USB toy with software dimmer??

I'm looking or ANY usb device that has a capability for basic voltage control with software. Examples are to dim or bright an LED, control something with steps in between on/off, etc.

Doesn't matter what it is AT ALL other than availability, reasonable size and price.
Also it doesn't have to control its own voltage.

Any ideas?

PS you could ask what its for but you could also guess

 

Seriously? No one on these forums has ever used a USB device with software do a basic hardware function?

 

You're probably gonna wanna look at something like this: Arduino - HomePage You might have to look into other microcontrollers, too.

 

LEDs cannot really be 'dimmed' due to the way the LED works. LEDs are generally dimmed using pulse-width modulation that simulates a strobe effect our eye cannot detect.

There are LEDs that dim on the back of Razer mice, but they are not software controlled.

I believe internal lighting on Alienware (AlienFX) systems uses PWM to dim. The speed can be software controlled. It is connected via an internal USB hub on the motherboard. I have seen them pop up on Ebay from time and time again. I believe it was called the AlienFX Rev5 Controller Card. Generally your best bet would be to buy an entire P2 chassis with the lighting included.

I have not, however, found a product with an actual LED that can have it's brightness controlled via software.

Regardless, start googling PVM controller or PWM USB interface until you find something that will suit the needs of your project.

 

Seen that. Going for something cheaper and easier.

Thats all very interesting to me (sorry for truncating) shows how much I know about LEDs. Its good to know but for another project...
You see, I was only using LEDs as an example. Had I known that they needed PWM for dimming I wouldn't have mentioned them. I basically just need a software potentiometer/trimmer.

I just had an idea.
With a USB sound card, you could control everything with volume control and generate PWM with synth software.
Of course the watts and voltage are not very much but still... I'd bet this idea could save a lot of people a lot of time.

I was going to say too bad I don't have one to experiment with but of course my built in audio will work just a well SO... I'll be reporting back in a little while with my findings, see if I can do what I had in mind

 

Kind of reminds me of that parody video where they turned an iPod into a taser by splitting the headphone cable and playing an audio clip.

>_>

 

And there is also current limiting.


A quick google gives Delcom Products - USB Visual Signal Indicator Lights

Sample software.

 

I may have misspoken. You can dim an LED both ways, it's just PWM method is far better. Dimming LEDs by varying the current is nonlinear and produces strange effects at lower levels of current. The light drop off is extremely fast. When stacking LEDs this becomes even more of a problem.

That is why PWM is used, since it runs the LED at 100% brightness - but only for a short pulse. Then it is switched off. Repeating this extremely quickly like a strobe light makes it seem like the LED is at full power.

@OP, any details on what your actual project is? It seems mysterious.

 

That looks fun I wish that sort of thing was available when I was building robotic stuff...

You can use a serial port, convert from digital to analogue (DAC), then use a power amplifier to boost the amp. I don't know if there are ICs that take in USB signals and convert to analogue, I won't be surprised if there are. It's probably simple to build by oneself, though the actual application matters too, and it depends on how skilled you are.

 

arduino is definitly the cheapest/eseaiest way to go around at 20$ the board and 2$ for 50 led

as for software if all you wishes is not to have to mess around then i can provide you my software wich just does that control PWM on all port

 

If you don't mind putting some hardware and software together then the Arduino suggestion would definitely be the way to go, you could do everything you wish to do with such a setup.

I also make an open source Arduino based LED lighting controller with a USB port and 2 independent RGB LED outputs as well software to set the output colors/modes/etc and there even is a virtual serial port interface provided over the USB connection so you could write scripts such as to blink an output when you get an email or something. So if you are more interested in something ready made, which you seemed to prefer in your original post, then google "Computer Color Cannon led light" to find more information or just ask me. You can also see a video of the controller in action here:

YouTube - Computer Color Cannon open source RGB LED controller software demonstration

Good luck.