/*
  ============================
   Selfmade For-Loop III
  ============================

   This is an example of a "selfmade" for-loop
   which is usually required where a a non-blocking
   loop is required e.g. to blink an LED

   This is an example of a non-blocking millis() function replacing delay() 
   to blink a LED and counting a variable in given time intervals 

   First Edition 2023-04-02
   ec2021

   Simulation: https://wokwi.com/projects/360905127753897985
   Discussion: https://forum.arduino.cc/t/millis-instead-of-delay-and-loop-instead-of-for-loop/1110044

   Changed 2023-07-26

*/

constexpr byte LEDPin = 13;

void setup() {
   Serial.begin(115200);
   pinMode(LEDPin, OUTPUT);
}

unsigned long lastChange = 0;    // Variable to store the time in ms when ledState was changed 
unsigned long delayTime  = 300;  // Delay in [ms] when then next change shall take place 
unsigned long lastCount  = 0;
unsigned long delayCount = 500;

boolean firstBlink       = true;  // Added firstBlink and firstCount to make sure
boolean firstCount       = true;  // that the millis()-if-clauses are already entered 
                                  // in the first loop()

int i = 0;
int iMax = 9;

void loop() {

  if (millis()-lastChange >= delayTime || firstBlink){ 
     lastChange = millis();               
     boolean ledState = digitalRead(LEDPin);
     digitalWrite(LEDPin, !ledState); 
     firstBlink = false;
   }

  if (millis()-lastCount >= delayCount || firstCount){ 
     lastCount = millis();
     firstCount = false;
     if (i <= iMax) {                                                            
         Serial.print(i);
         Serial.print("\t"); // prints tabs
         i++;
      } else { 
         Serial.println();
         i = 0;
      }
   }
}