Hello, In the previous post, I mentioned the connections which should be made to use HD44780 16 by 2 LCD. In this project I will be exploiting some ideas from previous project to make temperature sensor and displaying the temperature on the LCD. Also, I have incorporated a light intensity measurement cum theft detect device which Displays the light intensity of surroundings on the LCD and produces a beep sound whenever someone crosses the door(i.e. light intensity is close to(or is) 0). Now, I used LM335 sensor for measuring the temperature of the surroundings by exploiting the fact that any change in temperature will change the voltage of LM335( at 0 K Voltage is 0 Volts). And for the light intensity measurement(on a scale of 0 to 10) I used a Light depending resistance(LDR), whose resistance (therefore voltage) varies as per the intensity of light falling on it. When light of high intensity is falling on LDR its resistance is less and when light of low intensity is falling on LDR its resistance is more. I have uploaded the circuit diagram and the code(I have put some extra things in the code for example: the interface would ask options from user like whether you want to display temperature or light intensity which you may want to delete so make them as comments!).
in the circuit diagram i have connected ground of arduino board to 5v. Obviously its wrong, ground of arduino should be connected to the 0Volt line(the top one).
I have made a small instructive video. Hope you enjoy it!