Big Clock

//  * Korekce času pomocí tlačítka na pinu 9. pullUp zapnut

#include <Wire.h> // Enable this line if using Arduino Uno, Mega, etc.
#include <Adafruit_GFX.h>
#include "Adafruit_LEDBackpack.h"
#define DS3231_I2C_ADDRESS 0x68

const int ledPin =  13;      // číslo pinu LED
int buttonState = 0;    // proměnná pro čtení stavu tlačítka
Adafruit_7segment matrix = Adafruit_7segment();

byte decToBcd(byte val){
return ( (val/10*16) + (val%10) );
}

byte bcdToDec(byte val){
return ( (val/16*10) + (val%16) );
}

////////////////// korekce času /////////////////////////
void resetTime(){
    pinMode(9,INPUT_PULLUP);          // nastavení vstupu a pullup odporu
    buttonState = digitalRead(9);
    
    // zkontroluje, zda-li je tlačítko stlačené.
    if (buttonState == LOW) {digitalWrite(ledPin, HIGH);}
    else {digitalWrite(ledPin, LOW);}
    
    byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
    getDateDs3231(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year);
    //korekce sekund zpět              
    if (buttonState == LOW && second<30) {setDS3231time(0, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year);}
    //korekce sekund vpřed               
    if (buttonState == LOW && second>30) {setDS3231time(59, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year);} 
    }


    

void setup() {
  Wire.begin();
  matrix.begin(0x70);
  // set the initial time here:
  // DS3231 seconds, minutes, hours, day, date, month, year
  // setDS3231time(0,59,13,5,28,9,17);
  pinMode(ledpin, OUTPUT);
}

void loop() {
    displayTime(); // display the real-time clock data 
    displayTemp(); // display the temperature
    // blink dot
    for (uint16_t counter = 0; counter < 5; counter++) {
    matrix.writeDigitRaw(2,0x4);
    matrix.writeDisplay();
    delay(500);
    matrix.writeDigitRaw(2,0x8);
    matrix.writeDisplay();
    delay(500);
    }
    resetTime();   // reset sekund pokud je zmačknute tlačitko
    displayTime(); // display the real-time clock data 
    displayDate(); // display the date 
    
  }

void displayTime(){
 for (uint16_t counter = 0; counter < 10; counter++) {
  byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
  getDateDs3231(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year);
    matrix.writeDigitNum(0, (hour / 10), false);
    matrix.writeDigitNum(1, (hour % 10), false);
    matrix.drawColon(true);
    matrix.writeDigitNum(3, (minute / 10), false);
    matrix.writeDigitNum(4,(minute % 10), false);
    matrix.writeDisplay();
    delay(500);
    matrix.drawColon(false);
    matrix.writeDisplay();
    delay(500);
    }    
  }

void displayDate(){
 for (uint16_t counter = 0; counter < 10; counter++) {
  byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
  getDateDs3231(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year);
    matrix.writeDigitNum(0, (dayOfMonth / 10), false);
    matrix.writeDigitNum(1, (dayOfMonth % 10), false);
    matrix.drawColon(false);
    matrix.writeDigitNum(3, (month / 10), false);
    matrix.writeDigitNum(4,(month % 10), false);
    matrix.writeDisplay();
    delay(500);
    }    
  }

void displayTemp(){
  byte temp = get3231Temp();
  matrix.clear(); 
  matrix.writeDigitRaw(4,57); // 57 = "C"
  matrix.writeDigitRaw(3,99); // 57 = "C"
  matrix.writeDigitNum(0, (temp/10), false); // position 0, value 1, show decimal)
  matrix.writeDigitNum(1,( temp % 10), false); // position 1, value 9, show decimal)
  matrix.writeDisplay();
 }

void setDS3231time(byte second, byte minute, byte hour, byte dayOfWeek, byte dayOfMonth, byte month, byte year){
    // sets time and date data to DS3231
    Wire.beginTransmission(DS3231_I2C_ADDRESS);
    Wire.write(0); // set next input to start at the seconds register
    Wire.write(decToBcd(second)); // set seconds
    Wire.write(decToBcd(minute)); // set minutes
    Wire.write(decToBcd(hour)); // set hours
    Wire.write(decToBcd(dayOfWeek)); // set day of week (1=Sunday, 7=Saturday)
    Wire.write(decToBcd(dayOfMonth)); // set date (1 to 31)
    Wire.write(decToBcd(month)); // set month
    Wire.write(decToBcd(year)); // set year (0 to 99)
    Wire.endTransmission();
   }

void getDateDs3231(byte *second,
    byte *minute,
    byte *hour,
    byte *dayOfWeek,
    byte *dayOfMonth,
    byte *month,
    byte *year)
{
Wire.beginTransmission(DS3231_I2C_ADDRESS);
Wire.write(0);
Wire.endTransmission();

Wire.requestFrom(DS3231_I2C_ADDRESS, 7);

*second = bcdToDec(Wire.read() & 0x7f);
*minute = bcdToDec(Wire.read());
*hour = bcdToDec(Wire.read() & 0x3f);
*dayOfWeek = bcdToDec(Wire.read());
*dayOfMonth = bcdToDec(Wire.read());
*month = bcdToDec(Wire.read());
*year = bcdToDec(Wire.read());
}

  float get3231Temp(){
  byte tMSB, tLSB;
  float temp3231;

Wire.beginTransmission(0x68);
Wire.write(0x11);
Wire.endTransmission();
Wire.requestFrom(0x68, 2);

  if(Wire.available()) {
    tMSB = Wire.read(); //2's complement int portion
    tLSB = Wire.read(); //fraction portion
    temp3231 = (tMSB & B01111111); //do 2's math on Tmsb
    temp3231 += ( (tLSB >> 6) * 0.25 ); //only care about bits 7 & 8
  }
  else {
    //oh noes, no data!
  }

  return temp3231;
}