Why Powered USB Is Going to Fail 191
An anonymous reader writes "Patrick McFarland, famous Free Software Magazine author, has written a two part article about why Powered USB is not taking off at home. (part 2 is also available) He includes a lengthy history on why USB took off in the first place, and then continues on to explain what we gain by allowing Powered USB to power all our devices."
I agree (Score:5, Interesting)
Being able to charge high draw devices through Firewire would rock. Powering my laptop from my PC would be great, especially if it will be syncing files at the same time, allowing me to leave the power brick in my laptop case and not have to get it out after getting home.
In my eagerness to get this post in first, I didn't read the article before I started typing. He says it all the same way I would. So to all of you who haven't RTFA'd, do it to find out the rest of this comment's points. Now lets see if I can still get this in first...
Re:I agree (Score:3, Interesting)
Re:I agree (Score:5, Interesting)
I'm a fan of Firewire as well, which is mainly why I wrote this article in the first place. Powered USB handles all the power issues (except for the flaws I noted in my article), and a future USB 3.0 revision will catch USB up to Firewire 800 over 9 pin cables (as opposed to the new over-CAT5 and over-Optical versions that are really for special use applications and completely outside the realm of desktop computing), so I just don't see why they don't clean up Powered USB and either integrate it into USB 3.0, or release it as a more official optional extension.
USB may have killed Firewire, but that doesn't mean USB is ready to replace it quite yet; the fact Firewire 800 was even released, and supported on non-Apple devices pretty much proves that.
USB Power Strips as notebook power supplies (Score:4, Interesting)
On USB 2.0 vs. FireWire400/800: I know that this subject as been beat to death, but anyway... Higher speed are always nice, but I am not often limited by the bus speed. What I LOVE about USB is that the specification is open. Anyone can download it. You can build your own USB gizmos in your basement; no large investment is required. There are plenty of chips that support USB available in small quantities (like 1 or 2). You can even make USB look just like a serial port, making said gizmos compatable with LABView with no driver fuss. Try that with FireWire! Now if I could make all my little lab gizmos powered off the USB bus as well, heck, I might never go home.
I know FireWire is popular for video transfer, but isn't that what DVI is for? For data transfer, you don't have to run DVI in real time, and you can run 3.9 Gbits/sec over DVI today.
Why Device Industry doesn't want Powered USB... (Score:5, Interesting)
Re:I agree (Score:4, Interesting)
One thing the author of the article missed is the original purpose of parallel and joystick ports. They were called "parallel digital input/output port" and "scientific port". The parallel port was meant for general purpose digital I/O (so you control relays or tell whether a contact is closed or not) and the scientific port could be used to connect thermocouples for example.
These were "starter" ports that made the computer useful in the lab or in the factory without purchasing additional components. Nowadays a special expansion card or external device are necessary to get back the same capability. The cheapest are around $100, but this quickly ratchets up to $1000 and more for anything capable.
One thing to keep in mind is that the original IBM PC (which was before XT and before AT) had a fairly slow processor (6 or 8 Mhz ? - can't recall) and the audio-range sampling rates of parallel port and joystick port matched them well. Nowadays we have Ghz cpus, but anything that captures faster than 100 Mhz is expensive - with Ghz cards costing more than the cost of the computer.
Re:What's the problem? (Score:2, Interesting)
This guy is proposing that ALL peripherals, big and small, should be powered by Powered USB, thus eliminating the multitude of power cords and bricks that go with all your computer peripherals.
Where do compatibility problems come into play? The Powered USB spec has three kinds of plugs, depending on the voltage supplied (5, 12 or 24).
Re:I agree (Score:3, Interesting)
It's the same 'guts' as used in those cheap aluminum USB 'laptop drive' external housings, which also get their power from the USB with no difficulty.
Re:I sincerely hope powered USB fails (Score:1, Interesting)
You know, you are a genius, yes you are!
So obvious a design fault, leading to hard to detect intermittent errors, leading to lot of technical superstition, yet none undertook the task to make it a standard requirement to ensure that all system components let the system know their power requirements and that power supply let the system know its power capacity and that system can power-down each component separately as needed... I mean, it was in depicted in Sci-Fi for decades ("power from shields to cannons" and v-v)! Besides, it is even more critical parameter then temperature (and elevated temperature is only a consequence of power expenditure) which is religiously monitored everywhere.
Wireless (Score:5, Interesting)
So? Work smarter. I have a 17" Apple MacBook Pro on my desk and it has exactly ONE cable connected to it: the MagSafe power connector.
The mouse I use (when I use one) is Bluetooth. My printer and speakers are plugged into an AirPort Express across the room. A 500GB hard drive and the big HP color laser are plugged into an Extreme in the next room, which is where the DSL line comes in and besides, it's quieter that way. Backups to the HD, while slower, are scheduled and occur in the background, so who cares how fast they happen? The network is obviously wireless, and 802.11n due to the Extreme.
I have a USB-powered Canon scanner, and I plug it in when I need to scan something (rare).
The Apple AirPort Extreme and Express are great options, and work on Macs and PCs. I think Belkin also has a wireless USB hub for PCs.
In short, if you have too many wires, then get rid of them.
It's the one-voltage spec that is stupid (Score:3, Interesting)
+12V seems like a no-brainer since the world is overrun with devices designed to operate at 12V. -12V also seems useful, especially if a circuit can use both to get a 24V rail-to-rail effect. Current PC power supplies are not designed to drive a whole lot on the -12V line, but at least the foundation is there.
The question would be what the best third choice would be. Would it cause interference issues to run, say, 90VAC at 400 Hz down the line? Devices that currently use inverters (such as scanners) would be able to drop them, while devices with high voltage demands would be able to use postage-stamp-size circuits to generate an arbitrary AC voltage. Power supplies already use intermediate stages on the way to the final +12, -12, +5, -5, +3.3 array we all know and love, maybe they can just be tapped directly at the intermediate stage.
I can understand the concerns about providing relatively high voltage AC over an easily accessible connector, but if it's properly designed it would be no more dangerous than wall outlets -- and there is generally one of those close to every stationary computer. Obviously laptops running on battery power would be ill-equipped to provide 90VAC, but mostly due to the high draw that would go along with it. When plugged in, their power bricks should be up to the task.
Whatever options are chosen, they should be be based on readily available commodity hardware. This keeps costs down, allowing the spec to attain wide acceptance. Asking current computer owners to spring $20 for a stand-alone power supply looks reasonable if it knocks $10 off the price of every device they attach to it. With just two devices -- printer and scanner for example -- they break even. If they can run other devices off it that do not use USB for data transfer (like monitors), hitting the two-device break-even point would be easily achieved. Then when they move on to the next computer, it will allow them to get rid of the extra box, but still use the peripherals they already have. Nobody would be compelled to buy the "retrofit kit" unless/until they also bought a device that requires it.
Mal-2
Double-USB connectors for 2.5" drives (Score:3, Interesting)
Re:Wireless (Score:3, Interesting)
It's marginally acceptable resolution but it's still small and low-contrast. However, I have to give on this point, because my CRT couldn't be powered off of USB anyway, since it draws up to 200W according to the UL label.
Still too small for me, and much slower.
Well, sure, if you're surfing WiFi is just fine, and 802.11n isn't too bad for now, since it is only ~70% slower than most hard drives. All assuming you don't have any problems with interference, of course. If you don't, good for you, and keep your fingers crossed.
Agreed. Three different incompatible connectors is going the wrong direction.
Why not? In the very near future a 1TB SAN need only have a single 3.5" hard drive in it, and an Epson 9600 only draws 110W so it's within the reach of powered USB. Granted, there are devices that will require auxiliary power, but they're few and far between (my big CRT is one, actually, and my big laser printer is probably another).
I used to be a huge fan of WiFi. I started using Spectrum24, before 802.11b, and moved to 802.11b back in 2000 or so, then upgraded to 802.11g as soon as it was available (before it was standardized, actually, much like 802.11n is now). After years of inadequate performance, intermittent failures due to interference and problems with device incompatibility (mostly gone now with b/g, but a big problem with n), I've decided that I prefer wired connections wherever possible. Wireless is getting faster, but by the time 802.11n with its 200Mbps has thoroughly penetrated the market, I'll be able to get 10Gbps wired Ethernet.
That said, I guess I don't actually care which wire you get rid of. If you can remove the data cable, and do it without performance, compatibility, configuration, security or reliability problems, then fine. If not, though, then it makes perfect sense to me to run power through the data cable and eliminate the extra power cable. Heck, even if you do go to wireless data transfer, give me an option to power the device through a powered USB cable, just so I don't need to muck with power strips.
Other Reasons (Score:5, Interesting)
The other advantage of USB was that the plug is simple. It's just a rectangle that goes in a rectangular hole. You can't put it in backwards. There are no screws to hold it in. It's very approachable. Unlike serial, paralell or game ports, which look like they belong in the back of the computer and not the front, USBs are safe to put on the front of just about anything. The design of the port itself invites people to use it, rather than scare them away.
These are the other reasons USB is awesome, and also yet more reasons why Powered USB will not work. Adding any sort of extra plug will just make USB scary again. The only way I see powered USB working is if you find a way to transmit that power with a connector that is identical to the existing USB port.