Microcontroller › AVR › how to control room lights via pc and microcontroller › yes, you can. here i am
yes, you can. here i am pasting a ckt (edited on the link you send)….
here i had eliminated the need of diode, resistance and the NPN tansistor … instead of thatconncet a direct wire as i had did by using a green colour one… and above one a switch, instead of that use ULN 2003/ ULN 2008 IC… it a buffer IC as you cannt interface the peripherials directly to PC’s parallel port.. just for protection porpose…. and connect the diode in reverse fasion… make The ULN and prallel port ground common….don’t use the Vcc pin from prallel port.. apply VCC = relay voltage… the lengh of wire fron Parallel should not be greater then 1.4 meter… for safty keep it as 1.2m only…
let me know till where you have completed