(solved)could use help with POV-clock code (trouble with even starting correct timing......)

int const ledPin = 13;
int half_revolutions = 0;
int state = LOW;
int rpm = 0;

unsigned long lastmillis = 0;

void setup()
{
  Serial.begin(9600);
  attachInterrupt(0, rpm_fan, FALLING);
  pinMode (ledPin, OUTPUT);
  }






void loop(){


if (millis() - lastmillis == 1000){ //Uptade every one second, this will be equal to reading frecuency (Hz).

detachInterrupt(0);//Disable interrupt when calculating

rpm = half_revolutions * 60; // Convert frecuency to RPM, note: this works for one interruption per full rotation. For two interrups per full rotation use half_revolutions * 30.

Serial.print("RPM =\t"); //print the word "RPM" and tab.
Serial.print(rpm); // print the rpm value. Serial.print("\t Hz=\t"); //print the word "Hz".

half_revolutions = 0; // Restart the RPM counter
lastmillis = millis(); // Uptade lasmillis
attachInterrupt(0, rpm_fan, FALLING); //enable interrupt
}
}

// this code will be executed every time the interrupt 0 (pin2) gets low.

void rpm_fan()

{
  digitalWrite (ledPin, state);
  (state = !state);
  half_revolutions++;
}

#include <Servo.h>
Servo esc;
int throttlepin = 0;   //analog input pin for potentiometer (as voltage divider/reference)
int inPin = 2;         // the number of the input pin
int outPin = 13;       // the number of the output pin

int state = HIGH;      // the current state of the output pin
int reading;           // the current reading from the input pin
int previous = LOW;    // the previous reading from the input pin
// the follow variables are long's because the time, measured in miliseconds,
// will quickly become a bigger number than can be stored in an int.
long time = 0;         // the last time the output pin was toggled
long previousmillis = 0;
long starttime;
long elapsedtime;



void setup()
{
  esc.attach(9);
  pinMode(inPin, INPUT);
  pinMode(outPin, OUTPUT);
}

void loop()
{
  int throttle = analogRead(throttlepin);
  throttle = map(throttle, 0, 1023, 0, 179);
  esc.write(throttle);

  reading = digitalRead(inPin);
if (reading == HIGH && previous == LOW)
{
if (state == HIGH)
starttime = millis();
}
previous = reading;
elapsedtime = millis () - starttime;
if (elapsedtime ==0 && elapsedtime <=4.17)           //turn led on between 0-4.17ms
{
  digitalWrite (outPin, HIGH);
  }
  if (elapsedtime >=5)                               //turn led off at 5ms
  {
  digitalWrite (outPin, LOW);
  }
  }

attachInterrupt(digitalPinToInterrupt(pin), ISR, mode);

int pin = 13;
volatile int state = LOW;

void setup() {
    pinMode(pin, OUTPUT);
    attachInterrupt(digitalPinToInterrupt(2), blink, FALLING);
}

void loop()
{
//timing calculation here?
}

void blink() {
  digitalWrite(pin, state);
    state = !state;
}

int const outpin = 13;
int state = LOW;
int reading;
int previous = LOW;
volatile long time = 0;
volatile long previousmillis = 0;
volatile long starttime;
volatile long elapsedtime;

void setup() {
    pinMode(outpin, OUTPUT);
    attachInterrupt(digitalPinToInterrupt(2), blink, CHANGE);
}

void loop()
{
  reading = state;
if (reading == HIGH && previous == LOW)
{
if (state == HIGH)
starttime = millis();
}
previous = reading;
elapsedtime = millis () - starttime;
if (elapsedtime ==0 && elapsedtime <=4.17)           //turn led on between 0-4.17ms
{
  digitalWrite (outpin, HIGH);
  }
  if (elapsedtime >=5)                               //turn led off at 5ms
  {
  digitalWrite (outpin, LOW);
  }

  }


void blink() {
  digitalWrite(outpin, state);
    state = !state;
    Serial.println(elapsedtime);
}