#include <LiquidCrystal.h>
#include <Keypad.h>

LiquidCrystal lcd(12, 11, 10, 9, 8, 7);


const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char keys[ROWS][COLS] = {
  { 1, 2, 3, '>' },
  { 4, 5, 6, '<' },
  { 7, 8, 9, 'E' },
  { '0', 'D', 'S', 'M' }
};

uint8_t colPins[COLS] = { A3, A2, A1, A0 }; // Pins connected to C1, C2, C3, C4
uint8_t rowPins[ROWS] = { 5, 4,3, 2 }; // Pins connected to R1, R2, R3, R4

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);



int count;
bool run=false;



void setup() {                 // set up everything
pinMode(6, OUTPUT);            // Set the pin to be OUTPUT
pinMode(13,OUTPUT);
count=0;
TCCR1A = 0;                 // Reset entire TCCR1A to 0 
TCCR1B = 0;                 // Reset entire TCCR1B to 0
TIMSK1 = B00000110; //Set OCIE1A to 1 so we enable compare match A 
OCR1A = 15466 -60;          // set compare register A  to 15466 - interrupt latency correction 
OCR1B = 7733;               // set compare register B to 500 to give vpulse width 2000us
digitalWrite(6,false);          // make thw v pulse potput false (D6)
digitalWrite(13,false); 
lcd.begin(16,2);               // initialise the lcd to 20 char wide and 4 rows (for simulation but ok for 16*2 display also)
lcd.setCursor(0, 0);           // set lcd cursor to start of display lin 0
lcd.print("  Brake Tester");  // print first line of welcome message on display
lcd.setCursor(0,1);            // set lcd cursor to start of display line 1
lcd.print(" Pulse Generator"); // print second line of welcome message on display  
//run = true;

delay (2000);                  // wait 4 seconds displaying welcome message
  
lcd.clear();                   // clear the display
}


void loop()
{
 char key = keypad.getKey();
  if (key!= 0)
  {
    if (key == '>') 
    {
      run=true;
      TCCR1B = B00000001;
 
    }

    if (key == '<') 
    {
      run=false;
      TCCR1B = B00000000;
    }
  }

  if (run==true)
  {
    lcd.setCursor(0,0);
    lcd.print("Rolling Road Sim");
    lcd.setCursor(0,1);
    lcd.print(" Press < to Stop");
  }
  else
  {
    lcd.setCursor(0,0);
    lcd.print("Rolling Road Sim");
    lcd.setCursor(0,1);
    lcd.print(" Press > to Run ");
  }



 
}





ISR(TIMER1_COMPA_vect)          // timer 1 comparator A interrupt vector 
{                               // come here every time counter = comparison register A
  TCNT1  = 0;                   // set the timer back to 0 so it resets for next interrupt
  digitalWrite(6,true);        // then write new state to the pulse output on D6 (high to start v pulse)
  if (count>=400) digitalWrite(13,false);
}


ISR(TIMER1_COMPB_vect)          // timer 1 comparator B interrupt vector 
{                               // come here every time counter = comparison register B
  digitalWrite(6,false);         // write new state to the pulse output on D6 (low to end vpulse)
  count ++;
  if (count>=4297)
  {
    count=0;
    digitalWrite(13,true);
  }



}