ПРОСТЫЕ ЧАСЫ ATMEGA8 + TM1637 + DS3231

#include <EEPROM.h>
#include <DS3231.h>
#include <Wire.h>
#include <STM32_TM1637.h>
  DS3231 clock;
  RTCDateTime DateTime;
  STM32_TM1637 tm(PD2,PD3);// CLK, DIO 
  int timer;
  byte hour,minut,hh,mm,sett;
  bool w,ww,alarm;

  // PD0, PD1(2, 3) = RXD TXD
  // PC3(26) = SQW DS3231
  // PC2(25) = HOUR+
  // PC1(24) = MINUTE+
  // PC0(23) = SETTING
  // PC4(27) = SDA
  // PC5(28) = SCL
  // PD2, PD3(4, 5) = CLK DIO TM1637
  // PD6(12) = LED ALARM

void setup(){
   Wire.begin();
   clock.begin();
   tm.brig(7);
   clock.setOutput(DS3231_1HZ);
   PORTC |= (1 << 2)|(1 << 1)|(1 << 0); // INPUT_PULLUP PC0 PC1 PC2
   DDRB |= (1 << 5);
   hh = EEPROM.read(0);mm = EEPROM.read(1);alarm = EEPROM.read(2);
  }

void loop(){
  DateTime = clock.getDateTime();
  hour = DateTime.hour;
  minut = DateTime.minute;
  timer = hour*100 + minut;
  
 if(sett == 0) {tm.print_time(timer, ((PINC >> 3) & 1));}
 if(sett == 1) {tm.print_time(timer, 1);}
 if(sett == 2) {tm.print_time(hh*100+mm, 0);}

  if(((PINC >> 2) & 1) == LOW && sett == 1){ /////// BUTTON PC2 = HOUR+
    w=1; hour++; if(hour>23){hour=0;} delay(300);}
  if(((PINC >> 1) & 1) == LOW && sett == 1){ /////// BUTTON PC1 = MINUTE+
    w=1; minut++; if(minut>59){minut=1;} delay(300);}

  if(((PINC >> 2) & 1) == LOW && sett == 2){ /////// BUTTON ALARM PC2 = HOUR+
    ww=1; hh++; if(hh>23){hh=0;} delay(300);}
  if(((PINC >> 1) & 1) == LOW && sett == 2){ /////// BUTTON ALARM PC1 = MINUTE+
    ww=1; mm++; if(mm>59){mm=0;} delay(300);}

  if(((PINC >> 2) & 1) == LOW && sett == 0){ /////// BUTTON PC2 = alarm on
    alarm = 1; EEPROM.update(2,alarm);delay(300);}
  if(((PINC >> 1) & 1) == LOW && sett == 0){ /////// BUTTON PC1 = alarm off
    alarm = 0; EEPROM.update(2,alarm);delay(300);}  
    if(alarm == 1){PORTB |= (1 << 5);}else{PORTB &= ~(1 << 5);} 
     
  //// setting
  if(((PINC >> 0) & 1) == LOW){sett++;if(sett > 2){sett=0;}delay(300);}
   
 ////////// SET 
 if(w == 1){w=0; clock.setDateTime(2020, 8, 20, hour, minut, 0);}
 if(ww == 1){ww=0; EEPROM.update(0,hh);EEPROM.update(1,mm);}
 
 if((hh*100+mm == hour*100+minut) && alarm==1){tone(6,1500,150);}
 
 // delay(100);
  }