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45-532: IEEE 1394 is an interface standard for a serial bus for high-speed communications and isochronous real-time data transfer. It was developed in the late 1980s and early 1990s by Apple in cooperation with a number of companies, primarily Sony and Panasonic . It is most commonly known by the name FireWire (Apple), though other brand names exist such as i.LINK (Sony), and Lynx ( Texas Instruments ). The copper cable used in its most common implementation can be up to 4.5 metres (15 ft) long. Power and data

90-572: A FireWire hub is used) computer networks . Specifically, RFC 2734 specifies how to run IPv4 over the FireWire interface, and RFC 3146 specifies how to run IPv6 . Mac OS X, Linux , and FreeBSD include support for networking over FireWire. Windows 95 , Windows 98 , Windows Me , Windows XP and Windows Server 2003 include native support for IEEE 1394 networking. Windows 2000 does not have native support but may work with third party drivers. A network can be set up between two computers using

135-467: A Sony camera being the only notable user. A project named IEEE P1394d was formed by the IEEE on March 9, 2009 to add single-mode fiber as an additional transport medium to FireWire. The project was withdrawn in 2013. Other future iterations of FireWire were expected to increase speed to 6.4 Gbit/s and additional connectors such as the small multimedia interface. Full support for IEEE 1394a and 1394b

180-476: A build-to-order option on some models since 1997), and most Apple Macintosh computers manufactured in the years 2000 through 2011 included FireWire ports. However, in February 2011 Apple introduced the first commercially available computer with Thunderbolt . Apple released its last computers with FireWire in 2012. By 2014, Thunderbolt had become a standard feature across Apple's entire line of computers (later with

225-445: A certain percentage to isochronous data and the rest to asynchronous data. In IEEE 1394, 80% of the bus is reserved for isochronous cycles, leaving asynchronous data with a minimum of 20% of the bus. FireWire uses Data/Strobe encoding (D/S encoding). In D/S encoding, two non-return-to-zero (NRZ) signals are used to transmit the data with high reliability. The NRZ signal sent is fed with the clock signal through an XOR gate , creating

270-519: A device can pull about 7 to 8 watts from the port; however, the voltage varies significantly from different devices. Voltage is specified as unregulated and should nominally be about 25 volts (range 24 to 30). Apple's implementation on laptops is typically related to battery power and can be as low as 9 V. An amendment, IEEE 1394a, was released in 2000, which clarified and improved the original specification. It added support for asynchronous streaming , quicker bus reconfiguration, packet concatenation , and

315-416: A major technical improvement, namely new port specification that provides 800 Mbit/s over the same 8P8C (Ethernet) connectors with Category 5e cable , which is specified in IEEE 802.3 clause 40 ( gigabit Ethernet over copper twisted pair ) along with a corresponding automatic negotiation that allows the same port to connect to either IEEE Std 1394 or IEEE 802.3 ( Ethernet ) devices. In December 2007,

360-642: A military and aerospace databus network in those vehicles. AS5643 is utilized by several large programs, including the F-35 Lightning II , the X-47B UCAV aircraft, AGM-154 weapon and JPSS-1 polar satellite for NOAA. AS5643 combines existing 1394-2008 features like looped topology with additional features like transformer isolation and time synchronization, to create deterministic double and triple fault-tolerant data bus networks. FireWire can be used for ad hoc (terminals only, no routers except where

405-449: A number of PC desktops, and other small FireWire devices. The 4-conductor connector is fully data-compatible with 6-conductor alpha interfaces but lacks power connectors. IEEE 1394b-2002 introduced FireWire 800 (Apple's name for the 9-conductor S800 bilingual version of the IEEE 1394b standard). This specification added a new encoding scheme termed beta mode which allowed compliant devices to operate at 786.432 Mbit/s full-duplex . It

450-556: A power-saving suspend mode . IEEE 1394a offers a couple of advantages over the original IEEE 1394–1995. 1394a is capable of arbitration accelerations, allowing the bus to accelerate arbitration cycles to improve efficiency. It also allows for arbitrated short bus reset, in which a node can be added or dropped without causing a big drop in isochronous transmission. 1394a also standardized the 4-conductor alpha connector developed by Sony and trademarked as i.LINK , already widely in use on consumer devices such as camcorders, most PC laptops,

495-488: A single standard FireWire cable, or by multiple computers through use of a hub. This is similar to Ethernet networks with the major differences being transfer speed, conductor length, and the fact that standard FireWire cables can be used for point-to-point communication. On December 4, 2004, Microsoft announced that it would discontinue support for IP networking over the FireWire interface in all future versions of Microsoft Windows . Consequently, support for this feature

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540-407: A strobe signal. This strobe is then put through another XOR gate along with the data signal to reconstruct the clock. This in turn acts as the bus's phase-locked loop for synchronization purposes. The process of the bus deciding which node gets to transmit data at what time is known as arbitration . Each arbitration round lasts about 125 microseconds. During the round, the root node (device nearest

585-523: A superseding standard, IEEE 1394-2008 . The features individually added give a good history on the development path. The original release of IEEE 1394-1995 specified what is now known as FireWire 400. It can transfer data between devices at 100, 200, or 400  Mbit/s half-duplex data rates (the actual transfer rates are 98.304, 196.608, and 393.216 Mbit/s, i.e., 12.288, 24.576 and 49.152 MB/s respectively). These different transfer modes are commonly referred to as S100, S200, and S400. Cable length

630-549: Is Apple's name for the IEEE 1394 High Speed Serial Bus. Its development was initiated by Apple in 1986, and developed by the IEEE P1394 Working Group, largely driven by contributions from Sony (102 patents), Apple (58 patents), Panasonic (46 patents), and Philips (43 patents), in addition to contributions made by engineers from LG Electronics , Toshiba , Hitachi , Canon , INMOS /SGS Thomson (now STMicroelectronics ), and Texas Instruments . IEEE 1394

675-510: Is a serial bus architecture for high-speed data transfer, serial meaning that information is transferred one bit at a time. Parallel buses utilize a number of different physical connections, and as such are usually more costly and typically heavier. IEEE 1394 fully supports both isochronous and asynchronous applications. Apple intended FireWire to be a serial replacement for the parallel SCSI bus, while providing connectivity for digital audio and video equipment. Apple's development began in

720-478: Is absent from Windows Vista and later Windows releases. Microsoft rewrote their 1394 driver in Windows 7 but networking support for FireWire is not present. Unibrain offers free FireWire networking drivers for Windows called ubCore, which support Windows Vista and later versions. Interface standard An interface standard may include operational characteristics and acceptable levels of performance. In

765-732: Is available for Microsoft Windows , FreeBSD , Linux , Apple Mac OS 8.6 through macOS 14 Sonoma and NetBSD . In Windows XP, a degradation in performance of 1394 devices may have occurred with installation of Service Pack 2. This was resolved in Hotfix 885222 and in SP3 . Some FireWire hardware manufacturers also provide custom device drivers that replace the Microsoft OHCI host adapter driver stack, enabling S800-capable devices to run at full 800 Mbit/s transfer rates on older versions of Windows (XP SP2 w/o Hotfix 885222) and Windows Vista. At

810-402: Is backwards compatible with the slower rates and 6-conductor alpha connectors of FireWire 400. However, while the IEEE 1394a and IEEE 1394b standards are compatible, FireWire 800's connector, referred to as a beta connector, is different from FireWire 400's alpha connectors, making legacy cables incompatible. A bilingual cable allows the connection of older devices to the newer port. In 2003, Apple

855-462: Is carried over this cable, allowing devices with moderate power requirements to operate without a separate power supply. FireWire is also available in Cat 5 and optical fiber versions. The 1394 interface is comparable to USB . USB was developed subsequently and gained much greater market share. USB requires a host controller whereas IEEE 1394 is cooperatively managed by the connected devices. FireWire

900-442: Is designed to support plug and play and hot swapping . The copper cable it uses in its most common implementation can be up to 4.5 metres (15 ft) long and is more flexible than most parallel SCSI cables. In its six-conductor or nine-conductor variations, it can supply up to 45 watts of power per port at up to 30 volts, allowing moderate-consumption devices to operate without a separate power supply. FireWire devices implement

945-538: Is limited to 4.5 metres (14.8 ft), although up to 16 cables can be daisy chained using active repeaters, e.g. external hubs or the internal hubs that are often present in FireWire equipment. The S400 standard limits any configuration's maximum cable length to 72 metres (236 ft). The 6-conductor connector is commonly found on desktop computers and can supply the connected device with power. The 6-conductor powered connector, now referred to as an alpha connector, adds power output to support external devices. Typically

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990-415: Is said to require use of 261 issued international patents held by ten corporations. Use of these patents requires licensing; use without license generally constitutes patent infringement . Companies holding IEEE 1394 IP formed a patent pool with MPEG LA, LLC as the license administrator, to whom they licensed patents. MPEG LA sublicenses these patents to providers of equipment implementing IEEE 1394. Under

1035-493: Is the library source for all 1394 documentation and standards available. FireWire can connect up to 63 peripherals in a tree or daisy-chain topology (as opposed to Parallel SCSI's electrical bus topology). It allows peer-to-peer device communication — such as communication between a scanner and a printer — to take place without using system memory or the CPU . FireWire also supports multiple host controllers per bus. It

1080-887: The 1394 Trade Association announced that products would be available before the end of 2008 using the S1600 and S3200 modes that, for the most part, had already been defined in 1394b and were further clarified in IEEE Std. 1394–2008. The 1.572864 Gbit/s and 3.145728 Gbit/s devices use the same 9-conductor beta connectors as the existing FireWire 800 and are fully compatible with existing S400 and S800 devices. It competes with USB 3.0 . S1600 (Symwave) and S3200 (Dap Technology) development units have been made, however because of FPGA technology DapTechnology targeted S1600 implementations first with S3200 not becoming commercially available until 2012. Steve Jobs declared FireWire dead in 2008. As of 2012, there were few S1600 devices released, with

1125-529: The FCC issued an order that permitted set-top boxes to include IP-based interfaces in place of FireWire. While both technologies provide similar end results, there are fundamental differences between USB and FireWire. USB requires the presence of a host controller, typically a PC, which connects point to point with the USB device. This allows for simpler (and lower-cost) peripherals, at the cost of lowered functionality of

1170-458: The ISO/IEC 13213 configuration ROM model for device configuration and identification, to provide plug-and-play capability. All FireWire devices are identified by an IEEE EUI-64 unique identifier in addition to well-known codes indicating the type of device and the protocols it supports. FireWire devices are organized at the bus in a tree topology. Each device has a unique self-ID. One of

1215-623: The actual 1394 Patent Portfolio License upon request to MPEG LA. MPEG LA does not provide assurance of protection to licensees beyond its own patents. At least one formerly licensed patent is known to have been removed from the pool, and other hardware patents exist that reference IEEE 1394. The 1394 High Performance Serial Bus Trade Association (the 1394 TA ) was formed to aid the marketing of IEEE 1394. Its bylaws prohibit dealing with intellectual property issues. The 1394 Trade Association operates on an individual no cost membership basis to further enhancements to 1394 standards. The Trade Association also

1260-502: The bus network, whereas, until USB 3.0, USB featured only one. This means that FireWire can have communication in both directions at the same time (full-duplex), whereas USB communication prior to 3.0 can only occur in one direction at any one time (half-duplex). While USB 2.0 expanded into the fully backwards-compatible USB 3.0 and 3.1 (using the same main connector type), FireWire used a different connector between 400 and 800 implementations. IDB-1394 Customer Convenience Port (CCP)

1305-517: The bus. Intelligent hubs are required to connect multiple USB devices to a single USB host controller. By contrast, FireWire is essentially a peer-to-peer network (where any device may serve as the host or client), allowing multiple devices to be connected on one bus. The FireWire host interface supports DMA and memory-mapped devices, allowing data transfers to happen without loading the host CPU with interrupts and buffer-copy operations. Additionally, FireWire features two data buses for each segment of

1350-443: The cables, while 1394b added a data encoding scheme called 8b/10b referred to as beta mode . Beta mode is based on 8b/10b (from Gigabit Ethernet , also used for many other protocols). 8b/10b encoding involves expanding an 8-bit data word into 10 bits, with the extra bits after the 5th and 8th data bits. The partitioned data is sent through a Running Disparity calculator function. The Running Disparity calculator attempts to keep

1395-419: The coding scheme is to support the arbitration for bus access and general bus control. This is possible due to the surplus symbols afforded by the 8b/10b expansion. (While 8-bit symbols can encode a maximum of 256 values, 10-bit symbols permit the encoding of up to 1024.) Symbols invalid for the current state of the receiving PHY indicate data errors. IEEE 1394c-2006 was published on June 8, 2007. It provided

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1440-457: The devices. FireWire is capable of both asynchronous and isochronous transfer methods at once. Isochronous data transfers are transfers for devices that require continuous, guaranteed bandwidth. In an aircraft, for instance, isochronous devices include control of the rudder , mouse operations and data from pressure sensors outside the aircraft. All these elements require constant, uninterrupted bandwidth. To support both elements, FireWire dedicates

1485-537: The exception of the 12-inch MacBook introduced in 2015, which featured only a sole USB-C port), effectively becoming the spiritual successor to FireWire in the Apple ecosystem. Apple's last products with FireWire, the Thunderbolt Display and 2012 13-inch MacBook Pro , were discontinued in 2016. Apple previously sold a Thunderbolt to FireWire Adapter, which provided one FireWire 800 port. A separate adapter

1530-644: The late 1980s, later presented to the IEEE, and was completed in January 1995. In 2007, IEEE 1394 was a composite of four documents: the original IEEE Std. 1394–1995, the IEEE Std. 1394a-2000 amendment, the IEEE Std. 1394b-2002 amendment, and the IEEE Std. 1394c-2006 amendment. On June 12, 2008, all these amendments as well as errata and some technical updates were incorporated into a superseding standard, IEEE Std. 1394–2008. Apple first included onboard FireWire in some of its 1999 Macintosh models (though it had been

1575-507: The military community, interface standards permit command and control functions to be performed using communication and computer systems. There are many interface standards between analog telephone central office equipment and customer-premises equipment . Single voice paths generally include analog audio connections, either a two-wire circuit or four-wire circuit plus signaling paths to indicate call progress and status information, such as ringing, answer supervision , etc. Some of

1620-413: The nodes is elected root node and always has the highest ID. The self-IDs are assigned during the self-ID process, which happens after each bus resets. The order in which the self-IDs are assigned is equivalent to traversing the tree depth-first , post-order. FireWire is capable of safely operating critical systems due to the way multiple devices interact with the bus and how the bus allocates bandwidth to

1665-457: The number of 1s transmitted equal to 0s, thereby assuring a DC-balanced signal. Then, the different partitions are sent through a 5b/6b encoder for the 5-bit partition and a 3b/4b encoder for the 3-bit partition. This gives the packet the ability to have at least two 1s, ensuring synchronization of the PLL at the receiving end to the correct bit boundaries for reliable transfer. An additional function of

1710-399: The processor) sends a cycle start packet. All nodes requiring data transfer respond, with the closest node winning. After the node is finished, the remaining nodes take turns in order. This repeats until all the devices have used their portion of the 125 microseconds, with isochronous transfers having priority. The previous standards and its three published amendments are now incorporated into

1755-434: The time of its release, Microsoft Windows Vista supported only 1394a, with assurances that 1394b support would come in the next service pack. Service Pack 1 for Microsoft Windows Vista has since been released, however the addition of 1394b support is not mentioned anywhere in the release documentation. The 1394 bus driver was rewritten for Windows 7 to provide support for higher speeds and alternative media. In Linux, support

1800-436: The typical patent pool license, a royalty of US$ 0.25 per unit is payable by the manufacturer upon the manufacture of each 1394 finished product; no royalties are payable by users. The last of the patents, MY 120654 by Sony, expired on November 30, 2020. As of November 30, 2020, the following are patent holders of the IEEE 1394 standard, as listed in the patent pool managed by MPEG LA . A person or company may review

1845-454: Was also popular in industrial systems for machine vision and professional audio systems. Many users preferred it over the more common USB 2.0 for its then greater effective speed and power distribution capabilities. Benchmarks show that the sustained data transfer rates are higher for FireWire than for USB 2.0, but lower than USB 3.0 . Results are marked on Apple Mac OS X but more varied on Microsoft Windows . Implementation of IEEE 1394

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1890-693: Was originally provided by libraw1394 making direct communication between user space and IEEE 1394 buses. Subsequently, a new kernel driver stack, nicknamed JuJu, has been implemented. Under FCC Code 47 CFR 76.640 section 4, subsections 1 and 2, Cable TV providers (in the US, with digital systems) must, upon request of a customer, have provided a high-definition capable cable box with a functional FireWire interface. This applied only to customers leasing high-definition capable cable boxes from their cable provider after April 1, 2004. The interface can be used to display or record Cable TV, including HDTV programming. In June 2010,

1935-535: Was required to use it with Thunderbolt 3. Sony's implementation of the system, i.LINK , used a smaller connector with only four signal conductors, omitting the two conductors that provide power for devices in favor of a separate power connector. This style was later added into the 1394a amendment. This port is sometimes labeled S100 or S400 to indicate speed in Mbit/s. The system was commonly used to connect data storage devices and DV (digital video) cameras, but

1980-625: Was the automotive version of the 1394 standard. IEEE 1394 was the High-Definition Audio-Video Network Alliance (HANA) standard connection interface for A/V (audio/visual) component communication and control. HANA was dissolved in September 2009 and the 1394 Trade Association assumed control of all HANA-generated intellectual property. SAE Aerospace standard AS5643 originally released in 2004 and reaffirmed in 2013 establishes IEEE-1394 standards as

2025-558: Was the first to introduce commercial products with the new connector, including a new model of the Power Mac G4 and a 17" PowerBook G4 . The full IEEE 1394b specification supports data rates up to 3200 Mbit/s (i.e., 400 MB/s) over beta-mode or optical connections up to 100 metres (330 ft) in length. Standard category 5e cable supports 100 metres (330 ft) at S100. The original 1394 and 1394a standards used data/strobe (D/S) encoding , now known as alpha mode , with

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