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Lesson 99: Real-Time Cloick DS3231 to build LCD and LED Clock

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Lesson 99: Real-Time Cloick DS3231 to build LCD and LED Clock

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Please download required files for this code

Part 13: Clock and Timers

This code is part of a lesson on building LED clock Arduino and DS3231 RTC clock module. We are using HT16K33 4 digit LED display to make this clock. This is code 99-4. Basic HT16K33 clock.


 /*
 * Lesson 99
 * file: DS3231_HT16K33_clock_display
 * Digital clock using DS3231 Real Time clock module and Arduino
 * Displays time on 4 digits seven segment dispaly HT16K33
 * Used DW3231 library and HT16K33 library below
 * watch video instruction:
 * 
 * video instruction  * https://youtu.be/LEQfzmO9Wm0
 *  * This code is part of Arduino Step by Step Course which starts here:  https://youtu.be/-6qSrDUA5a8
 *  
 * Written by Ahmad Shamshiri on Feb 07, 2021 in Ajax, Ontario, Canada
 * www.Robojax.com
 * 
  * 
 * This code is "AS IS" without warranty or liability. Free to be used as long as you keep this note intact.* 
 * This code has been download from Robojax.com
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
  
  DS3231: Real-Time Clock. Simple example
  Read more: www.jarzebski.pl/arduino/komponenty/zegar-czasu-rzeczywistego-rtc-ds3231.html
  GIT: https://github.com/jarzebski/Arduino-DS3231
  Web: http://www.jarzebski.pl
  (c) 2014 by Korneliusz Jarzebski

  HT16k33 library
//  AUTHOR: Rob Tillaart
// VERSION: 0.1.0
// PURPOSE: demo
//     URL: http://www.adafruit.com/products/1002
//     URL: https://github.com/RobTillaart/HT16K33
  
*/

#include <Wire.h>
#include <DS3231.h>

DS3231 clock;
RTCDateTime dt;

#include "HT16K33.h"
HT16K33  seg(0x70);//initialize the display with 0x70 I2C address

//watch video for settings details and demo https://youtu.be/XGsT-0P0gMU
bool showSecond = true;//show or hide seconds. set to false to not show
unsigned int secondDisplayEvery=5000;//show seconds every 10 seconds
unsigned int secondBlinkCount=6;//show 3 blinks of second 
unsigned int secondDisplayDuration =20000;//for how long seconds should be shown (in milliseonds)
bool showLeadingZero =true;
bool showSecondNoBlink=true;//just count senconds no blink



unsigned long rememberTime = millis();


void showSeconds1();
void showSeconds2();
void setup()
{
  Serial.begin(9600);

  // Initialize DS3231
  Serial.println("Robojax Digitla Clock");
  Serial.println("using DS3231 and HT16K33");  
  clock.begin();
  seg.begin();
  Wire.setClock(100000);

  seg.displayOn();

  seg.setDigits(4);
  seg.displayTest(1); 
   
  seg.displayOff(); 
  delay(50);
  seg.displayOn();  
  seg.brightness(10);//set brightness from 1-15     
  // Set sketch compiling time
  clock.setDateTime(__DATE__, __TIME__);
  
  // Manual (YYYY, MM, DD, HH, II, SS
   //clock.setDateTime(2021, 4, 13, 8, 01, 00);  
}

void loop()
{
  (showLeadingZero)? seg.setDigits(4) : seg.setDigits(3);

  //watch video for details
  dt = clock.getDateTime();
 
  printTime();//print time on serial monitor
  seg.displayTime(dt.hour,dt.minute);
  seg.displayColon(1);     
  delay(500);
  seg.displayColon(0);  
  delay(500); 

  (showSecondNoBlink)? showSeconds2() : showSeconds1();  
 
}//



/*
 * 
 * @brief shows seconds on HT16K33 display
 * with blinking
 * @param none
 * @return no return value
 * written Feb 06, 2021 by Ahmad Shamshiri
 * www.robojax.com
 */
void showSeconds1()
{
  int count = secondBlinkCount;
  if(showSecond){
      if(millis() - rememberTime   > secondDisplayEvery)
      {
          while(count>=0)
          {
            dt = clock.getDateTime();         
            count -=1;      
            seg.setDigits(2);    
            seg.displayInt(dt.second);     
            delay(500);
            seg.displayOff();  
            delay(500);  
            seg.displayOn();
            rememberTime = millis()  ;  
          }// while end    
      }//if
  }//if showSecond is true
}//showSecond() end

/*
 * 
 * @brief shows seconds on HT16K33 display
 * without blinking. 
 * @param none
 * @return no return value
 * written Feb 06, 2021 by Ahmad Shamshiri
 * www.robojax.com
 */
void showSeconds2()
{
  int count = secondDisplayDuration;

  if(showSecond){
      if(millis() - rememberTime   > secondDisplayEvery)
      {
          while(count>=0)
          {        
            dt = clock.getDateTime();         
            count -=50;      
            seg.setDigits(2);    
            seg.displayInt(dt.second);     
            delay(50);
            rememberTime = millis()  ;  
          }// while end    
      }//if
  }//if showSecond is true
}//showSeconds2() end

/*
 * 
 * @brief prints time on serial monitor
 * @param none
 * @return no return value
 * written Feb 06, 2021 by Ahmad Shamshiri
 * www.robojax.com
 */
void printTime()
{
  Serial.print("Raw data: ");
  Serial.print(dt.year);   Serial.print("-");
  Serial.print(dt.month);  Serial.print("-");
  Serial.print(dt.day);    Serial.print(" ");
  Serial.print(dt.hour);   Serial.print(":");
  Serial.print(dt.minute); Serial.print(":");
  Serial.print(dt.second); Serial.println("");
}//printTime() end
   

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