waiiit a minute, why is a small microcontroller considered overkill but an entire PC is not? it should be the other way around!

I tried this once by using an RG bi-color LED and an old P1 machine that I got for free. I was playing around with quick BASIC and got a pseudo-PWM driver to make it light up. I have a bunch of old PC’s and using the LPT port is cheaper than buying an arduino or other things that I can’t afford (arduino is $30 or so, old PC can be free at a yard sale).

What’s a printer port? Is that some kind of new usb specification?

This is a hack?

@fartface

What if you’re 8 years old, but you still have a PC with a parallel port? And no, the answer is NOT “Don’t touch it you’ll hurt yourself.” :P

just one 1 ohm resistor. Just does not seem right for safety. I would have expected more. I agree about the price of the microcontrollers. You can pick up an old motherboard for free or peanuts. Some of the original robots were built that way. McGuyver would not have ignored the motherboard.
Good way to stay green and help save a landfill.

The current draw from this project might well exceed the capability of USB LPT adapters. Additionally, it only saves $10 over a more functional unit with SSRs or for extra credit, some transistors and a connection to the ATX/AT power supply to supply more power than you might possibly need for a small-scale LED light show.
Indeed, I’m using this method to build an 8-channel cubicle display for this Halloween.

ummm… where is the “wizards of winter” music in the backgroud?

Would it be possible to make this show HDD activity??

This was featured on instructables. I already go there, need new content that I’ve never seen…

There is actually a surprisingly decent amount of things you can still do with a lpt port. A lot of the home made CNC machines are using a LPT port for communications to the stepper controller.

Hi, I’ve been trying to map out a lighting system similar to this. I want to apply a color changing (w/intensity control)lighting arrangement for my car. I was originally thinking RGB LED’s and a standard controller, but a computer in the car seems like a better idea. Ideas?

Not a bad use of such parts.

How about making a visualizer that plays LED’s mounted in/on a case/case window, or plays light panels in/on a case/case window?

Since it is on a computer that may have network ability, put in an old wireless card, run a remote control program to access… then it’s stand alone.

Also, complaining about recycled hardware being “overkill” by comparison to a micro-controller doesn’t seem to fit with a “hacking” mentality.
//What are you doing on this site?//
This is a site about //hacking// and //reusing// “old” hardware for “new” (different) things, as well as taking new hardware and doing the same to it.

Granted this may not be earth-shattering or ground-breaking, but at the bare minimum it at least inspires ideas. Sure, we’ve been hooking different things to the parallel port for decades now and LED’s is nothing new. But the fact is that someone got a wild hair in a dark location and decided to do something with some old hardware they had laying around – and documented the process. Is it a hack? Define “hack”. To a beginner, this most certainly *is* a hack. To a seasoned -hacker- (those of us that have been doing this for decades), this should remind you of the joy you had when you were that aforementioned 8 year-old and discovered that you can hook a whole lot more to a parallel port than just a printer!

I just consider this the “easy” level stuff. Then again, an EE would consider the stuff I do to be trivial. It’s all perspective. I credit the author – let’s face it, I can’t say that I have any instructables so at least they’ve got that on me. Then there’s the time spent in programming and timing the whole thing. Again, it’s not like we just sat down and wrote something like jd edwards, but nonetheless it’s an accomplishment.

I personally would be interested in higher output. As it is it doesn’t really accomplish anything.

And why not address color mixing? Set it up with banks of RGBAW cells, so that you could point it at a white wall and tone the whole thing.

If the output can be increased (think simple transistor drivers, really up your current capability), this could rapidly become an interesting project.

And worth noting is he’s using acrylic samples he got for free, a good alternative is theatrical gel from companies like rosco or apollo, it’ll run about eight bucks for a 24″x27″ or so sheet, and can give you a much wider variety of colors (some of which are designed for mixing and use in wash instruments such as this)

How is a 70 cent micro overkill when a DSUB connector cost about twice as much.