light meter sketch problem

hi guis ,i am new to arduino and i am trying to build a light meter (lx).I think my sketch is wrong,the lcd dont work.The serial …works fine…HELP

sketch_mar22a_LIGHTMETRtestlcd.ino (826 Bytes)

the lcd dont work

Doesn’t work in what way ?
No text on screen ?
Wrong text on screen ?
Does it work with the LCD “Hello World” example ?

Here is how you should have posted your code

//Light Intencity Measurement
//Include LCD library
#include <LiquidCrystal.h>

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

double Light (int RawADC0)
  double Vout = RawADC0 * 0.0048828125;
  //int lux=500/(10*((5-Vout)/Vout));//use this equation if the LDR is in the upper part of the divider
  int lux = (2500 / Vout - 500) / 10;
  return lux;

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

void loop()
  Serial.print("Light Intensity:");
  lcd.setCursor(0, 0);
  lcd.print("Light Intensity:");
  lcd.setCursor(0, 1);

Using code tags

No text on screen.I will learn,thanks. Lcd just have blu light and nothing else...

Has the LCD got a contrast potentiometer on the back ? Does the "Hello World" example work ?

thank you your point help me!!!!!

nektarios-25ma: thank you your point help me!!!!!

So the problem was the contrast pot ?