rpms/dfu-util: USB Device Firmware Upgrade tool". fedoraproject.org. 14 May 2014. Archived from the original on 8 September 2014 . Retrieved 8 September 2014. Universal Charging Solution". GSMA. 17 February 2009. Archived from the original on 30 November 2011 . Retrieved 12 December 2011. The USB1.1 standard specifies that a standard cable can have a maximum length of 5 meters (16ft 5in) with devices operating at full speed (12Mbit/s), and a maximum length of 3 meters (9ft 10in) with devices operating at low speed (1.5Mbit/s). [86] [87] [88]

USB 3.2 Specification Language Usage Guidelines from USB-IF" (PDF). usb.org. 26 February 2019. Archived (PDF) from the original on 3 November 2021 . Retrieved 4 September 2019. Ravencraft, Jeff (19 November 2019). "USB DevDays 2019 – Branding Session" (PDF). USB Implementers Forum (Presentation). p.16. Archived from the original (PDF) on 22 March 2020 . Retrieved 22 March 2020. USB is an industry standard for cables and connectors. Like any technology, it has progressed over time and had various iterations, with significant speed and power improvements. The first version was released in 1996, and the most recent speed upgrade is USB4, released in 2019, though it is not yet widely implemented. As the speeds have increased, so has the physical design of the connectors, and the latest form factor, USB-C, marks a significant improvement on USB-A and USB-B. USB: The BasicsUSB2.0 vs FireWire". Pricenfees. Archived from the original on 16 October 2016 . Retrieved 25 August 2007.

The PCI Express function of USB4 replicates the functionality of previous versions of the Thunderbolt specification. USB4 Version 2.0 from Simulation to Tx, Rx, and Interconnect Test | Signal Integrity Journal". www.signalintegrityjournal.com . Retrieved 22 July 2023. USB device communication is based on pipes (logical channels). A pipe is a connection from the host controller to a logical entity within a device, called an endpoint. Because pipes correspond to endpoints, the terms are sometimes used interchangeably. Each USB device can have up to 32 endpoints (16 in and 16 out), though it is rare to have so many. Endpoints are defined and numbered by the device during initialization (the period after physical connection called "enumeration") and so are relatively permanent, whereas pipes may be opened and closed. Grunin, Lori (4 March 2019). "USB4 Marries Thunderbolt 3 for Faster Speeds and Smarter Transfers". CNET. Archived from the original on 4 March 2019 . Retrieved 4 March 2019. Battery Charging v1.2 Spec and Adopters Agreement". USB.org. Archived from the original on 31 July 2019 . Retrieved 31 July 2019.Contrary to other functions – which use the multiplexing of high-speed links – USB 2.0 over USB-C utilizes its own differential pair of wires. Universal Serial Bus 3.0 Specification" (PDF). 12 November 2008. Archived (PDF) from the original on 6 October 2012 . Retrieved 29 December 2012– via www.gaw.ru. Popularized by Microsoft as Windows Easy Transfer, the Microsoft utility used a special USB bridge cable to transfer personal files and settings from a computer running an earlier version of Windows to a computer running a newer version. In the context of the use of Windows Easy Transfer software, the bridge cable can sometimes be referenced as Easy Transfer cable.

DisplayLink is a technology which allows multiple displays to be connected to a computer via USB. It was introduced around 2006, and before the advent of Alternate Mode over USB-C it was the only way to connect displays via USB. It is a proprietary technology, not standardized by the USB Implementers Forum and typically requires a separate device driver on the computer. USB Device Class Specifications". www.usb.org. Archived from the original on 13 August 2014 . Retrieved 4 May 2018. USB 3.1 - Type-C Host to Host". superuser.com. Archived from the original on 14 October 2021 . Retrieved 21 July 2021. High-speed (HS) uses the same wire pair, but with different electrical conventions. Lower signal voltages of −10 to 10 mV for low and 360 to 440 mV for logical high level, and termination of 45Ω to ground or 90Ω differential to match the data cable impedance. How Thunderbolt Technology Works: Thunderbolt Technology Community". ThunderboltTechnology.net. Archived from the original on 10 February 2014 . Retrieved 22 January 2014.The USB-C, USB-B, and USB-A differences are most obvious in their physical form, but the distinctions run much deeper. USB-C is a more versatile and powerful standard and is set to be the main connector for years to come. However, the range of USB connectors leads to possible confusion. Fundamentals of USB Audio" (PDF). www.xmos.com. XMOS Ltd. 2015 . Retrieved 10 December 2020. Note that Full Speed USB has a much higher intrinsic latency of 2ms USB has had several different form specifications for its connectors. Originally, there were just two USB types, USB-A and USB-B. Now, USB-C is joining the game and now changing everything. USB-A Though USB-C is a newer and better connector that’s about the same size, you will still see micro USB on a ton of devices, ranging from budget Android tablets to Raspberry Pis, micro controllers, digital cameras, power banks and smart home devices. Technically speaking, there is both micro USB Type-A and Type-B, but you’re only likely to see Type-B. USB Type-C Battery Charging v1.2 Spec and Adopters Agreement" (ZIP). USB Implementers Forum. 7 March 2012. Archived from the original on 6 October 2014 . Retrieved 13 May 2021.

The USB 3.0 specification introduced an A-to-A cross-over cable without power for connecting two PCs. These are not meant for data transfer but are aimed at diagnostic uses. Some cables have the same connector at both ends and are named accordingly—for example, a USB Type-C to USB Type-C cable. Interested in USB charging for the office?Because of the previous confusing naming schemes, USB-IF decided to change it once again. As of 2 September 2022, marketing names follow the syntax "USB xGbps", where x is the speed of transfer in Gb/s. [44] Overview of the updated names and logos can be seen in the adjacent table. Devices that draw no more than one unit are said to be low-power devices. All devices must act as low-power devices when starting out as unconfigured. For USB devices up to USB2.0 a unit load is 100mA (or 500mW), while USB3.0 defines a unit load as 150mA (750mW). Full-Featured USB-C Fabrics can support low-power devices with a unit load of 250mA (or 1250mW). A stream pipe is a uni-directional pipe connected to a uni-directional endpoint that transfers data using an isochronous, [54] interrupt, or bulk transfer: September 2022 naming scheme [ edit ] An overview of USB naming scheme that was put in place in September 2022.