arduino digital clock

digital clock easy to build

rtc: https://www.laskakit.cz/arduino-rtc-hodiny-realneho-casu-ds3231-at24c32/

code:

#include <Wire.h>

#include <RTClib.h>

#include <TM1637Display.h>

#define CLK 2

#define DIO 3

bool alarmDone = false;

RTC_DS3231 rtc;

TM1637Display display(CLK, DIO);

void setup() {

pinMode(11, OUTPUT);

pinMode(4, INPUT_PULLUP);

Wire.begin();

rtc.begin();

display.setBrightness(0x0f); // Jas 0-15

// time set

//rtc.adjust(DateTime(2025, 6, 11, 16, 29, 0)); // 11. 6. 2025 14:30:00

}

void loop() {

if (digitalRead(4) == HIGH) {

display.clear();

} else {

DateTime now = rtc.now();

int hours = now.hour();

int minutes = now.minute();

bool noc = (hours >= 20 || hours < 6);

if (noc) {

display.setBrightness(1); //night brightnes

} else {

display.setBrightness(15); //day brightnes

}

display.showNumberDecEx(hours * 100 + minutes, 0b11100000, true);

delay(100);

if (hours == 7 && minutes == 0) {

analogWrite(11, 250);

delay(70);

analogWrite(11, 0);

delay(100);