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USB 2 Devices Not Necessarily High-Speed
mgcsinc writes "Yahoo is running a story on how some manufacturers of "USB 2.0" devices are making hardware compatible with the USB 2.0 standard, but not necessarily its high-speed component." Sounds like the complaint raised earlier this year.
Wow. You really are as innocent as a lamb aren't you?
Look all around you. Take a very good look. Have a look at that McDonalds' "100% beef" burger that tastes like no other beef on Earth. Watch that WWE wrestling match that's about as honest as a $7 note. Watch that TV expose that shows the truth behind the "honest" business practices of Gap, Nike, etc. Read RIAA's latest claims about P2P costing its members half their sales revenues, and of a 40-speed CD burner equating to 40 actual burners. Pick up a paper and marvel at how many of your fellow citizens still think the attacks on Septemer 11th were carried out by Iraqis, or that WMDs will be found in Iraq any minute now.
The world is full of lies and deception. That isn't about to change. If you're going to stand up and complain about it, you could find a lot of better things to complain about than the possible mis-labelling (deliberate or otherwise) of a USB2 device.
I'm not trying to put you down or anything. I'm just trying to show you that this is a drop in the ocean. And complaining about drops when there are some big, kick-ass tsunamis out there is kind of ridiculous.
"Accept that some days you are the pigeon, and some days you are the statue." - David Brent, Wernham Hogg
Exactly right. About 5 weeks ago I copied a lot of files (more than 40G) from my friend's computer onto my USB 2.0 / Firewire external drive. My friend's machine did not have FW but it did have USB 2.0.
If it wasn't for the USB 2.0 connection on his machine, I might be still there at this place waiting for the files to transfer.
Other options for external USB 2.0 devices are video capture devices. You just can't fit a true DV compliant stream into 11 Mbit without lossy compression (and then it's not DV anymore.) Of course this is where firewire shines as well.
"You just can't fit a true DV compliant stream into 11 Mbit without lossy compression (and then it's not DV anymore.)"
DV is a lossy compression scheme unto itself. It starts right off at 4.1.1 and then does a block compression on top of that. Uncompressed 4.4.4 29.97fps video is like 30 megabytes or so per second.
He also wrote:
"Of course this is where firewire shines as well."
Completely agree. Firewire 1 was faster than USB 1, and now FW2 is faster than USB 2. The problem is, FW is seen as the province of Apple and Sony and the Wintel dittoheads don't want to admit that FW is better for highspeed data transfer and spend a few euros and put a superior Apple/Sony technology in their machines, Bog Ferbid. Especially as it took Apple to drag the wintel world into putting USB into Wintel computers by abandoning ADB / SVideo cable on Apple machines - the irony being that USB is an Intel technology...
Innovation in Wintel is almost impossible - they don't have the profit margins on each machine. So you pay the Apple Tax and get the latest trick kit or you pay the MS tax and run with the herd. Now, if Linux had a competent FW2 driver and a vvideo editor equal to FCP and AfterFX, I'd be all over Linux in a NY minute. But the software isn't there, so I'm sitting here on my G4 laptop editing and processing video...
RS
I pray for the day computers disappear.
Shoes for Industry. Shoes for the Dead.
USB as well as FireWire are still a single set of wires. Unless you use some sort of USB router or multiple controllers, all the devices must share a finite amount of bandwidth based on the ratio of their speeds.
For example: A device running at 2mb speed that sends 500kb in a second uses a full 1/4 of the entire USB bandwidth. This automatically chops the 12mb down to 9mb, and the 480mb down to 360mb. A 12mb device that sends 6mb cuts it in half.
By the time you have a keyboard, mouse, joystick, mp3 player, external drive, and who knows what else sharing the USB connection, you have a lot of things competing for limited bandwidth with the slower devices taking an inordinate share of the pie. This is one of the reasons I like sticking to the old PS/2 style Mouse and keyboard connectors. Keep these usually slow devices from flooding the connection. Particularily the high-res mice.
And then when you consider the 2mb/12mb/480mb numbers are the absolute maximum theoretical numbers without overhead, you realize that you get nowhere near this kind of throughput in the first place. Things can get bogged down pretty quickly.
Personally, I run two separate USB adapters. The built-in USB on the motherboard and a separate PCI USB controller. I leave all the slow things like keyboard and mouse and joysticks on one controller. I put the things that need speed like a dvd burner or mp3 player on the other one and make sure I don't use them at the same time.
Ok, fwiw, I work for a company that designs USB 2 device controllers....
The standard does allow low-,full-, and high-speed devices. Why is this a bad thing? The hardware for a high-speed (480Mbps) device is SIGNIFIGANTLY more complex than that of a full- or low-speed device. The chips are more expensive and the layout issues for making a board work with high-speed mean it's really not worth the effort for anything that doesn't really need it.
The standard is fine (in that respect, anyway...). What would be nice, however, if there was a more obvious naming scheme (if someone had asked me if a full-speed or high-speed device was faster before I made a career out of it, I probably wouldn't have known...) and if when a device got logo certified by the USB-IF they got assigned either different logo based on speed.
That said, every USB device I've used lately has said on the box which speed it was (full, high, or low)
This is false. The "bus" is made of point to point links. You connect the 1.1 mouse either to the host or a hub. If you have other devices on the bus, they are at the hub. USB 2.0 hub uses high-speed towards host also for the 1.1 devices.