Cycle between High and LOW signal every milliseconds for 6 seconds

Projects Programming
16

Here is something that you might find useful

const byte outPin = 3;
unsigned long currentTime;
unsigned long longPeriodStart;
unsigned long shortPeriodStart;
unsigned long longPeriod = 6000000;   //6 seconds in microseconds
unsigned long shortPeriod = 1000;     //1 millisecond in microseconds
boolean pulsing = true;

void setup()
{
  Serial.begin(115200);
  pinMode(outPin, OUTPUT);
  currentTime = micros();
  longPeriodStart = currentTime;
  shortPeriodStart = currentTime;
}

void loop()
{
  currentTime = micros();
  if (currentTime - longPeriodStart >= longPeriod)
  {
    Serial.println("toggle");
    pulsing = !pulsing;
    longPeriodStart = currentTime;
    shortPeriodStart = currentTime;
  }
  if (pulsing)
  {
    output();
  }
}

void output()
{
  if (currentTime - shortPeriodStart >= shortPeriod)
  {
    digitalWrite(outPin, !digitalRead(outPin));
    shortPeriodStart = currentTime;
  }
}

As written the code toggles between producing pulses for 6 seconds and not producing pulses for 6 seconds. To start producing pulses set the pulsing boolean to true for the required period, perhaps as a result of user input.