Royal University of Phnom Penh

Faculty of Engineering

Dep. of Telecommunication and Electronic Engineering

Project Title: Stereo Audio Amplifier

Group member:

Ly Seyha, Tann Thona, Chhoy Noreath, Nop Da, Simpich Dany

Advisor: Dr. Thap Tharoeun

First Generation, Year 3rd Semester II

2017

I. Introduction

This is a stereo audio amplifier module using the KA2209 IC, which is equivalent to the TDA2822. It will operate well from 3 – 12v DC and will work from a battery since the quiescent current drain is low. It requires no heat sink for normal use. The input and output are both ground referenced. Maximum output will be obtained with a 12v power supply and 8-ohm speaker, however it is particularly suitable for driving headphones from a supply as low as 3V.

II. Specifications of KA2209

• D.C. input: 5 – 12 V at 200 – 500 mA max.
• Power output: - > 1-Watt max. 4-8 ohms, 12V DC
• > 500 mW, 32-ohm, 12V
• > 500 mW, 4-ohm, 6V
• Freq. Resp.: ~ 40 Hz to 200 kHz, 8-ohm, G=10
• < 20 Hz to > 50 kHz, 32 ohms
• THD: < 1 % @ 750 mW, 4-8Ω, 12V
• < 0.2 % @ 250 mW, 4-8Ω, 12V
• Sensitivity: < 300 mV, G = 20 dB

Figure 1. KA2209 IC

III. Assembly Instructions

• The electrolytic capacitors are polarized, they have a + or - marked on them and they must be inserted correctly into the PCB.
• The IC and socket have a notch at one end, which is marked on the PC board overlay. If there is no notch on the IC, there will be a dot next to pin 1, which is the same end.
• Solder the socket in place first before installing the IC itself, then resistors, capacitors, and PCB pins. Leave the potentiometer until last. We have also provided input attenuation via the potentiometer which can be used as a volume control. This will keep the signal to noise ratio as high as possible. Extra gain provided by the amplifier will reduce the S/N ratio by a similar amount, since the input noise figure is constant.

IV. Testing

Check the voltage and polarity before connecting the battery or power supply. If it does not work, recheck all component positions and polarity. Check all solder joints, and all external wiring. The IC itself is quite robust, and there is very little else to go wrong. Remember when testing, it will not produce full output for more than a short duration because of limited heat dissipation. We found it easily exceeded the manufacturers specifications however.

IV. Circuit Description

• R1, R2 and R3, R4 are the feedback resistors. 
• C1 provides power supply decoupling.
• C2, C3 are the output coupling capacitors.
• C4, R1 and C5, R2 block DC in the feedback circuit from the inverting inputs.
• C6, R3 and C7, R4 act as Zobel networks providing a high frequency load to maintain stability at frequencies where loud speaker inductive reactance may become excessive.
• C8 and C9 are the input coupling capacitors, which block any DC that might be present on the inputs.
• The pot provides adjustable input level attenuation.

Figure 2. Stereo Audio Circuit with KA2209 IC

V. Components Requirement

VI. Reference

Quasar Electronics Limited

PO Box 6935

Bishops Stortford

CM23 4WP

UNITED KINGDOM 

Website:    http://www.quasarelectronics.com/3087.htm

Photos

Date: 26 October 2017

Location: Royal University of Phnom Penh

7 Segment One Digit Display

1. Objective

2. Requirement

• Arduino
• USB Cable
• 7 Segment 1 Digit (Cathode Type)
• Resistor 220 or 330 Ohm
• Electronic Wire

3. Building

Figure 1: 7 Segment 1 Digit Connection

4. Coding

  // 22 October 2017

 
int PIN_A = 1;
int PIN_B = 2;
int PIN_C = 3;
int PIN_D = 4;
int PIN_E = 5;
int PIN_F = 6;
int PIN_G = 7;
int i = 0;
int j = 0;

int Arduino_Pins[7] = {PIN_A, PIN_B, PIN_C, PIN_D, PIN_E, PIN_F, PIN_G};   // an array of pin numbers to which LEDs
int Segment_Pins[10][7] = {{0,1,1,1,1,1,1}, // 0
                           {0,0,0,0,1,1,0}, // 1
                           {1,0,1,1,0,1,1}, // 2
                           {1,0,0,1,1,1,1}, // 3
                           {1,1,0,0,1,1,0}, // 4
                           {1,1,0,1,1,0,1}, // 5
                           {1,1,1,1,1,0,1}, // 6
                           {0,0,0,0,1,1,1}, // 7
                           {1,1,1,1,1,1,1}, // 8
                           {1,1,0,1,1,1,1}, // 9
                           }; 

void setup()  {
  // Configure Digital I/O
  pinMode(PIN_A, OUTPUT);
  pinMode(PIN_B, OUTPUT);
  pinMode(PIN_C, OUTPUT);
  pinMode(PIN_D, OUTPUT);
  pinMode(PIN_E, OUTPUT);
  pinMode(PIN_F, OUTPUT);
  pinMode(PIN_G, OUTPUT);
}

void loop() {

  for(i=0;i<10;i++) 
  {
    for(j=0;j<7;j++)  
    {
      digitalWrite(Arduino_Pins[j],Segment_Pins[i][j]);
    }
    delay(500);

    if(i==9)
    {           
      i = 0;      
    }
  }
}       
 

5. Result

Send Message Encrypt and Decrypt in Arduino

1. Objective

2. Requirement

• Arduino UNO (x2)
• USB Cable
• Button
• Electronic Wire

3. Building

Figure 1: Serial Communication Encrypt and Decrypt

4. Coding

      
char Ref[94] = {'0','1','2','3','4','5','6','7','8','9',
                'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
                'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z',
                '`','~','!','@','#','$','%','^','&','*','(',')','-','_','+','=','[',']','{','}','|',';',':','"','<','>',
                '/','?','.',',','\'','\\'};

int Encrypt[94] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,
                   36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,
                   69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93};

int button = 13;
String msg = "RUPP_MY002_L1_ON";
String a = "3";

void setup() {
  Serial.begin(9600);
  pinMode(button,INPUT_PULLUP);
}

void encryption(String str) {

  int msgLength = 0;
  int RefLength = 0;
  String dataEncrypt[20];

  //Serial.println(str);
  RefLength = sizeof(Ref);
  msgLength = str.length();

  // Encrypt
  for(int i=0;i<msgLength;i++) {
    for(int j=0;j<RefLength;j++) {
      if(msg[i]==Ref[j]) {
        dataEncrypt[i] = String(Encrypt[j]);
      }
    }
    Serial.print(dataEncrypt[i]);
    delay(30);
  }
}

void loop() {
  if(digitalRead(button)==0) {
    encryption(msg);
  }
}
 

#define Ref '_'
char Index[94] = {'0','1','2','3','4','5','6','7','8','9',
                'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
                'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z',
                '`','~','!','@','#','$','%','^','&','*','(',')','-','_','+','=','[',']','{','}','|',';',':','"','<','>',
                '/','?','.',',','\'','\\'};

int Encrypt[94] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,
                   36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,
                   69,70,71,72,73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93};

String msg[20];
String data[20];
String dataDecrypt;

int button = 13;
int i = 0;

void setup() {
  pinMode(button,INPUT_PULLUP);
  Serial.begin(9600);
  Serial.setTimeout(3);
}

void AnalyseMsg(String msg) {
  
  int msgLength = 0;      // Total of Message length
  int cnt = 0;            // Count Reference number
  int refLocate[10] = {0};  // Location of the Reference in the message
  int x = 0;              // Variable for helping arrange the msg
  int y = 0;              // Variable for helping arrange the msg
  msgLength = msg.length() - 1;

  for(int i=0;i<msgLength+1;i++) {
    if(Ref == msg[i]) {
      cnt++;
      refLocate[cnt] = i;
    }
  }
  //Serial.println(cnt); 
  refLocate[cnt+1] = msgLength;
  for(int j=0;j<cnt+1;j++) {
    if(refLocate[j+1] == msgLength) {
      y = 1;
    }
    for(int i=refLocate[j]+x;i<refLocate[j+1]+y;i++) {
      data[j] += msg[i];
    }
    Serial.println(data[j]);
    x = 1;
  }
  // Clear data
  for(int i=0;i<cnt+2;i++) {
    data[i] = "";
  }
}

void decryption() {
  for(int j=0;j<i;j++) {
    dataDecrypt += Index[msg[j].toInt()];
  }
  //Serial.println(dataDecrypt);
  AnalyseMsg(dataDecrypt);
  dataDecrypt = "";
  i = 0;
}

void Readmsg() {
  if(Serial.available()) {
    msg[i] = Serial.readString();
    //Serial.println(msg[i]);   
    i++;
  }
}

void loop() {
  Readmsg();
  if(digitalRead(button) == 0) {
    decryption();
    delay(200);
  }
}
 

5. Result

Figure 2: Result Sending Message with Encrypt and Decrypt in Proteus Simulation.

Send Message with Arduino Serial Communication

1. Objective

2. Component Requirement

• Arduino Uno (x2)
• USB Cable
• Button
• Electronic Wire

3.  Building

Figure 1: Arduino Serial Communication Connected

4. Coding

// Code by Tann Thona, 20 November 2017

 
int button = 13;
String msg="RUPP_MY002_L1_ON";

void setup() {
  // put your setup code here, to run once:
  pinMode(button,INPUT_PULLUP);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(digitalRead(button)==0)
  {
    Serial.print(msg);
    delay(100);
  }
  else
  {
    Serial.write('0');
    delay(100);
  }
}       
 

// Code by Tann Thona, 20 November 2017

#define Ref '_'
String rmsg;
int msglength=0;
int cnt=0;
int Reflocated[10]={0};
String data [20];
int x,y=0;
void setup() {
  // put your setup code here, to run once:
  Serial.setTimeout(30);
  Serial.begin(9600);
}
void loop() 
{
  msglength=0;
  cnt=0;
  Reflocated[10]={0};
  data [20];
  x = 0;
  y = 0;      
  // put your main code here, to run repeatedly:
  if(Serial.available())
  {
    rmsg = Serial.readString(); 
  msglength=rmsg.length()-1;
  for(int i=0;i<msglength+1;i++)
  {
    if(Ref ==rmsg[i]){
      cnt++;
      Reflocated[cnt]=i;
    }
  }
    Reflocated[cnt+1]=msglength;   
      for(int j=0;j<cnt+1;j++){
      if(Reflocated[j+1]==msglength){
        y=1;
      }
      for(int i=Reflocated[j]+x;i<Reflocated[j+1]+y;i++){
        data[j]+= rmsg[i];
      }
      Serial.println(data[j]);      
      Serial.println("---------------------------");
      data[j] = ' ';
      x=1;
    }
  }
}       
 

5. Resulte

Figure 2: Result Send Message in Arduino Use VIRTUAL TERMINAL in Proteus.

•  If we don't push button transmitter send message "0" and receiver also receive message "0" too.
• when we push button, transmitter send message “RUPP_MY002_L1_ON" to receiver then receiver separate in world readable RUPP MY002 L1 ON.

Transmit Data from One Arduino to Three Arduino

1. Objective

2. Requirement

• Arduino Uno (x4)
• USB Cable
• Resistor (220ohm or 330ohm)
• Button
• LED
• Electronic Wire

3. Circuit Connection

Figure 1. Circuit connection arduino serial communication

 4. Coding

// Code by Tann Thona 24 April 2017

int button1 = 13;
int button2 = 12;
int button3 = 11;
char inByte1 = '1';
char inByte2 = '2';
char inByte3 = '3';

void setup() {
  // put your setup code here, to run once:
  pinMode(button1,INPUT_PULLUP);
  pinMode(button2,INPUT_PULLUP);
  pinMode(button3,INPUT_PULLUP);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(digitalRead(button1)==0)
  {
    Serial.write(inByte1);
    delay(100);
  }
  else if(digitalRead(button2)==0)
  {
    Serial.write(inByte2);
    delay(100);
  }
  if(digitalRead(button3)==0)
  {
    Serial.write(inByte3);
    delay(100);
  }
  else
  {
    Serial.write('0');
    delay(100);
  }

}
 

// Code by Tann Thona 24 April 2017

int led1 = 13;
char inByte1 = '1';

void setup() {
  // put your setup code here, to run once:
  pinMode(led1,OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(Serial.available())
  {
   inByte1 = Serial.read();
   if(inByte1 == '1')
   {
    digitalWrite(led1,1);
   }
    else
    {
    digitalWrite(led1,0);
    }
  }

}

// Code by Tann Thona 24 April 2017

int led2 = 13;
char inByte2 = '2';

void setup() {
  // put your setup code here, to run once:
  pinMode(led2,OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(Serial.available())
  {
   inByte2 = Serial.read();
   if(inByte2 == '2')
   {
    digitalWrite(led2,1);
   }
    else
    {
    digitalWrite(led2,0);
    }
  }

} 

// Code by Tann Thona 24 April 2017

int led3 = 13;
char inByte3 = '3';

void setup() {
  // put your setup code here, to run once:
  pinMode(led3,OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(Serial.available())
  {
   inByte3 = Serial.read();
   if(inByte3 == '3')
   {
    digitalWrite(led3,1);
   }
    else
    {
    digitalWrite(led3,0);
    }
  }

}

5. Result

• Push button1 arduino transmitter tansmit number 1, LED's receiver 1 bright.
• Push button 2 arduino transmitter tansmit number 2, LED's receiver 2 bright.
• Push button 3 arduino transmitter tansmit number 3, LED's receiver 3 bright.

Serial Communication Between Two Arduino

1. Objective

2. Requirement

• Arduino Uno x2
• USB Cable x2
• Breadboard
• LED
• Resistor (220Ohm or 330Ohm)
• Button
• Electronic Wire

3. Build Circuit Serial Communication

Fig1.1. Serial communication between two Arduino

// Code by Tann Thona (24/04/2017)

// Transmitter Coder
int button = 13;
char inByte = '1';

void setup() {
  // put your setup code here, to run once:
  pinMode(button,INPUT_PULLUP);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(digitalRead(button)==0)
  {
    Serial.write(inByte);
    delay(100);
  }
  else
  {
    Serial.write('0');
    delay(100);
  }
}

// Code by Tann Thona (24/04/2017)

// Reciever Coder
int led = 13;
char inByte = '1';

void setup() {
  // put your setup code here, to run once:
  pinMode(led,OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(Serial.available())
  {
   inByte = Serial.read();
   if(inByte == '1')
   {
    digitalWrite(led,1);
   }
    else
    {
    digitalWrite(led,0);
    }
  }

}
 

Analog Read Control LED Light

1. Objective

2. Electronic Requirement

• Arduino Uno
• USB Cable
• Breadboard
• LED (or RGB)
• POT-HG (Variable Resistor)
• Resistor 330Ohm or 220Ohm (Digital pin --> Resistor --> LED)
• Electronic Wire

 3. Build Circuit

Fig1.1 Analog read to control LED lights.

// Coding by Tann Thona (26/03/2017), Adviser: Chann Tola  

float x=0;
float y=0;
int t =300;
void setup() 
{
pinMode(13,OUTPUT);
pinMode(1,OUTPUT);
pinMode(2,OUTPUT);
pinMode(3,OUTPUT);
//pinMode(10,OUTPUT);
}
void loop() 
{
  y = analogRead(A0);
  x=(5*y)/1023;
  if(x>3)
  {
    digitalWrite(13,HIGH);
  }
  else
  {
  digitalWrite(13,LOW);
  }

// LED Three color (RGB)

  digitalWrite(1,HIGH);
  digitalWrite(2,LOW);
  digitalWrite(3,LOW);
  delay(t);
//-------------------------
  digitalWrite(1,LOW);
  digitalWrite(2,HIGH);
  digitalWrite(3,LOW);
  delay(t);
//-------------------------
  digitalWrite(1,LOW);
  digitalWrite(2,LOW);
  digitalWrite(3,HIGH);
  delay(t);
//-------------------------
}       
 

4. Result

LCD 16x2 Display Automatic Scroll Letter

1. Objective

2. Electronic Requirement

• Arduino Uno
• USB Cable
• Breadboard
• LMO16L (LCD 16x2)
• Potentiometer (POT-HG Variable Resistor)
• Resistor (220Ohm)
• Electronic Write

3. How to Build it?

Fig1.1. LCD 16x2 display connection diagram

// Write code by Tann Thona (15/03/2017), Adviser: Chann Tola    


// include the library code:
#include <LiquidCrystal.h>

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

char Telecom[16] = {' ',' ','T','E','L','E','C','O','M',' ',' ','2','0','1','7',' '};

void setup() 
{
  // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  lcd.setCursor(4, 0);
  lcd.print("RUPP ^_^"); 
  
}// void setup 

void loop() 
{    
      lcd.setCursor(0, 1);
      for(int j=0;j<=15;j++)
      {
      lcd.print(Telecom[j]);
      }
      lcd.setCursor(0, 1);      
      delay(100);
      int swap = Telecom[15];
      for(int i=15;i>0;i--)
      {
      Telecom[i] = Telecom[i-1];
      }
      Telecom[0] = swap;
      
}      
 

4. Result

Fig1.2. Result LCD 16x2 display automatic scroll letter left to right

7 Segment 4 Digits Display

1. Objective

2. Electronic Requirement

• Arduino UNO
• USP Cable
• 7 Segment 4 digits (Cathode Type) 
• Breadboard
• Electronic Wire
• Resistor x4 (330Ohm or 220Ohm)
• Arduino pin 5 --> R1 --> 7 Segment D1
• Arduino pin 4 --> R2 --> 7 Segment D2
• Arduino pin 3 --> R3 --> 7 Segment D3
• Arduino pin 2 --> R4 --> 7 Segment D4

3. How to Build it?

Fig 1. 7 segment 4 digits display automatic count up number 0 to 9999

// Write code by Tann Thona (25/02/2017), Adviser: Chann Tola

int PIN_A = 12;
int PIN_B = 11;
int PIN_C = 10;
int PIN_D = 9;
int PIN_E = 8;
int PIN_F = 7;
int PIN_G = 6;
int DL4 = 5;
int DL3 = 4;
int DL2 = 3;
int DL1 = 2;
int i = 0;
int j = 0;
int n = 0;
int k = 0;
int h = 0;
int Arduino_Pins[7] = {PIN_A, PIN_B, PIN_C, PIN_D, PIN_E, PIN_F, PIN_G};   // an array of pin numbers to which LEDs
int Segment_Pins[10][7] = {{1,1,1,1,1,1,0}, // 0
                           {0,1,1,0,0,0,0}, // 1
                           {1,1,0,1,1,0,1}, // 2
                           {1,1,1,1,0,0,1}, // 3
                           {0,1,1,0,0,1,1}, // 4
                           {1,0,1,1,0,1,1}, // 5
                           {1,0,1,1,1,1,1}, // 6
                           {1,1,1,0,0,0,0}, // 7
                           {1,1,1,1,1,1,1}, // 8
                           {1,1,1,1,0,1,1}, // 9
                           };
int DELAY = 1;
int TIME = 0;
void digit4()
{
    digitalWrite(DL1,0);
    digitalWrite(DL2,1);
    digitalWrite(DL3,1);
    digitalWrite(DL4,1);
    for(j=0;j<7;j++)  {      
      digitalWrite(Arduino_Pins[j],Segment_Pins[i][j]);      
    }
    delay(DELAY);    
}
//=============================
void digit3()
{
    digitalWrite(DL1,1); // change 1 to 0 and 0 to 1 (for 7segment anoth type)
    digitalWrite(DL2,0);
    digitalWrite(DL3,1);
    digitalWrite(DL4,1);
    for(j=0;j<7;j++)  
    {      
      digitalWrite(Arduino_Pins[j],Segment_Pins[n][j]);      
    } // end loop j   
    delay(DELAY);
}
//==============================
void digit2()
{
    digitalWrite(DL1,1);
    digitalWrite(DL2,1);
    digitalWrite(DL3,0);
    digitalWrite(DL4,1);
        for(j=0;j<7;j++)
        {          
          digitalWrite(Arduino_Pins[j],Segment_Pins[k][j]);          
        } // end loop k
        delay(DELAY);
}
//==============================
void digit1()
{
    digitalWrite(DL1,1);
    digitalWrite(DL2,1);
    digitalWrite(DL3,1);
    digitalWrite(DL4,0);
        for(j=0;j<7;j++)
        {          
          digitalWrite(Arduino_Pins[j],Segment_Pins[h][j]);          
        } // end loop j
        delay(DELAY);
}
void setup()
{
  // put your setup code here, to run once:
  pinMode(PIN_A, OUTPUT);
  pinMode(PIN_B, OUTPUT);
  pinMode(PIN_C, OUTPUT);
  pinMode(PIN_D, OUTPUT);
  pinMode(PIN_E, OUTPUT);
  pinMode(PIN_F, OUTPUT);
  pinMode(PIN_G, OUTPUT);
  pinMode(DL1, OUTPUT);
  pinMode(DL2, OUTPUT);
  pinMode(DL3, OUTPUT);
  pinMode(DL4, OUTPUT);

}
void loop()
{
  
  for(i=0;i<10;i++) 
  {
    for(TIME=0;TIME<=250;TIME++)// Simulation (TIME=0;TIME<=250;TIME++)
    {
    digit4();   
    digit3();
    digit2();
    digit1();
    //delay(1);
    }    
    // Condition Count Up
        
            if(i==9) 
            {
              n++;
              //----------------
               if(n>9)
               {
                 k++;
                 //----------------
                  if(k>9)
                   {
                     h++;
                     //----------------
                      if(h>9)
                       {
                         h = 0;
                       } // end if(h>9)
                   } // end if(k==9)
                    //----------------
                     if(k>9)
                      {
                       k = 0;
                      }
               } // end if(n==9)
               //----------------
              if(n>9) 
              {
                n = 0;
              } // end if (n>9)
            } // end if (i==9)          
         
    } // end time
    
 } // End Void Loop
 

4. Result

Set Real Time Control Light Using 7 Segment

1. Abstract

2. Introduction

3. Objective

• Display Real Time on 7 segment
• Set Time Automatic Turn ON LED Light
• Set Time Automatic Turn OFF LED Light

4. Electronic Requirement

• Arduino Meg 2560
• RTC DS3231 Module
• 7 Segment Two Digit Cathode Type (x2)
• Button (x3)
• Resistance 330 Ohm (x6)
• LED Red(x2) Wite(x1)
• Breadboard (x1)
• USB Connected from Arduino to Computer
• Jumper Wire

5. Methodology

• Controller

Figure 1: Arduino MEGA 2560)

• RTC DS3231 Module

Figure 2: DS3231 Real-time Clock Module

• 7 Segment Cathode Two Digit

Figure 3: 7Segment Cathode Two Digit

• Button

Figure 4: Button

• LED

Figure 5: LED

5.2 Circuit Diagram

• RTC DS3231 Module

Table Connection RTC to Arduno

Figure 6: The circuit of connection from Arduino MEGA to RTC

• 7 Segment Cathode Two Digit

Table Connection 7 Segment to Arduino

Figure 7: The circuit of connection from Arduino MEGA to 7 Segment

5.3 Algorithim of Project

Figure 8: Full Diagram of Project

Flow Chart Process

5.4 Coding

//#include <SPI.h>
#include <DS3231.h> //Library for RTC module (Download from Link in article)
DS3231 rtc(SDA, SCL);
void setup()
{
Serial.begin(9600);
//SPI.begin(); /* Enable the SPI interface */
rtc.begin(); // Initialize the rtc object
rtc.setTime(13, 52, 00); // Set the time to 12:00:00 (24hr format)
rtc.setDate(13, 3, 2018); // Set the time to 12:00:00 (24hr format)
}
Void loop()
{
}

6. Result

• 7 Segment display real time clock by get time from DS3231.
• Button 2 (Middle): press a second 7 Segment will go to set time turn on LED mode. In mode set time if click less than a second on Button it will increase number on 7 Segment.
• Button 3 (Right): press a second 7 Segment will go to set time turn off LED mode. In mode set time if click less than a second on Button it will decrease number on 7 Segment.
• Button 1 (Left): press a second in set time mode it will save time value. But if we click less than a second it will change digit for edit number of time.
• LED will turn on/off when time we set the same real time.