hi and good day!
I am new to this world of arduino programming so please bear with me... 
i have this project called the automatic room light with visitor counter. there are some sites that offers this project base on 8051 microcontroller.
however, i want to make this project with arduino uno and i dont know how to start. can you please help me do this? i dont have any schematic either to start with but the scenario will be this:
Microcontroller is a reliable circuit that takes over the task of controlling the room lights as well as counting number of persons/ visitors in the room very accurately. When somebody enters into the room then the counter is incremented by one and the light in the room will be switched ON and when any one leaves the room then the counter is decremented by one. The light will be only switched OFF until all the persons in the room go out.
on the other site, they include the circuit for the 7 segment display. however, i dont need the dispaly in the arduino circuit. all i want is to turn on a light when visitors were in the room and turns off when no one is present in the room..
please do enlighten me.. thank you very much..
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