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Questions tagged [usb]

Universal Serial Bus; an interface standard for connecting computers and electronic devices for communication and charging.

Usage

Universal Serial Bus is a specification to establish communication between devices and a host controller (usually personal computers). Though designed for personal computers, it has become commonplace on other devices such as smartphones, PDAs and video game consoles, and is also used as a power cord for charging portable devices.

Revisions

Currently, there are three major versions of the USB specification, with USB 2.0 now being available on most devices, thus replacing USB 1. It allows a maximum theoretical bandwidth of 480 Mbit/s.

USB 3.0, a specification completed in 2008, can transmit data at up to 5 Gbit/s. USB devices are available with various connectors and cables. USB 3.0 introduces a new connector type that however remains backwards-compatible with older USB devices.

alt text
Basic trident USB Logo.

Related tags

  • lists questions about storage drives connected by USB, especially devices known otherwise as flash drive, USB stick, USB key and thumb

  • for questions specifically about the new USB 3.0 standard

  • for questions specifically about the USD 2.0 standard

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How do I place a bootable ISO on a USB drive?

What's the best way of placing a bootable ISO on a USB drive, such that the drive is bootable? ISOs such as a live Linux preview disk, Windows installation ISO, etc.
Justin White
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How do I figure out which /dev is a USB flash drive?

I want to mount a USB drive, two of them and I need two different mount points. Unfortunately, the Linux kernel underwent a name change and I can't figure out which /dev location is the right one. Is there a way to look through dmesg or /proc or…
user53981
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10 answers

Can Windows tell me what is using my USB drive?

Being the good citizen I am, I left-click on the "Safely Remove Hardware" icon in my taskbar, and select my USB drive to dismount. Then I get the message: Windows can't stop your Generic volume device because it is in use. Close any programs or…
PP.
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No USB devices available in VirtualBox

Oracle VirtualBox is unable to list/filter the USB devices attached to my system. As a result, the guest OS is not able to see any USB device either. This is my configuration: Host: VirtualBox 5.0.0 r101573 on Ubuntu 14.04, with Oracle…
mguassa
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Why do modern computer cases still have USB 2.0 ports?

I'm currently planning the setup for a new computer. As I were browsing through computer cases I realized that most modern computer cases still have a mix of USB 2.0 and 3.0 ports on the front panel. Is there a legitimate reason to still have or use…
Brettetete
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What is the power output of a USB port?

As the title says, what's the power output of a USB port? Is it a standard value, or it may change depending on manufacturer/model, and so on? If that value is not standard, how can one determine it?
Sekhemty
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Change default action on connecting a USB device

I've a device I connect to my windows computer (in this case it is an iPod but I don't believe that matters). Often when I first connect such devices a dialog will pop up giving a list of actions with a check box saying something like "do this as…
Hogan
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Should I plug my mouse into a USB 3.0 port?

I'm looking for an authoritative answer, backed by data. A friend asked me the other day whether he would benefit from plugging his mouse into a USB 3.0 port instead of an available 2.0 port. I flippantly replied that it would make no difference…
philipthegreat
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How to speed up rsync between two local disks?

I'm running rsync to sync a directory onto my external USB HDD. It's about 150 gigs of data. 50000+ files I would guess. It's running it's first sync at the moment, but its copying files at a rate of only 1-5 MB/s. That seems incredibly slow for a…
Jake Wilson
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I accidentally plugged my USB mouse into my eSata port... it works?

I'm on a Thinkpad T510 and I accidentally plugged my Razor USB mouse into the eSata port not realizing my error because it has been working fine this whole time. Does this seem a little odd?
MetaGuru
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What is the rationale behind safely removing USB media from windows PCs?

Quite often when I'm in a rush, I automatically pull out a USB pendrive or USB cable from an external hard drive from my desktop PC or laptop, without right-clicking on the safely remove icon in the system tray and unplugging via this route. So far…
Simon
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If USB is not listed in BIOS as a boot option, does that mean the machine can't boot from USB?

I just purchased an Asus Zenbook Prime UX31A-DH51 with Windows 8. I want to wipe the drive and do a clean install but USB is not listed as a boot option in the BIOS. Does this mean it is not possible? Here is a photo of my BIOS options. This is the…
Chace Fields
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What's the maximum typical speed possible with a USB2.0 drive?

I'm getting only 30MB/sec between my computer and a USB drive, despite the fact that USB 2.0 supports 480Mb/sec (or 60MB/sec) transfers. (Therefore, I'm only getting half the rated speed) Is there something present in the USB standard which should…
Billy ONeal
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Why is my USB mouse disconnecting and reconnecting randomly and often?

My mouse will reconnect/disconnect (will even hear the sounds from Windows), and the light on the bottom of the mouse will turn off/turn on as it starts working again. It really sucks to be playing a game (and happens on desktop as well) for the…
Marc
83
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5 answers

Does a USB keyboard only send signals, or does it also receive them from the computer?

The keyboard doesn't need any signal from the computer, just power, right? OR does it need to receive signals as well as send them? Edit: I didn't expect this question to generate this much interest! I asked it because I had an idle dream of…
Ne Mo
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