Monday, 26 July 2010

LED Circuit

(Dancing Lamp # 2)

To test the program I’ve created in my previous tutorial, I use this circuit (see picture). But be careful while you connect this circuit to your parallel port. Make sure that every component is in the right place or connection, otherwise it will damage your PC !!!

I use 1 KOhm resistors. If you send an integer data = 15 to the parallel port, D0…D3 LED will be light on. And D4…D7 LED will be off.

You can arrange which LED is on or off by writing some codes in Delphi. And you can also set the delay of each step you turn on or off the LED using OnTimer event of Timer component in Delphi. I’ve created an example program for you.

Download the example program here.

Go to previous tutorial (Accessing your PC’s parallel port using Inpout32.dll in Delphi)

Go to next tutorial (The Complete Electronic Circuit)


  1. yang selau berusaha menyambung tali silaturahim mengunjungi anda.

    moga selalu sukses kawan

  2. Interesting and informative post for us and its help me to get more better idea about to design led circuit bard.

  3. Hmm.. Sounds like good. Can you please post more details about this circuit board.

    Have any of youse had any experience with any pcb assembly companies that do this?

    1. s The best and a lot of secret drop-shipping suppliers in the world which will provide your products globally available for you directly to your customers doors. Also get the best drop-shipping manufacturer on your organization.


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