#include <TimerOne.h>

const int pinData = 6;
const int pinStatus = 7;

void setup(void)
{
  pinMode(pinData, OUTPUT);
  //Timer1.initialize(60);
  //Timer1.attachInterrupt(clockCycle);

  Timer1.initialize(1100/2);
  Timer1.attachInterrupt(clockCycle);
  Timer1.stop();
    
  pinMode(pinStatus, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(pinStatus), statusCycle, CHANGE);
  
  Serial.begin(9600);
}

volatile long lastChange = 0;
volatile long lastStart = 0;
volatile int x = 0;
volatile int dataWord = 0;
volatile int dataState = 0;
volatile int dataDelay = 0;
volatile int clkState = LOW;

void statusCycle() {
  long timeNow = millis();
  long changeDiff = timeNow - lastChange;
  lastChange = timeNow;
  if (changeDiff >= 10) {
    lastStart = timeNow;

    dataWord = (' ' + x);
    dataState = 8;
    dataDelay = 0;
    x = (x + 1) % 100; 
    clkState = HIGH;
    Timer1.start();
  }
  if (timeNow - lastStart >= 7 && changeDiff >= 2) {
    //dataWord = 0b1000000011 | (('A' + x) << 2);
    
  }
}

void clockCycle(void)
{
  if (clkState == LOW) {
    clkState = HIGH;
    //digitalWrite(pinData, (dataState > 0) ? LOW : HIGH);
  } else {
    clkState = LOW;
    if (dataDelay > 0) {
      dataDelay--;
    } else if (dataState > 0) {
      int bitToSend = (dataWord >> (dataState - 1)) & 1;
      //digitalWrite(pinData, bitToSend ? LOW : HIGH);
      dataState--;
      if (dataState <= 0) {
        Timer1.stop();
      }
    } else {
      //digitalWrite(pinData, HIGH);
    }
  }
  if (dataDelay <= 0 && dataState > 0)
    digitalWrite(pinData, clkState);
    else
    digitalWrite(pinData, HIGH);
}

void loop(void)
{
  delay(500);
  
  /*noInterrupts();
  dataWord = 0b1000000011 | (('A' + x) << 2);
  dataState = 16;
  x = (x + 1) % 30;
  interrupts();*/
}