How to Make a Super Simple Computer Controlled Disco Light





Introduction: How to Make a Super Simple Computer Controlled Disco Light

Hello,friends!This is my first instructable and a simple one to make.Sorry for the poor images.I don't have a good camera.This is a disco light system made of three LEDs.It is controlled by parallel port.The controller program is written in VB6.It can control the blinking speed and actually,it runs the LEDs by sending signals to parallel port output pins.

Step 1: Things You Need

For this project,you will be in need of this things:
1.Three ultrabright LEDs(Any LED should work)

2.A DB25 Connector Cable

3.Visual Basic 6 (To edit the source code)

Step 2: About the DB25 Cable

Look at the Female side of the cable(the side of the cable with holes)To make this project,you should know this pin configuration:

Step 3: Bend Your LED Pins

LEDs are polar,that means they have certain "+" and "-" electrodes.The Longer pin is "+" and the shorter is "-".Bend the pins to be fitted perfectly in the cable holes.Set the LEDs according to the diagram.After putting LEDs into the holes,this should be all you have done so far.

Step 4: Put the LED Pins Into Holes and Connect the Cable to the Port

Put the LEDs according to the diagram into correct holes.Then connect the cable to parallel port.

Step 5: Download and Start the Computer Program

Turn your PC or Laptop on.You should see the lights shining.Then download and start the Program "blinker2.exe".The lights should start blinking.You can Change their blinking rate by adjusting the slider.The source code is also included.

In order to run the program and for making any program related to parallel port interfacing,you need these files:
unzip the file.Then access the "Binaries" folder.Then from the "ocx" folder,copy the "hwinterface.ocx" to "windows\system32" folder.You should also copy the "inpout32.dll" from the "Dll" folder and paste it to "windows\system32" folder.Then run the "blinker2.exe".



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    Can I ask favor for anyone owned this project? We would like to ask permission to make project like this in visual basic. We humbly ask the codes for us to make a project which is required in our subject. You can send the codes in my email Thank you and more power.. God bless you always. :)

    my motherboard is over.foolish man

    Hey, what do I do if my computer is too new/nice? I have an old laptop running xp but it only has usb ports. How do I do this sort of stuff???

    4 replies

    there are usb to parallel port converters u can use that
    thanks for visiting and if u have any problem u can ask

    Well...usb is a bit complex one!There are many usb2parallel converter available but I heard that they are specially configured for I'm not sure...but if you study microcontroller,then you can do it with usb or usb2serial converter

    Use a FTDI chip and a bit of bit-banging in vb!!

    Hi there!
    I wish to make this project, but i cant quite figure out what pins are going in what holes? Please keep in mind im a complete novice. Maybe a clearer diagram would help?

    7 replies

    I hope this helps. Sorry the picture might look a bit strange :-) The pins (holes) which have a + plus sign next to them are where you should insert the + pins of the LEDs. The pins (holes) grouped together are ALL suitable for inserting the - pins of the LEDs.


    Ahhhhh thankyou so much! Im going to go attempt to make this project now and i will post a picture if i get it working :)

    Nice job!!!Keep it up!

    are these leds glowing with music or not?

    becoz disco light mens it should glow with music rythmn

    This is a great idea, didn't know it was possible to do something like that so cheap. For testing I connected the LEDs directly into the computer's port and ran your program, and it works great. I customized the program and I am planning to make a more advanced setup where I will connect transistors instead of LEDs, so that I can run some higher loads such as relays and finally be able to control almost anything. However there is one problem, the DB25 port is outdated and new PCs coming don't have it anymore, it's a pity I think and I would like to know if there any USB to DB25 adapters and if they would be suitable for this project. Do you have any idea?

    4 replies

    hey . . just thought u might be interested . . u can buy this 8 channel relay card which will enable you to use your printer port to control various things [{check it out =) }] working on a disco light system where i have connected 12v car neon to my psu and control them using this. . .thought u might find it interesting

    thanks.Well,USB is a complex one and you can't just program it like parallel port and yes,there are USB to Parallel port converters but I am afraid you can't use it because they are actually 36 pin connectors specially built for printers(I am not sure, if someone knows,tell me please).To use USB, you need to study microcontrollers.I am writing one.To see it,visit and don't forget to give your valuable comments.Well,if you are familier with microcontrollers,then you may know most microcontrollers come with Serial communication interface.Just buy an FT232BM chip(USB to Serial Converter) or use an USB to serial converter(Available at computer & electronics shops) and connect it to your microcontroller's USART pins(Be sure to use a level converter if using Converter) and put a program to control things.Serial port can be easily accessed by VB6

    Well, I am not familiar with microcontrollers (even though sometimes I do a bit of electronics), it would have been too good if it were this simple. If the USB to serial converter converts the USB signal to a serial signal, how come do we need a microcontroller to understand the signal, and anyway is it easy to use a microcontroller? Does it need any special hardware for programming?

    Well...serial communication means one bit at a time...while parallel communication means one or many bits at a time.To drive the LED's,you actually sent signals to three different pins.But in serial port,there is only one  pin for sending data and only one for receiving data(others are mainly status pins describing the state of transmission) and...the most vital thing...the logic level of parallel port is 5V & 0V(1 & 0) but for serial communication,the logic level is -12V & +12V(or higher) you can't just send command to your device like parallel port here.To convert this level to 5V/0V,you need a level converter which converts serial logic level to parallel logic level(Also called TTL logic),then it can be sent to microcontrollers to analyse the signal from "one wire"(this is a major fact because you can't control more than one device with this and may be not even that without microcontroller).
    Learning microcontroller is easy if you know C or Basic or assembly language.
    For programming,if you have an old PC,then don't worry.with a few simple thing,you can make your parallel/serial programmer.To know more,visit my tutorial.