How would I go about adding indicator lights to some front-mounted USB ports? The case I got has a little box in the front with 2 USB ports and 2 audio jacks, USB in the middle and an audio jack on each side. I don't really want to route audio cables to the front, so I figure I would just use those holes to mount indicator lights. What pin would I wire those to, and what sort of circuit would I need? I imagine a resistor to lower voltage or some such, but I'm not really sure. Any tips?
Indicator Lights to indicate what? LED comes on when the port has something plugged in..or just on constantly?
Yeah, heh, should have made that a little clearer. I'm looking for lights to indicate when something is plugged in. Otherwise I'd just run some LEDs from a molex .
At first, I'd say put some LEDs in series with the connector, but that would not work so good, as you would loose 1.7-5 V off your USB power (depending on the LED). Series is the only way that makes sence, but the voltage loss would be unaccceptible. I'm not sure how you could do this, possibly Linear or Macroman could be of assistance...
I'm resurrecting this thread in case someone can be of anymore assistance. I really want to use this mod for an xbox mod because the controllers are just USB. So the xbox has an "extra" wire that is only used for light guns but i've already used it for a controller on/off switch. Now i guess the effect i want is the same as a normal USB indicator light. Does anyone know how it could be done? Yo-DUH_87, you said it could be done in series? how would that keep an LED from being lit all of time and not just when a device is plugged in? I don't know how much power controllers use, but it can't be too much. Much thanks to anyone who can help.
I think this should work (but then again, I still suck at these things). Use a CMOS buffer and connect it to the ground wire of the USB connector but use a large resistor. You'll need a buffer that responds to almost no current, then use the buffer to drive the LED. 1 buffer chip will probably be enough for 4 leds. This is what I mean (yeah, my art sucks big time): Code: ___ resistor __ buffer input | USB ground °-------------- USB thing -- | USB +V °--------------------------- Hm, I'm starting to believe this will work. Grr, can't find the Fairlight semiconductor page and they've got really good datasheet, Yahoo doesn't help me either . It's Fairchild, stupid me. Ok, does anyone know about a buffer chip that needs input current, not voltage, because you can't know how much voltage will be left after the usb device you plug in, but there must be current. Ok, I'm getting on to some interesting stuff . Hm, too much chips Look here (Fairchild pwns )
You can probably afford to lose around 100mV from the USB supply line, so could use a low value series resistor, then either amplify the voltage dropped across it enough to switch a transistor on, or use a comparator to detect the drop and switch the led on.
The link doesn't work. I'm not sure what this stuff is that you're talking about, but if it works i am all for it.
There should be ammeter/overcurrent protection chips between the USB 5v and the PSU, they connect to the USB controller chip through an I2C interface, try connecting a logic circuit of some kind(PIC?) to the I2C interface wires, and then have the circuit drive some LEDs. Very hard, but possible.
Actually, the controllers use quite a bit... I've modded one for a PC, and it says that it's using 400ma. I'm guessing it's so much because it's got the 2 port USB hub built into it.
maybe it does use a lot of power. I built an adapter as well, and i got a power overuse error once when i tried to use it on my keyboard hub. Either way, it seems that this will be a difficult mod to complete. Probably not worth the trouble.
couldnt u just make a small hole in the side of the usb port and put the button for a microswitch through the hole? seems a lot simpler and safer to do as the chance of frying something important isnt as high as fiddling with the already ecisting electronics
This looks OK (in simulation). I started out trying to build the first stage of a 3914, but couldn't get a single-rail version to work. R1/SW1 is the USB device. Chicken edit: a better op-amp may work on single-rail.
Wow, way to make me feel stupid. Those diagrams are a totally foreign language to me. I think you may just have to try this out on your own to see if it will work. Anyway, what about this switch thing? You mean like a common switch rigged in a position that the USB plug would push it when plugged in or something. I hope you wouldn't mean a switch that you have to push/flip manually to get it to work. That would destroy the whole point.
Have you thought about looking for the actual USB controller chip and seeing if it has a pin for activity? (Search for the chips PDF file in google)
not a normal switch. a microswitch ie a very small push switch that requires very little movement to trigger. so u make a hole in the side of the usb socket so that when the usb cable goes in it pushes the switch in and turns the light on EDIT the switched look like this from this website http://www.alca-coin.com/eng/index2.php?p=9&n1=menu
hmm.. i might be able to dremel some room inside the front panel but it would have to be perfect. About the USB controller chip, the xbox has a USB daughterboard that I would assume has all of that built in, although i haven't looked at it real closely. I don't think it would separately indicate each device being plugged in though. The daughterboard has 2 sets of plugs coming into it from the controller ports (they are paired) so i'm really not sure on that. I might have to open it up now and check.
FYI... Those switches are arcade button switches (cherry switches). You can get them in the US at Happ Controls
