rajpurkar/squad huggingface dataset:
Title: USB

As with previous USB versions, USB 3.0 ports come in low-power and high-power variants, providing 150 mA and 900 mA respectively, while simultaneously transmitting data at SuperSpeed rates. Additionally, there is a Battery Charging Specification (Version 1.2 – December 2010), which increases the power handling capability to 1.5 A but does not allow concurrent data transmission. The Battery Charging Specification requires that the physical ports themselves be capable of handling 5 A of current[citation needed] but limits the maximum current drawn to 1.5 A.

Question: What are the power variants in USB 3.0 ports?
Answer: low-power and high-power

Question: What do the power variants provide?
Answer: 150 mA and 900 mA respectively

Question: What does the Battery Charging Specification do?
Answer: increases the power handling capability to 1.5 A

Question: What is a downfall of the Battery Charging Specification?
Answer: does not allow concurrent data transmission
Title: USB

A January 2013 press release from the USB group revealed plans to update USB 3.0 to 10 Gbit/s. The group ended up creating a new USB version, USB 3.1, which was released on 31 July 2013, introducing a faster transfer mode called SuperSpeed USB 10 Gbit/s, putting it on par with a single first-generation Thunderbolt channel. The new mode's logo features a "Superspeed+" caption (stylized as SUPERSPEED+). The USB 3.1 standard increases the data signaling rate to 10 Gbit/s in the USB 3.1 Gen2 mode, double that of USB 3.0 (referred to as USB 3.1 Gen1) and reduces line encoding overhead to just 3% by changing the encoding scheme to 128b/132b. The first USB 3.1 implementation demonstrated transfer speeds of 7.2 Gbit/s.

Question: When were the plans to update USB 3.0 to 10 Gbit/s revealed?
Answer: January 2013

Question: What actually happened whenever USB 3.0 was updated?
Answer: The group ended up creating a new USB version

Question: When was USB 3.1 released?
Answer: 31 July 2013

Question: What does the USB 3.1 standard increase?
Answer: the data signaling rate to 10 Gbit/s in the USB 3.1 Gen2 mode
Title: USB

Developed at roughly the same time as the USB 3.1 specification, but distinct from it, the USB Type-C Specification 1.0 was finalized in August 2014 and defines a new small reversible-plug connector for USB devices. The Type-C plug connects to both hosts and devices, replacing various Type-A and Type-B connectors and cables with a standard meant to be future-proof, similar to Apple Lightning and Thunderbolt. The 24-pin double-sided connector provides four power/ground pairs, two differential pairs for USB 2.0 data bus (though only one pair is implemented in a Type-C cable), four pairs for high-speed data bus, two "sideband use" pins, and two configuration pins for cable orientation detection, dedicated biphase mark code (BMC) configuration data channel, and VCONN +5 V power for active cables. Type-A and Type-B adaptors and cables are required for older devices to plug into Type-C hosts. Adapters and cables with a Type-C receptacle are not allowed.[citation needed]

Question: When was the Type-C Specification 1.0 finalized?
Answer: August 2014

Question: What defined a new reversible-plug connector for USB devices?
Answer: USB Type-C Specification 1.0

Question: What does Type-C connect to?
Answer: both hosts and devices

Question: What connector provides four power/ground pairs?
Answer: The 24-pin double-sided connector
Title: USB

Full-featured USB Type-C cables are active, electronically marked cables that contain a chip with an ID function based on the configuration data channel and vendor-defined messages (VDMs) from the USB Power Delivery 2.0 specification. USB Type-C devices also support power currents of 1.5 A and 3.0 A over the 5 V power bus in addition to baseline 900 mA; devices can either negotiate increased USB current through the configuration line, or they can support the full Power Delivery specification using both BMC-coded configuration line and legacy BFSK-coded VBUS line.

Question: Electronically marked cables have a chip that contains what?
Answer: an ID function based on the configuration data channel and vendor-defined messages

Question: What kind of cables does the fully featured USB Type-C contain?
Answer: active, electronically marked cables

Question: What is the shortened version of vendor-defined messages?
Answer: (VDMs)
Title: USB

The design architecture of USB is asymmetrical in its topology, consisting of a host, a multitude of downstream USB ports, and multiple peripheral devices connected in a tiered-star topology. Additional USB hubs may be included in the tiers, allowing branching into a tree structure with up to five tier levels. A USB host may implement multiple host controllers and each host controller may provide one or more USB ports. Up to 127 devices, including hub devices if present, may be connected to a single host controller. USB devices are linked in series through hubs. One hub—built into the host controller—is the root hub.

Question: The design of USB is asymmetrical in what?
Answer: its topology

Question: How many devices may be connected to a host controller?
Answer: 127 devices

Question: How are USB devices linked?
Answer: in series through hubs

Question: What HUB is built into the host controller?
Answer: the root hub

Question: The design of the USB is asymmetrical in its what?
Answer: topology

Question: How many devices can be connected to a host controller?
Answer: Up to 127 devices

Question: What hub is built into the host controller?
Answer: the root hub

Question: A USB host may implement how many host controllers?
Answer: multiple

Question: How many USB ports may a host controller provide?
Answer: one or more USB ports
Title: USB

A physical USB device may consist of several logical sub-devices that are referred to as device functions. A single device may provide several functions, for example, a webcam (video device function) with a built-in microphone (audio device function). This kind of device is called a composite device. An alternative to this is compound device, in which the host assigns each logical device a distinctive address and all logical devices connect to a built-in hub that connects to the physical USB cable.

Question: What are logical sub-devices referred to as?
Answer: device functions

Question: A single device can provide an audio device function such as?
Answer: built-in microphone

Question: A single device can provide a video device function such as?
Answer: a webcam
Title: USB

USB device communication is based on pipes (logical channels). A pipe is a connection from the host controller to a logical entity, found on a device, and named an endpoint. Because pipes correspond 1-to-1 to endpoints, the terms are sometimes used interchangeably. A USB device could have up to 32 endpoints (16 IN, 16 OUT), though it's rare to have so many. An endpoint is defined and numbered by the device during initialization (the period after physical connection called "enumeration") and so is relatively permanent, whereas a pipe may be opened and closed.

Question: What is a pipe?
Answer: a connection from the host controller to a logical entity

Question: A USB connection is based on what?
Answer: pipes (logical channels)

Question: What is a pipe named at?
Answer: an endpoint

Question: Where do pipes correspond?
Answer: 1-to-1 to endpoints

Question: How many endpoints can a USB device have?
Answer: up to 32 endpoints
Title: USB

An endpoint of a pipe is addressable with a tuple (device_address, endpoint_number) as specified in a TOKEN packet that the host sends when it wants to start a data transfer session. If the direction of the data transfer is from the host to the endpoint, an OUT packet (a specialization of a TOKEN packet) having the desired device address and endpoint number is sent by the host. If the direction of the data transfer is from the device to the host, the host sends an IN packet instead. If the destination endpoint is a uni-directional endpoint whose manufacturer's designated direction does not match the TOKEN packet (e.g. the manufacturer's designated direction is IN while the TOKEN packet is an OUT packet), the TOKEN packet is ignored. Otherwise, it is accepted and the data transaction can start. A bi-directional endpoint, on the other hand, accepts both IN and OUT packets.

Question: If the direction of the data transfer is from the device to the host, what does the host send?
Answer: the host sends an IN packet

Question: What does a bi-directional endpoint accept?
Answer: both IN and OUT packets

Question: What is sent if the direction of the data transfer is from host to endpoint?
Answer: an OUT packet
Title: USB

When a USB device is first connected to a USB host, the USB device enumeration process is started. The enumeration starts by sending a reset signal to the USB device. The data rate of the USB device is determined during the reset signaling. After reset, the USB device's information is read by the host and the device is assigned a unique 7-bit address. If the device is supported by the host, the device drivers needed for communicating with the device are loaded and the device is set to a configured state. If the USB host is restarted, the enumeration process is repeated for all connected devices.

Question: What is started when a USB is first connected to a host?
Answer: enumeration process

Question: What id the data rate determined during?
Answer: the reset signaling

Question: When is the device assigned a unique 7-bit address?
Answer: After reset

Question: What does the enumeration process start by doing?
Answer: sending a reset signal to the USB device

Question: What happens whenever a USB host is restarted?
Answer: the enumeration process is repeated for all connected devices.
Title: USB

High-speed USB 2.0 hubs contain devices called transaction translators that convert between high-speed USB 2.0 buses and full and low speed buses. When a high-speed USB 2.0 hub is plugged into a high-speed USB host or hub, it operates in high-speed mode. The USB hub then uses either one transaction translator per hub to create a full/low-speed bus routed to all full and low speed devices on the hub, or uses one transaction translator per port to create an isolated full/low-speed bus per port on the hub.

Question: What do transaction translators do?
Answer: convert between high-speed USB 2.0 buses and full and low speed buses

Question: When does a USB 2.0 hub operate in high speed mode?
Answer: When a high-speed USB 2.0 hub is plugged into a high-speed USB host or hub

Question: What kind of devices do High speed USB 2.0's contain?
Answer: transaction translators
Title: USB

USB implements connections to storage devices using a set of standards called the USB mass storage device class (MSC or UMS). This was at first intended for traditional magnetic and optical drives and has been extended to support flash drives. It has also been extended to support a wide variety of novel devices as many systems can be controlled with the familiar metaphor of file manipulation within directories. The process of making a novel device look like a familiar device is also known as extension. The ability to boot a write-locked SD card with a USB adapter is particularly advantageous for maintaining the integrity and non-corruptible, pristine state of the booting medium.

Question: What do USB's implement connections to?
Answer: storage devices

Question: What are the standards called that implement connections to storage devices?
Answer: the USB mass storage device class (MSC or UMS)

Question: What is the process of making a novel device look like a familiar device?
Answer: extension

Question: Why is the ability to boot write-locked SD cards with a USB adapter advantageous for?
Answer: maintaining the integrity and non-corruptible, pristine state of the booting medium.
Title: USB

Though most computers since mid-2004 can boot from USB mass storage devices, USB is not intended as a primary bus for a computer's internal storage. Buses such as Parallel ATA (PATA or IDE), Serial ATA (SATA), or SCSI fulfill that role in PC class computers. However, USB has one important advantage, in that it is possible to install and remove devices without rebooting the computer (hot-swapping), making it useful for mobile peripherals, including drives of various kinds (given SATA or SCSI devices may or may not support hot-swapping).

Question: Since when can most computers boot from USB mass storage devices?
Answer: since mid-2004

Question: What is USB not intended for?
Answer: a primary bus for a computer's internal storage

Question: What is an important advantage of USB?
Answer: it is possible to install and remove devices without rebooting the computer

Question: Buses such as Parallel ATA fulfill what role in PC computers?
Answer: a computer's internal storage
Title: USB

Firstly conceived and still used today for optical storage devices (CD-RW drives, DVD drives, etc.), several manufacturers offer external portable USB hard disk drives, or empty enclosures for disk drives. These offer performance comparable to internal drives, limited by the current number and types of attached USB devices, and by the upper limit of the USB interface (in practice about 30 MB/s for USB 2.0 and potentially 400 MB/s or more for USB 3.0). These external drives typically include a "translating device" that bridges between a drive's interface to a USB interface port. Functionally, the drive appears to the user much like an internal drive. Other competing standards for external drive connectivity include eSATA, ExpressCard, FireWire (IEEE 1394), and most recently Thunderbolt.

Question: Several manufacturers offer what?
Answer: external portable USB hard disk drives

Question: What do external portable USB hard drive disks offer?
Answer: performance comparable to internal drives

Question: What is the most recent standard for external drive connectivity?
Answer: Thunderbolt

Question: What do the external drives typically include?
Answer: a "translating device"
Title: USB

Media Transfer Protocol (MTP) was designed by Microsoft to give higher-level access to a device's filesystem than USB mass storage, at the level of files rather than disk blocks. It also has optional DRM features. MTP was designed for use with portable media players, but it has since been adopted as the primary storage access protocol of the Android operating system from the version 4.1 Jelly Bean as well as Windows Phone 8 (Windows Phone 7 devices had used the Zune protocol which was an evolution of MTP). The primary reason for this is that MTP does not require exclusive access to the storage device the way UMS does, alleviating potential problems should an Android program request the storage while it is attached to a computer. The main drawback is that MTP is not as well supported outside of Windows operating systems.

Question: Media Transfer Protocol was designed by who?
Answer: Microsoft

Question: Why was Media Transfer Protocol designed?
Answer: to give higher-level access to a device's filesystem

Question: What was MTP originally designed for?
Answer: use with portable media players

Question: Why has MTP become the primary storage access protocol of the Android operating system?
Answer: MTP does not require exclusive access to the storage device the way UMS does
Title: USB

USB mice and keyboards can usually be used with older computers that have PS/2 connectors with the aid of a small USB-to-PS/2 adapter. For mice and keyboards with dual-protocol support, an adaptor that contains no logic circuitry may be used: the hardware in the USB keyboard or mouse is designed to detect whether it is connected to a USB or PS/2 port, and communicate using the appropriate protocol. Converters also exist that connect PS/2 keyboards and mice (usually one of each) to a USB port. These devices present two HID endpoints to the system and use a microcontroller to perform bidirectional data translation between the two standards.

Question: What do older computers have to have in order for USB mice and keyboards to be used?
Answer: PS/2 connectors with the aid of a small USB-to-PS/2 adapter

Question: What is the hardware designed to detect in USB mice and keyboards?
Answer: whether it is connected to a USB or PS/2 port

Question: USB keyboards and mice may communicate using what?
Answer: appropriate protocol

Question: What connects PS/2 keyboards and mice to a USB port?
Answer: Converters

Question: What performs bidirectional data translation between two standards?
Answer: a microcontroller
Title: USB

By design, it is difficult to insert a USB plug into its receptacle incorrectly. The USB specification states that the required USB icon must be embossed on the "topside" of the USB plug, which "...provides easy user recognition and facilitates alignment during the mating process." The specification also shows that the "recommended" "Manufacturer's logo" ("engraved" on the diagram but not specified in the text) is on the opposite side of the USB icon. The specification further states, "The USB Icon is also located adjacent to each receptacle. Receptacles should be oriented to allow the icon on the plug to be visible during the mating process." However, the specification does not consider the height of the device compared to the eye level height of the user, so the side of the cable that is "visible" when mated to a computer on a desk can depend on whether the user is standing or kneeling.

Question: What is difficult to do with a USB plug?
Answer: to insert a USB plug into its receptacle incorrectly

Question: The USB specification states that the required USB icon must be what?
Answer: embossed on the "topside" of the USB plug

Question: How is the USB icon located to each receptacle?
Answer: adjacent

Question: Receptacles should be oriented to allow the icon on the plug to what?
Answer: to be visible during the mating process
Title: USB

The standard connectors were deliberately intended to enforce the directed topology of a USB network: Type-A receptacles on host devices that supply power and Type-B receptacles on target devices that draw power. This prevents users from accidentally connecting two USB power supplies to each other, which could lead to short circuits and dangerously high currents, circuit failures, or even fire. USB does not support cyclic networks and the standard connectors from incompatible USB devices are themselves incompatible.

Question: What do Type-A receptacles do on host devices?
Answer: supply power

Question: What do Type-b receptacles do on target devices?
Answer: draw power

Question: What do the receptacles prevent user from doing?
Answer: from accidentally connecting two USB power supplies to each other

Question: What networks do USB not support?
Answer: cyclic networks
Title: USB

The standard connectors were designed to be robust. Because USB is hot-pluggable, the connectors would be used more frequently, and perhaps with less care, than other connectors. Many previous connector designs were fragile, specifying embedded component pins or other delicate parts that were vulnerable to bending or breaking. The electrical contacts in a USB connector are protected by an adjacent plastic tongue, and the entire connecting assembly is usually protected by an enclosing metal sheath.

Question: Standard connectors were designed to be what?
Answer: robust

Question: Why were standard connectors designed to be so robust?
Answer: the connectors would be used more frequently

Question: What as a drawback of previous connectors?
Answer: Many previous connector designs were fragile

Question: How are the electrical contents of a USB connector protected?
Answer: by an adjacent plastic tongue

Question: How is the entire connecting assembly of a USB connector protected?
Answer: by an enclosing metal sheath
Title: USB

The connector construction always ensures that the external sheath on the plug makes contact with its counterpart in the receptacle before any of the four connectors within make electrical contact. The external metallic sheath is typically connected to system ground, thus dissipating damaging static charges. This enclosure design also provides a degree of protection from electromagnetic interference to the USB signal while it travels through the mated connector pair (the only location when the otherwise twisted data pair travels in parallel). In addition, because of the required sizes of the power and common connections, they are made after the system ground but before the data connections. This type of staged make-break timing allows for electrically safe hot-swapping.

Question: Where is the external metallic sheet connected?
Answer: typically connected to system ground

Question: What provides a degree of protection from interference with the USB signal?
Answer: This enclosure design

Question: This type of stage make-break timing allows for what?
Answer: electrically safe hot-swapping.
Title: USB

The newer micro-USB receptacles are designed for a minimum rated lifetime of 10,000 cycles of insertion and removal between the receptacle and plug, compared to 1,500 for the standard USB and 5,000 for the mini-USB receptacle. Features intended to accomplish include, a locking device was added and the leaf-spring was moved from the jack to the plug, so that the most-stressed part is on the cable side of the connection. This change was made so that the connector on the less expensive cable would bear the most wear instead of the more expensive micro-USB device. However the idea that these changes did in fact make the connector more durable in real world use has been widely disputed, with many contending that they are in fact, much less durable.

Question: What are the newer micro-USB receptacles designed for?
Answer: a minimum rated lifetime of 10,000 cycles of insertion

Question: What is the minimum rated lifetime for the standard USB receptacle?
Answer: 1,500

Question: After a leaf-spring was moved from jack to the plug, the most stressed part was found where?
Answer: on the cable side of the connection

Question: Why was the change made for the USB device?
Answer: so that the connector on the less expensive cable would bear the most wear
Title: USB

The USB standard specifies relatively loose tolerances for compliant USB connectors to minimize physical incompatibilities in connectors from different vendors. To address a weakness present in some other connector standards, the USB specification also defines limits to the size of a connecting device in the area around its plug. This was done to prevent a device from blocking adjacent ports due to the size of the cable strain relief mechanism (usually molding integral with the cable outer insulation) at the connector. Compliant devices must either fit within the size restrictions or support a compliant extension cable that does.

Question: What type of tolerances does the USB standard specify for compliant USB connectors?
Answer: loose tolerances

Question: Why were loose tolerances allowed for compliant USB connectors?
Answer: to minimize physical incompatibilities in connectors from different vendors

Question: How is a weakness addressed in some other connector standards?
Answer: the USB specification also defines limits to the size of a connecting device

Question: Due to size restrictions compliant devices must what?
Answer: fit within the size restrictions or support a compliant extension cable that does