Light Meter Programming

/*
  LiquidCrystal Library - Hello World
 
 Demonstrates the use a 16x2 LCD display.  The LiquidCrystal
 library works with all LCD displays that are compatible with the
 Hitachi HD44780 driver. There are many of them out there, and you
 can usually tell them by the 16-pin interface.
 
 This sketch prints "Hello World!" to the LCD
 and shows the time.
 
  The circuit:
 * LCD RS pin to digital pin 12
 * LCD Enable pin to digital pin 11
 * LCD D4 pin to digital pin 5
 * LCD D5 pin to digital pin 4
 * LCD D6 pin to digital pin 3
 * LCD D7 pin to digital pin 2
 * LCD R/W pin to ground
 * 10K resistor:
 * ends to +5V and ground
 * wiper to LCD VO pin (pin 3)
 
 Library originally added 18 Apr 2008
 by David A. Mellis
 library modified 5 Jul 2009
 by Limor Fried (http://www.ladyada.net)
 example added 9 Jul 2009
 by Tom Igoe
 modified 22 Nov 2010
 by Tom Igoe
 
 This example code is in the public domain.

 http://www.arduino.cc/en/Tutorial/LiquidCrystal
 */

// 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);

void setup() {
  // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.print("hello, world!");
}

void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):
  lcd.setCursor(0, 1);
  // print the number of seconds since reset:
  lcd.print(millis()/1000);
}

// 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);
int val = 0;
void setup()
{
 // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);

}

void loop()
{
val = analogRead(0)/4.011764;
if (val > 252)
 {
  selectLineOne();
  delay(50);
  lcd.print("It is very dark ");
  selectLineTwo();
  delay(50);
  lcd.print("in this room.");
  delay(100);
 }
if (val > 246 && val < 252)
 {
   selectLineOne();
   delay(50);
  lcd.print("It is pretty   ");
  selectLineTwo();
  delay(50);
  lcd.print("dark here.	 ");
  delay(100);
 }
if (val > 235 && val < 246)
 {
   selectLineOne();
   delay(50);
 lcd.print("It is pretty     ");
  selectLineTwo();
  delay(50);
  lcd.print("bright here.	");
  delay(100);
 }
if (val < 235)
{
  selectLineOne();
   delay(50);
  lcd.print("It is bright	  ");
  selectLineTwo();
  delay(50);
 lcd.print("in this room.	");
  delay(100);
}
}

void selectLineOne(){  //puts the cursor at line 0 char 0.
   lcd.print(0xFE, BYTE);   //command flag
   lcd.print(128, BYTE);    //position
}
void selectLineTwo(){  //puts the cursor at line 0 char 0.
   lcd.print(0xFE, BYTE);   //command flag
   lcd.print(192, BYTE);    //position
}
void clearLCD(){
   lcd.print(0xFE, BYTE);   //command flag
  lcd.print(0x01, BYTE);   //clear command.
}
void backlightOn(){  //turns on the backlight
    lcd.print(0x7C, BYTE);   //command flag for backlight stuff
    lcd.print(157, BYTE);    //light level.
}
void backlightOff(){  //turns off the backlight
    lcd.print(0x7C, BYTE);   //command flag for backlight stuff
    lcd.print(128, BYTE);     //light level for off.
}
void serCommand(){   //a general function to call the command flag for issuing all other commands
  lcd.print(0xFE, BYTE);
}

// 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);
int val = 0;
void setup()
{
 // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);

}

void loop()
{
val = analogRead(0)/4.011764;
if (val > 252)
 {
  selectLineOne();
  delay(50);
  lcd.print("It is very dark ");
  selectLineTwo();
  delay(50);
  lcd.print("in this room.");
  delay(100);
 }
if (val > 246 && val < 252)
 {
   selectLineOne();
   delay(50);
  lcd.print("It is pretty   ");
  selectLineTwo();
  delay(50);
  lcd.print("dark here.	 ");
  delay(100);
 }
if (val > 235 && val < 246)
 {
   selectLineOne();
   delay(50);
 lcd.print("It is pretty     ");
  selectLineTwo();
  delay(50);
  lcd.print("bright here.	");
  delay(100);
 }
if (val < 235)
{
  selectLineOne();
   delay(50);
  lcd.print("It is bright	  ");
  selectLineTwo();
  delay(50);
 lcd.print("in this room.	");
  delay(100);
}
}

void selectLineOne(){  //puts the cursor at line 0 char 0.
   lcd.print(0xFE, BYTE);   //command flag
   lcd.print(128, BYTE);    //position
}
void selectLineTwo(){  //puts the cursor at line 0 char 0.
   lcd.print(0xFE, BYTE);   //command flag
   lcd.print(192, BYTE);    //position
}
void clearLCD(){
   lcd.print(0xFE, BYTE);   //command flag
  lcd.print(0x01, BYTE);   //clear command.
}
void backlightOn(){  //turns on the backlight
    lcd.print(0x7C, BYTE);   //command flag for backlight stuff
    lcd.print(157, BYTE);    //light level.
}
void backlightOff(){  //turns off the backlight
    lcd.print(0x7C, BYTE);   //command flag for backlight stuff
    lcd.print(128, BYTE);     //light level for off.
}
void serCommand(){   //a general function to call the command flag for issuing all other commands
  lcd.print(0xFE, BYTE);
}

int photocellPin0 = 0; // the cell and 10K pulldown are connected to a0
int photocellReading0; // the analog reading from the analog resistor divider
float Res0=10.0; // Resistance in the circuit of sensor 0 (KOhms)
// depending of the Resistance used, you could measure better at dark or at bright conditions.
// you could use a double circuit (using other LDR connected to analog pin 1) to have fun testing the sensors.
// Change the value of Res0 depending of what you use in the circuit
// 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);
int val = 0;
void setup()
{
// set up the LCD's number of columns and rows:
lcd.begin(16,1);
}
void loop(void) {
photocellReading0 = analogRead(photocellPin0); // Read the analogue pin
float Vout0=photocellReading0*0.0048828125; // calculate the voltage
int lux0=104.1*Vout0; // calculate the Lux
// Print the measurement (in Lux units) in the screen
lcd.print(" Lux\t");
lcd.print(lux0); // Print the measured level at pin 0
delay(100);
// turn off automatic scrolling
lcd.noAutoscroll();
}