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Ask Slashdot: Affordable Hardware For Remote-Booting USB Devices?
phlawed writes: USB ports are everywhere. It is very convenient for powering low-power devices, and by using a run-of-the-mill phone charger you can easily get 10+ watts or so. In other words: everyone already has the generic power supply and power cable. No issue with voltage or polarity. Perfect for the hobbyist market.
Another ubiquitous power source (in the enterprise environment) is Power over Ethernet. Active PoE splitters for 12V output are available for ~6-7 USD and up on eBay. With PoE you get networking and power over the same wires, and booting your (possibly borked) PoE device is a matter of instructing the PoE source to cycle the power on that port. (Also, USB chargers with 12V input are available for less than 1 USD on eBay. They are likely all crap, though.)
I am looking for the combination of these two concepts in a compact, affordable, quality product. I found one product offering USB power from PoE. That product appears to have left out Ethernet and has a MSRP of 30 USD. Otherwise, I find PoE wall sockets for a MSRP of USD 100 or more. It appears excessive, given the cost figures of the pieces listed above.
So, if it does not already exist... anyone feel like running with this on your favorite crowdsourcing platform? Any experienced electronics people who can do a back-of-the-envelope calculation for cost of parts and assembly?
Another ubiquitous power source (in the enterprise environment) is Power over Ethernet. Active PoE splitters for 12V output are available for ~6-7 USD and up on eBay. With PoE you get networking and power over the same wires, and booting your (possibly borked) PoE device is a matter of instructing the PoE source to cycle the power on that port. (Also, USB chargers with 12V input are available for less than 1 USD on eBay. They are likely all crap, though.)
I am looking for the combination of these two concepts in a compact, affordable, quality product. I found one product offering USB power from PoE. That product appears to have left out Ethernet and has a MSRP of 30 USD. Otherwise, I find PoE wall sockets for a MSRP of USD 100 or more. It appears excessive, given the cost figures of the pieces listed above.
So, if it does not already exist... anyone feel like running with this on your favorite crowdsourcing platform? Any experienced electronics people who can do a back-of-the-envelope calculation for cost of parts and assembly?
The summary suggests that POE is a "ubiquitous power source", but the suggests that we have to go to the bay of thieves to take a chance on getting one. Which is it?
I'm an American. I love this country and the freedoms that we used to have.
You are trying to generalize your question too much. Just say what you want to do.
It seems like you just need to combine your POE adapter with a USB "lipo" adapter.
The latter are meant to attach to a lipo battery (7.4V - 22.2V) and provide 5V for USB charging.
(Of course, you can use any DC power source as input, not just lipo batteries.)
You can search Ebay for "usb lipo mobile charger" to find them, starting at $5 for basic ones.
If you use the cheapest-possible PoE injector/splitters, which are just over a dollar, they give you a barrel jack out the side. Then you just plug your cables in. So all you need is a way to get that barrel jack out to your 5V power supply, and an appropriately high-voltage wall wart to feed it power over the PoE wires. You're overcomplicating this problem. Do not use 12V, though, if you can avoid it. Use something higher, like 17V. 17VDC wall warts and bricks are readily available, and virtually all of the cheap 5V supplies that are even vaguely wide input will run on 8-18V or so. You'll have to do the math. Actual by-the-specs PoE runs 24V so that there will be something useful at the other end. Looks like if you really scrap the bottom of the barrel you can get 5V@2A for $1 (2-24V input) but I'd go ahead and spend as much as $3 or $4 and get something which claims to do 5A if I wanted 2A. I use a lot of these cheapass eBay power supplies and whatnot and they are cheap enough to just overspecify them grossly, unless space is a serious consideration. Then you might start looking at what chips they are using and reading datasheets.
You're looking at $10 all in between a wall wart, two injector/splitters, a barrel connector, and a 2-24V to USB connector boost/buck converter. If you're really crafty, you might get that into the splitter.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
You mean something like this? http://www.vidabox.com/kiosks/...
What dafuq are you actauloly looking for. You spent so much time describing supposedly unwanted stuff, that I can;t figure out what you want.
It sounds like you want a PoE device that provides USB power, but you're a cheap bastard and $30 is too high for you. So...
$19 http://www.ebay.com/itm/iDocx-iPower-POE-to-USB-Converter-/181992770079?hash=item2a5f9d4a1f:g:eioAAOSwqrtWmVbu
$21 http://amzn.to/1nIeoNw
... using LM2596HV on a pre-assembled board. Works just fine with real (48V) PoE.
Search at Aliexpress et al.
The http://www.z-wave.com/ protocol might work. There are a lot of remote hardware/switch options out there. You could wire in a zwave switch to your power supply. Then set the bios to autoboot on power.
There is or can be built a machine that can simulate any physical object. -Church-Turing principle
$79 for a PoE converter? Are you kidding? Even teh OP said that he found one for $30.
Here is a USB power that extracts form PoE and has ethernet pass-through. This one is marketed towards powering a Raspberry Pi via PoE but there are lots of similar and similarly cheap options that can charge your iPad, if you have a PoE source, for way less than $79 or even the OP's $30.
USB chargers with 12V input are available for less than 1 USD on eBay. They are likely all crap, though.
No, they are not all crap. A switching regulator from 12V down to 5V is a much simpler thing than a 90V-240V to 5V power supply, so it should not be surprising that you can get the low voltage parts very cheaply. If you pay more than 1USD, then someone else pockets the difference and you get the exact same hardware.
Battery.
Whats wrong with a rasberry pi for $35? Swap the powersource for a USB charger.
The computer named Chip is even smaller.
Slap some duct tape on it and you are good to go if it a hobby or get a really cheap plastic box if its for the enterprise.
But what are you going to use it for?
Doing low power computing? Use a laptop. the computer you are reading Slashdot is powerful enough.
Why would an enterprise want a usb/poe powered computer? You can just buy a phone really cheap and use the wifi and the included charger.
What is the purpose of the computer?
Not the cheap as cheap can be use the spare wires in 10/100 but the 1000bt ones like a TL-POE10R. 12/9/5v handles 10w 15 bucks. Getting a 2.1mm barrel jack to usb is easy enough.
No sir I dont like it.
you've mentioned PoE, USB and 12V power sources. what you failed to mention is what the hell you actually want. do you want PoE to 12V? do you want PoE to USB? do you want an SBC powered by PoE that boots off a USB stick? what the hell do you want?
Anons need not reply. Questions end with a question mark.
How about just using a simple 5V power regulator? Ground on 0v on both cables vin on 12v from poe and vout on 5v usb. Just add a dissipador if you guna use it on high load. https://www.sparkfun.com/produ...
Are you kidding? A device standard that supplies 5V but needs VERY precise 3.6V on its data lines? A device standard where the protocol is VERY picky with its timing and pretty much requires you to either use silicon that can talk USB out of the box (which then requires a bunch of very funky additional bits and pieces and you may hope that it's not only available as BGA, you may dream about getting a DIL chip) or requires you to write very well timed assembler code and STILL would require its own chip if you dare to clock it at less than 20MHz... provided USB 1.1 is enough for your needs. You want more? You better have a way to pump 50+MHz out of that chip.
USB may be much. It's very user friendly and "plug and play" and whatnot, but one thing it ain't: A hobbyist's wet dream.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
With your ability to communicate so clearly,
you should become a political speech writer.
REALLY
What the fuck are you asking????
POE is massively less common than 12V and you can build a 12V wifi controlled switch for less than $5.00 Anything commercial will be a very very niche device and will cost a lot.
What is more common, 120-240V AC. That is the absolute most common power on this planet. and Ethernet controlled AC switches are plentiful and easy to get.
Stop being a cheap bastard and buy one. $79.00 on amazon.
http://www.amazon.com/gp/produ...
If that is too expensive, then build one from a MSP8266 or get a better job.
Do not look at laser with remaining good eye.
How the hell did this story get posted? I'm not even sure what this guy wants, what he's trying to do etc? I talks about powering devices yet the headline is about remote booting devices? Huh?
What the hell is this crap?
How the hell did this rambling incoherent question get posted to the FRONT PAGE of Slashdot?
http://www.amazon.com/WT-AF-5v...
Did not take much google fu to find this sucker. 5v output from POE and passthrough to boot.
SD
âoeWho knew something as harmless as willful ignorance could end up having real consequences?â
Cheap, reliable, fast. Pick two.
This Kickstarter project: https://www.kickstarter.com/pr..., which has just announce that it's shipping (with the usual delays hopefully over), seems like it's already solved the major issues, and just needs a hardware refactoring to produce the USB connection you're looking for.
I'd recommend getting in-touch with the creators and see if they'd be interested in developing this. This is their second Kickstarter project (at least), so they've already learned a lot, so could be positioned well to run with it.
Give a hand, not a hand-out.
Just decouple the onboard shard-frame from a USB-bearing-spindle and then re-couple it to the lookup table with a multivariate demodulator powered from the blinker fluid reserve tank next to the Turbo Encabulator girdle spring. But don't use the ones made of Amulite, use the old-style ones with the tremi pipe.
Just cruising through this digital world at 33 1/3 rpm...
Ubiquiti mPower 8-Port Power Strip Ethernet WiFi. Turn on or off any device from anywhere in the world. $98 for 8 devices = $12.25 per device.
http://www.ebay.com/itm/121863...
Let's make like a bird... and get the flock outta here.
I have wanted an easily power-controllable port to hook up USB lights to. There are several good ones, as well as cheap ones; I have mostly GoalZero. Right now, I use an Insteon switching module with an Apple USB power supply driving the lights. Goofy solution, and $50 if you have an extra power supply laying around.
What I wish I had was a power outlet with built-in zigbee controlled USB charging ports.
Try making your own PoE Splitter. 1. Send pins 4,5,7 and 8 to a PoE USB Splitter of your choice for USB power and then send pins 1, 2, 3 & 6 for 100BASE-TX Ethernet. 2. PXE Boot will still work. 3. USB power can be cycled in software. You'll need: 1x RJ45 Cat5 Network Lan Cable Crimpers 1x RJ45 Female Connector 2x RJ45 Male Connectors 5 or 6 feet of CAT5 or 6 LAN cable or as little as 12" for smaller splitters.
Dangle an LM7805 linear regulator off the PoE. Done.
How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
This should be easy. Controller could be Raspberry Pi, Arduino with HC-05, ESP wifi etc. Say $5.
12V, 10A relay is $0.50
buck converter, step down, 3A is $0.70.
Then you need a power supply. Modern PC power supplies are able to deliver all as 12V (PoE standard). The buck converter will accept 5.7V -> 20V or so. So voltage drop on line no issue. Or get a 12V, 6A PSU for $10.
10 pairs of JST connectors $2.49
So if you want 4 ports, the cost would be $5 + $2 + $2.8 + $10 + $2.49 + little time = $23 - with the PSU being most important, and being 72W it is scalable. If average device is consuming 1A, it is 5W, and it will handle 14 ports. Get a smaller PSU and stay under $20.
The issues is keeping the power inject/extraction Cat 5E. But if you want to to DIY cables, you could just cut the connector, put a new connector on, and solder an injection connector on, say JST-style on for power.
It's time for Ubiquiti to cut the shit and dump its proprietary and craptacular "passive PoE".
Ubiquiti presently has four separate(15VDC, 24VDC, 48VDC and 50VDC) and completely incompatible "passive PoE" power supplies just itching to smoke your equipment and it's ludicrous. I understand that they have a lot of deployed equipment and that they are, to some extent maintaining compatibility, but it's past time to rip the scab off and switch everything to standards based 802.3at.
While it was perhaps acceptable early on when everything they produced was 24VDC "passive PoE", their entire system is now absurd and becomes even more so with every release of a new "passive PoE" scheme from them!
Take a look at this one;
http://lavalink.com/products/samsung-galaxy-tab-usb-adapters-hubs-poe-hubs-2/poe-usb-lan-power-hub-2-2/
Ethernet passthrough, active POE and output of a 5v DC for USB devices.
And as I recall when I spoke to them, they're a reasonable price, of less than 100$ cad, or were before the dollar crashed.
Anything for less than ~35$ is probably sub par quality, or doesn't have the voltage stabilization or POE that will stand up for long term use.