The Simple Clock just got an upgrade!

Having a digital clock that is active the whole day does not only consumes a lot of electricity but might damage the lcd in the short term so I thought I should add another feature to automatically turn off the lcd. This clock is meant to sit on a desktop so I will be too lazy to push  a button just to check the time. A perfect solution to this is to add an Ultrasonic sensor module. With this device connected to an Arduino, all I have to do is to place my hand at least 40cms away from it and it turns on the lcd automatically.

Here is how I connected the ultrasonic sensor to the Aceduino:

There are quite a few sample sketches on the web how to make the ultrasonic sensor work and based on my experience, I was able to make it work in just a about 5 mins because all I have to do is cut and paste the code and added an indicator at the buttom of the lcd to show the current measurement being made by the sensor.

To turn on-off the lcd via code is very simple, it is just an if-then-else statement and setting all digital pins used by the lcd to input to turn it off and output to turn it on.

Here is the sample video of the working digital clock:



And finally here is the sketch I used:

#include <Adafruit_GFX.h>
#include <Adafruit_PCD8544.h>
#include "Wire.h"

#define DS1307_ADDRESS 0x68
byte zero = 0x00; //workaround for issue #527
// pin 7 - Serial clock out (SCLK)3
// pin 6 - Serial data out (DIN)4
// pin 5 - Data/Command select (D/C)5
// pin 4 - LCD chip select (CS)7
// pin 3 - LCD reset (RST)6
Adafruit_PCD8544 display = Adafruit_PCD8544(3, 4, 5, 7, 6);
#define echoPin 8 // Echo Pin
#define trigPin 9 // Trigger Pin
#define NUMFLAKES 10
#define XPOS 0
#define YPOS 1
#define DELTAY 2
float i;
float ii;
float yy;
int xk;
int xl;
  int second1;
  int minute1;
  int hour1; //24 hour time
  int weekDay1; //0-6 -> sunday - Saturday
  int monthDay1;
  int month1;
  int year1;
#define LOGO16_GLCD_HEIGHT 16
#define LOGO16_GLCD_WIDTH  16

long duration, distance; // Duration used to calculate distance
long distance1;
void setup()   {
    Wire.begin();
  Serial.begin(9600);
  pinMode(10, OUTPUT);
  analogWrite(10, 950);
  display.begin();
  display.clearDisplay();
  display.setContrast(45);
//Ultrasonic sensor settings
   pinMode(trigPin, OUTPUT);
   pinMode(echoPin, INPUT);

//setDateTime();
}

void loop() {
//  analogWrite(10, ii);

 digitalWrite(trigPin, LOW);
// delayMicroseconds(1);

 digitalWrite(trigPin, HIGH);
// delayMicroseconds(5);

 digitalWrite(trigPin, LOW);
 duration = pulseIn(echoPin, HIGH);

 //Calculate the distance (in cm) based on the speed of sound.
 distance = duration/58.2;

  printDate();
i = i + 0.05;
if(xk==1)
{
yy = (sin(i) * 4) + 34;
    display.drawPixel(i*2.95, yy, WHITE);
yy = (sin(i*-1) * 4) + 34;
    display.drawPixel(i*2.95, yy, WHITE);
}
else
{
yy = (sin(i) * 4) + 34;
    display.drawPixel(i*2.95, yy, BLACK);
yy = (sin(i*-1) * 4) + 34;
    display.drawPixel(i*2.95, yy, BLACK); 
}
  display.display();
  delay(50);
 
 if(i>33){
  ii++ ; 
  i=0;
  //display.clearDisplay();
   second1=0;
   minute1=0;
   hour1=0;
   weekDay1=0;
   monthDay1=0;
   month1=0;
   year1=0;
   if(xk==1)
   {
     xk = 0;
   }
   else
   {
    xk=1;
   } 
 }

 if(ii>1){
 xl = 1;
 pinMode(10, INPUT); //turns off the backlight

// turns off the lcd
 display.setContrast(0);
    pinMode(3, INPUT);
    pinMode(4, INPUT);
    pinMode(5, INPUT);
    pinMode(5, INPUT);
    pinMode(7, INPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  ii=0;
 }

  if((distance<40) and (xl==1)){//turns on the lcd
xl = 0;
ii=0;
 pinMode(10, OUTPUT);//turns on the back light

// power_twi_enable();
    pinMode(3, OUTPUT);
    pinMode(4, OUTPUT);
    pinMode(5, OUTPUT);
    pinMode(5, OUTPUT);
    pinMode(7, OUTPUT);
display.setContrast(45);
 }
}
void setDateTime(){

  byte second =      15; //0-59
  byte minute =      00; //0-59
  byte hour =        16; //0-23
  byte weekDay =     2; //1-7
  byte monthDay =    26; //1-31
  byte month =       11; //1-12
  byte year  =       13; //0-99

  Wire.beginTransmission(DS1307_ADDRESS);
  Wire.write(zero); //stop Oscillator

  Wire.write(decToBcd(second));
  Wire.write(decToBcd(minute));
  Wire.write(decToBcd(hour));
  Wire.write(decToBcd(weekDay));
  Wire.write(decToBcd(monthDay));
  Wire.write(decToBcd(month));
  Wire.write(decToBcd(year));

  Wire.write(zero); //start

  Wire.endTransmission();

}

byte decToBcd(byte val){
// Convert normal decimal numbers to binary coded decimal
  return ( (val/10*16) + (val%10) );
}

byte bcdToDec(byte val)  {
// Convert binary coded decimal to normal decimal numbers
  return ( (val/16*10) + (val%16) );
}

void printDate(){

  // Reset the register pointer
  Wire.beginTransmission(DS1307_ADDRESS);
  Wire.write(zero);
  Wire.endTransmission();

  Wire.requestFrom(DS1307_ADDRESS, 7);

  int second = bcdToDec(Wire.read());
  int minute = bcdToDec(Wire.read());
  int hour = bcdToDec(Wire.read() & 0b111111); //24 hour time
  int weekDay = bcdToDec(Wire.read()); //0-6 -> sunday - Saturday
  int monthDay = bcdToDec(Wire.read());
  int month = bcdToDec(Wire.read());
  int year = bcdToDec(Wire.read());
 
  display.setTextSize(1);


     if(month!=month1)
  {
  display.setCursor(10,0); 
  display.setTextColor(WHITE);
   display.print(month1);
  display.setCursor(10,0); 
    if((month<=10) and (month>0))
  {
    display.print("0");
  }    
  display.print(month1);
    display.setCursor(10,0);
  display.setTextColor(BLACK);
    if(month<10)
  {
    display.print("0");
  }
  display.print(month);
 
  month1 = month;
   }       

 
 

   display.setCursor(26,0);
  display.print("/");
 

     if(monthDay!=monthDay1)
  {
  display.setCursor(34,0); 
  display.setTextColor(WHITE);
   display.print(monthDay1);
  display.setCursor(34,0); 
    if((monthDay<=10) and (monthDay>0))
  {
    display.print("0");
  }    
  display.print(monthDay1);
    display.setCursor(34,0);
  display.setTextColor(BLACK);
    if(monthDay<10)
  {
    display.print("0");
  }      
  display.print(monthDay);
  monthDay1 = monthDay;
   }       

   display.setCursor(50,0);
  display.print("/");
 

    if(year!=year1)
  {
  display.setCursor(58,0); 
  display.setTextColor(WHITE);
   display.print(year1);
  display.setCursor(58,0); 
    if((year<=10) and (year>0))
  {
    display.print("0");
  }  
  display.print(year1);
    display.setCursor(58,0);
  display.setTextColor(BLACK);
     if(year<10)
  {
    display.print("0");
  }    
  display.print(year);
  year1 = year;
   }      

display.setTextSize(2);
    if(hour!=hour1)
  {
  display.setCursor(0,12); 
  display.setTextColor(WHITE);
    display.print(hour1);
  display.setCursor(0,12); 
    if((hour<=10) and (hour>0))
  {
    display.print("0");
  }  
  display.print(hour1);
    display.setCursor(0,12);
  display.setTextColor(BLACK);
     if(hour<10)
  {
    display.print("0");
  }  
  display.print(hour);
  hour1 = hour;
   }    

   display.setCursor(21,12);
  display.print(":");
 

    if(minute!=minute1)
  {
  display.setCursor(31,12); 
  display.setTextColor(WHITE);
    display.print(minute1);
  display.setCursor(31,12); 
    if((minute<=10) and (minute>0))
  {
    display.print("0");
  }
  display.print(minute1);
    display.setCursor(31,12);
  display.setTextColor(BLACK);
      if(minute<10)
  {
    display.print("0");
  }
  display.print(minute);
  minute1 = minute;
   }  

   display.setCursor(52,12);
  display.print(":");

  
  if(second!=second1)
  {
  display.setCursor(60,12); 
  display.setTextColor(WHITE);
  display.print(second1);
  display.setCursor(60,12); 
    if((second<=10) and (second>0))
  {
    display.print("0");
  }
  display.print(second1);
    display.setCursor(60,12);
  display.setTextColor(BLACK);
    if(second<10)
  {
    display.print("0");
  }
  display.print(second);
  second1 = second;
   }  
   display.setTextSize(1);
    if(distance!=distance1)
  {
  display.setCursor(34,40); 
  display.setTextColor(WHITE);
   display.print(distance1);
  display.setCursor(34,40); 
    if((distance<=10) and (distance>0))
  {
    display.print("0");
  }    
  display.print(distance1);
    display.setCursor(34,40);
  display.setTextColor(BLACK);
    if(distance<10)
  {
    display.print("0");
  }
  display.print(distance);
 
  distance1 = distance;
   }     

}