly:

  elapsedTimeInMillis = millis();


  int buttonReading = digitalRead(buttonPin);

  if(buttonReading != lastButtonState) {
    //buttonState = buttonReading;
    lastDebounceTime = elapsedTimeInMillis;
  }

  if( (elapsedTimeInMillis - lastDebounceTime) > debounceDelay ) {
    // er der gået mere end 2 millissekunder siden sidste ændring 
    if(buttonReading != buttonState) {
      buttonState = buttonReading;
      if(buttonState) {
        blinkFast = !blinkFast;
      }
      Serial.print("buttonState: ");
      Serial.print(buttonState);
      Serial.print(" blinkFast: ");
      Serial.println(blinkFast);
    }
  }

  lastButtonState = buttonReading;

  if(blinkFast) {
    // blink hurtigt 
    
    if((elapsedTimeInMillis - lastBlinkTime) > fastBlinkInterval ) {
      ledState = !ledState;
      lastBlinkTime =  elapsedTimeInMillis;
    }
    // gem interval mellem blink 
    // hvis tid der er gået siden led sidst 
    // tændte eller slukkede er større end interval
    // så tænd eller sluk 

  } else {
    // blink langsomt
    if((elapsedTimeInMillis - lastBlinkTime) > slowBlinkInterval  ) {
      ledState = !ledState;
      lastBlinkTime =  elapsedTimeInMillis;
    }
  }

  digitalWrite(ledPin, ledState);

}