Chamath Vithanawasam
Published © GPL3+

Date, Time, Temperature and Humidity Display

Create an OLED screen that shows the date, time in digital and analog format, temperature and humidity.

IntermediateFull instructions provided2 hours58,851
Date, Time, Temperature and Humidity Display

Things used in this project

Hardware components

Arduino UNO
Arduino UNO
×1
DHT11 Temperature & Humidity Sensor (4 pins)
DHT11 Temperature & Humidity Sensor (4 pins)
×1
Maxim Integrated DS3231
×1
Resistor 10k ohm
Resistor 10k ohm
×1
Adafruit 128x64 OLED graphic display
×1
Breadboard (generic)
Breadboard (generic)
×1
Jumper wires (generic)
Jumper wires (generic)
×15

Story

Read more

Custom parts and enclosures

adafruit_ssd1306-master_KOASsXZpW2.zip

adafruit-gfx-library-master_2IU6g1UpF6.zip

dht_library_Xgke1ZhPls.zip

dht-sensor-library-master_Al4SeQRvaS.zip

arduinortclibrary-master_hKLoSjCilY.zip

Schematics

Breadboard diagram of the project.

Note: I could not find the proper OLED screen on Fritzing. If you need further clarification on where the pin outs from the OLED go, check the comments on the code.

Schematic of the project.

Note: I could not find the proper OLED screen on Fritzing. If you need further clarification on where the pin outs from the OLED go, check the comments on the code.

Code

Time_Temp_Humidity_Display.ino

Arduino
This is the code to compile the project. Remember to add the necessary header files, without with the project will not work.
//Greetings hackster.io users!
//Date, Time, Temperature and Humidity Display

/////////////////////////For OLED////////////////////////
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

// If using software SPI (the default case):
#define OLED_MOSI   9 //MOSI aka SDA
#define OLED_CLK   10 //CLK aka SCL
#define OLED_DC    11
#define OLED_CS    12
#define OLED_RESET 13
Adafruit_SSD1306 display(OLED_MOSI, OLED_CLK, OLED_DC, OLED_RESET, OLED_CS);

#if (SSD1306_LCDHEIGHT != 64)
#error("Height incorrect, please fix Adafruit_SSD1306.h!");
#endif
/////////////////////////////////////////////////////////////

////////////////////////////For DHT//////////////////////////
#include<dht.h>
dht DHT;
#define DHT11_PIN 3
int DHTtimer = 0;
/////////////////////////////////////////////////////////////

////////////////////////////For RTC (DS3231)//////////////////////////
//SDA to A4, SCL to A5

#define DS3231_I2C_ADDRESS 0x68
// Convert normal decimal numbers to binary coded decimal
byte decToBcd(byte val)
{
  return( (val/10*16) + (val%10) );
}
// Convert binary coded decimal to normal decimal numbers
byte bcdToDec(byte val)
{
  return( (val/16*10) + (val%16) );
}
/////////////////////////////////////////////////////////////

void setup()   
{          
  Wire.begin();      
  Serial.begin(9600);

  //set the initial time here, after setting the time, comment this section
  //DS3231 seconds, minutes, hours, day, date, month, year
  //setDS3231time(00,24,12,6,3,2,17);
  display.begin(SSD1306_SWITCHCAPVCC);
  display.clearDisplay();
}


////////////////////////////DS3231 coding//////////////////////////
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 readDS3231time(byte *second,
byte *minute,
byte *hour,
byte *dayOfWeek,
byte *dayOfMonth,
byte *month,
byte *year)
{
  Wire.beginTransmission(DS3231_I2C_ADDRESS);
  Wire.write(0); // set DS3231 register pointer to 00h
  Wire.endTransmission();
  Wire.requestFrom(DS3231_I2C_ADDRESS, 7);
  // request seven bytes of data from DS3231 starting from register 00h
  *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());
}
void displayTime()
{
  byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;
  // retrieve data from DS3231
  readDS3231time(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month,
  &year);
  // send it to the serial monitor
  Serial.print(hour, DEC);
  // convert the byte variable to a decimal number when displayed
  Serial.print(":");
  if (minute<10)
  {
    Serial.print("0");
  }
  Serial.print(minute, DEC);
  Serial.print(":");
  if (second<10)
  {
    Serial.print("0");
  }
  Serial.print(second, DEC);
  Serial.print(" ");
  Serial.print(dayOfMonth, DEC);
  Serial.print("/");
  Serial.print(month, DEC);
  Serial.print("/");
  Serial.print(year, DEC);
  Serial.print(" Day of week: ");

//////////////////////////////////////////////////////////////////

  display.setCursor(50,0);
  display.print(dayOfMonth, DEC);
  display.print(",");

  display.setCursor(91,0);
  display.print("20");
  display.print(year, DEC);
  


  if (hour<10)
  {
      display.setCursor(40,10);
      display.print("0");
      display.print(hour, DEC);
      display.print(":");
  }
    if (hour>9)
  {
      display.setCursor(40,10);
      display.print(hour, DEC);
      display.print(":");
  }
 
  if (minute<10)
  {
    display.setCursor(58,10);
    display.print("0");
    display.print(minute, DEC);
    display.print(":");
  }
  
  if (minute>9)
  {
  display.setCursor(58,10);
  display.print(minute, DEC);
  display.print(":");
  }
 
  if (second<10)
  {
    display.setCursor(75,10);
    display.print("0");
    display.print(second, DEC);
  }

  if (second>9)
  {
    display.setCursor(75,10);
    display.print(second, DEC);
  }
  
//////////////////////////////////////////////////////////////////  
//////////////////////////////FOR DAY OF WEEK/////////////////////  
  switch(dayOfWeek){
  case 1:
    Serial.println("Sunday");

    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(20,0);
    display.print("Sun");
    
    break;
  case 2:
    Serial.println("Monday");

    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(20,0);
    display.print("Mon");
    
    break;
  case 3:
    Serial.println("Tuesday");

    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(20,0);
    display.print("Tue");
    
    break;
  case 4:
    Serial.println("Wednesday");

    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(20,0);
    display.print("Wed");
    
    break;
  case 5:
    Serial.println("Thursday");

    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(20,0);
    display.print("Thur");
    
    break;
  case 6:
    Serial.println("Friday");

    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(20,0);
    display.print("Fri");
    
    break;
  case 7:
    Serial.println("Saturday");

    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(20,0);
    display.print("Sat");
    
    break;
  }


//////////////////////////////FOR MONTH/////////////////////  
   switch(month)
   {
    case 1:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Jan");
    
    break;
    
    case 2:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Feb");
    
    break;

    case 3:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Mar");
    
    break;

    case 4:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Apr");
    
    break;

    case 5:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("May");
    
    break;

    case 6:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Jun");
    
    break;

    case 7:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Jul");
    
    break;

    case 8:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Aug");
    
    break;

    case 9:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Sep");
    
    break;

    case 10:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Oct");
    
    break;

    case 11:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Nov");
    
    break;

    case 12:
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.setCursor(70,0);
    display.print("Dec");
    
    break;
   }
   
  /////////////HOUR HAND///////////////
  float x1, y1, a, b;
  const float pi = 3.14;
  a=((hour-15)*30);
  b = (a*pi)/180;
  
  x1=40+(9*cos(b));
  y1=41+(9*sin(b));

  display.drawLine(40,41, x1, y1, WHITE);

  /////////////MINUTE HAND///////////////
//  float x1, y1, a, b;
//  const float pi = 3.14;
  a=((minute-15)*6);
  b = (a*pi)/180;
  
  x1=40+(17*cos(b));
  y1=41+(17*sin(b));

  display.drawLine(40,41, x1, y1, WHITE);

  /////////////SECOND HAND///////////////
  //float x1, y1, a, b;
  a=((second-15)*6);
  b = (a*pi)/180;
  
  x1=40+(19*cos(b));
  y1=41+(19*sin(b));

  display.drawLine(40,41, x1, y1, WHITE);

   
////////////////PARTS OF THE ANALOG CLOCK THAT WILL NOT BE MOVING////////////////
display.drawCircle(40, 41, 22, WHITE);
display.drawCircle(40, 41, 1, WHITE);

display.drawLine(40, 20, 40, 25, WHITE); //12
display.drawLine(40, 63, 40, 58, WHITE); //6
display.drawLine(62, 41, 57, 41, WHITE); //3
display.drawLine(19, 41, 24, 41, WHITE); //9
display.drawLine(50, 24, 47, 28, WHITE); //1
display.drawLine(57, 31, 53, 34, WHITE); //2
display.drawLine(60, 51, 54, 48, WHITE); //4
display.drawLine(51, 58, 48, 54, WHITE); //5
display.drawLine(29, 58, 32, 54, WHITE); //7
display.drawLine(21, 51, 25, 48, WHITE); //8

display.drawLine(22, 31, 27, 33, WHITE); //10
display.drawLine(30, 23, 32, 28, WHITE); //11
  
}

void ReadTempAndHum ()
{
    int chk = DHT.read11(DHT11_PIN);

  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(70,45);
  display.print("Temp: ");
  display.print(DHT.temperature, 0);
  display.print("C");

  display.setCursor(70,56);
  display.print("Hum: ");
  display.print(DHT.humidity, 0);
  display.print("%");

Serial.print(" Humidity: " );
Serial.print(DHT.humidity, 1);
Serial.print("%");
Serial.print(" | Temperature: ");
Serial.print(DHT.temperature, 1);
Serial.println("C");
}

void loop() {

  displayTime(); // display the real-time clock data on the Serial Monitor,
 
  DHTtimer = DHTtimer + 1;

  //To ensure that the DHT is read only every 2 seconds, we make a count that goes for 2 seconds
  if (DHTtimer > 1)
  {
  display.fillRect(70, 45, 128, 64, BLACK);
  ReadTempAndHum ();
  DHTtimer = 0;
  }
  delay(1000);

  display.display();
  //The portion of the screen that shows the time and date are cleared
  display.fillRect(0, 0, 64, 64, BLACK);
  display.fillRect(0, 0, 128, 20, BLACK);
}

Credits

Chamath Vithanawasam

Chamath Vithanawasam

2 projects • 17 followers
Electronics lover

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