/*
 ###  simplest ever Arduino UNO digital clock  ###
 Time settings
 - Press on H increments the Hours
 - Press on M increments the Minutes and resets the seconds
*/

// initial Time display is 12:59:45 PM
int h=12;
int m=59;
int s=45;
int flag=1; //PM

// Time Set Buttons
int button1;
int button2;

// Pins definition for Time Set Buttons
int hs=A4;// pin A4 for Hours Setting
int ms=A5;// pin A5 for Minutes Setting

// Backlight Time Out 
const int Time_light=150;
int bl_TO=Time_light;// Backlight Time-Out
int bl=10; // Backlight pin
const int backlight=120; // no more then 7mA !!!

// For accurate Time reading, use Arduino Real Time Clock and not just delay()
static uint32_t last_time, now = 0; // RTC

#include <LiquidCrystal_I2C.h> 
// #include <BigNumbers_I2C.h>

LiquidCrystal_I2C lcd(0x27,16,2); // construct LCD object
// BigNumbers_I2C bigNum(&lcd);      // construct BigNumbers_I2C object, passing to it the name of our LCD object

byte x = 0;//x & y determines position of character on screen
byte y = 0;
byte i=0;

int M[3][4] = {{1, 2, 3, 4}, {6, 7, 8, 9}, {10, 11, 12, 13}};
int mS[4][4] = {{1, 0, 0, 0}, {0, 0, 1, 0}, {0, 1, 0, 0}, {0, 0, 0, 1}};
int STPn[] = {0, 0, 0, 0};
int mN = 0;

void setup() {
  // Serial.begin(9600);
 	// initialize the LCD
	lcd.init();
	lcd.backlight();
  lcd.setCursor(3,0);
 // bigNum.begin();     // set up BigNumbers
  lcd.clear();        // clear display

  pinMode(hs,INPUT_PULLUP);// avoid external Pullup resistors for Button 1
  pinMode(ms,INPUT_PULLUP);// and Button 2
  now=millis(); // read RTC initial value  

  for (int i=1; i<=13; i++) {
    pinMode(i, OUTPUT);
    digitalWrite(i, LOW);
  }
  for (int i=0; i<=4; i++) {
    for (int j=0; j<=4; j++) {
      pinMode(M[i][j], OUTPUT);
      digitalWrite(M[i][j], LOW);
    }
  }
}

void loop() {
  lcd.init();     // every second
// Update LCD Display - Print TIME in Hour, Min, Sec + AM/PM
 lcd.setCursor(0,0);
 lcd.print("Time ");
 if(h<10)lcd.print("0");// always 2 digits
 lcd.print(h);
 lcd.print(":");
 if(m<10)lcd.print("0");
 lcd.print(m);
 lcd.print(":");
 if(s<10)lcd.print("0");
 lcd.print(s);
 if(flag==0) lcd.print(" AM");
 if(flag==1) lcd.print(" PM");
 
 lcd.setCursor(0,1);// for Line 2
 lcd.print("Precision clock");

// improved replacement of delay(1000) 
// Much better accuracy, no more dependant of loop execution time
for ( int i=0 ;i<5 ;i++) {  // make 5 time 200ms loop, for faster Button response
  while ((now-last_time)<200) { //delay200ms
    now=millis();
  }
 // inner 200ms loop
 last_time=now; // prepare for next loop 

 // read Setting Buttons
 button1=digitalRead(hs);// Read Buttons
 button2=digitalRead(ms);
 
 // Hit any to activate Backlight 
 if(  ((button1==0)|(button2==0)) & (bl_TO==1)) {
   bl_TO=Time_light;
  analogWrite(bl,backlight);
  // wait until Button released
  while ((button1==0)|(button2==0)) {
   button1=digitalRead(hs);// Read Buttons
   button2=digitalRead(ms);
  }
 }
 else {
 // Process Button 1 or Button 2 when hit while Backlight on 
  if(button1==0){
   h=h+1;
   bl_TO=Time_light;
   analogWrite(bl,backlight);
  }
 if(button2==0){
  s=0;
  m=m+1;
  bl_TO=Time_light;
  analogWrite(bl,backlight);
  }

// Update display if time set button pressed
 if((button1==0)|(button2==0)) { 
  // Update LCD Display
  // Print TIME in Hour, Min, Sec + AM/PM
  lcd.setCursor(0,0);
  lcd.print("Time ");
  if(h<10)lcd.print("0");// always 2 digits
  lcd.print(h);
  lcd.print(":");
  if(m<10)lcd.print("0");
  lcd.print(m);
  lcd.print(":");
  if(s<10)lcd.print("0");
  lcd.print(s);

  if(flag==0) lcd.print(" AM");
  if(flag==1) lcd.print(" PM");
 
  lcd.setCursor(0,1);// for Line 2
  lcd.print("Precision clock");
 }
 } // end if else
}// end for

// outer 1000ms loop
s=s+1; //increment sec. counting    
    for (int y2y=0; y2y <=20; y2y++) {
Rotate(0, STPn[0]);  // mN =  Motor Number  - STPn[mN] = The last Step for THIS Motor
    }
// ---- manage seconds, minutes, hours am/pm overflow ----
 if(s==60){
  s=0;
  m=m+1;
      for (int y2y=0; y2y <=20; y2y++) {
  Rotate(1, STPn[1]);  // mN =  Motor Number  - STPn[mN] = The last Step for THIS Motor
      }
 }
 if(m==60) {
  m=0;
  h=h+1;
      for (int y2y=0; y2y <=20; y2y++) {
  Rotate(2, STPn[2]);  // mN =  Motor Number  - STPn[mN] = The last Step for THIS Motor
      }
 }
 if(h==13) {
  h=1;
  flag=flag+1;
  if(flag==2)flag=0;
 } 
}

void Rotate(int mN2, int STPn2) {
  for (int j=0; j<=3; j++) {
    digitalWrite(M[mN2][j], mS[STPn2][j]);
  }
  if (STPn[mN2] < 3) {
    STPn[mN2]++;
  } else {
    STPn[mN2] = 0;
  }
   delay(3);  // Stepper min Delay between Comands
}