View Full Version : Controlling LEDs using Parallel Port

05-22-2005, 09:41 PM
I am a newbie to Electronics, and have 0 practical knowledge in making circuits. I was planning to interface the Parallel port to light up some LEDs. My MB costs ~Rs. 8000 and i dont want to fry it... So I would appretiate any precautions before I go ahead with this.

From what I read, an LED in series with a 1 K Resistor between the data port and the GND will do the trick. Please tell me if there is any chance of mess-ups....

Thanks in advance....

05-22-2005, 11:20 PM
there are many articles on the site dealing with this ( follow them properly and u wont screw up ) ..

05-23-2005, 02:19 AM
u haven't told abt which programming language u r using

There are a no.of tutorials in this site

If you are interfacing in C

just joing yahoo group-parallelport

and download the following files
parallel port for u book
parallel port for u(updated)

Then first install userport then start programming in C,then u just connect
LED to the data port (any pins D0-D7), there won't be any need for LED"S mostly bcz the parallel port voltage is <4.5 or u put 150ohm series with LED

Then do Bios settings and install userport

then execute the following program

void main()

This pgm will glow LED's connected to D0,D1,D2,D3

Bibin John

05-23-2005, 01:25 PM
u haven't told abt which programming language u r using

There are a no.of tutorials in this site

I am planning to use C, but on linux platform. I am planning to write a character device driver (to be loaded as a module) which will interface with the parallel port. Then I can use ordinary C programs/shell scripts to interface the parallel port using the character device.

I went through the tutorials and they are really great. they are exactly what an electronics dummy like me would need for starting. I am yet to buy the stuff.... so i will be starting in about a week or so.