What is FireWire?

What is FireWire?

What is FireWire? FireWire is the brand name of Apple Inc. for the IEEE 1394 interface. Another name for this FireWire is i.Link, which is the Sony brand name. FireWire is also called IEEE 1394, however the standard for the 1934 additionally defines a backplane interface. It is a serial bus interface standard for personal computers, as well as for digital audio and for digital video, that offers high speed communications and isochronous real time data services. Because of lower implementation costs plus a simplified more adaptable cabling system, FireWire has replaced Parallel SCSI in various applications. HANA, or the High Definition Audio-Video Network Alliance, has adopted IEEE 1394 as the standard connection interface for audio/video component control and communication. FireWire also comes in a coaxial, wireless, and fiber optic versions using the isochronous protocols.

FireWire4 is Apple Inc.'s brand name for the IEEE 1394 High Speed Serial Bus. It was started by Apple and created by the IEEE P1394 Working Group, which was mostly driven by contributions from Apple, although engineers from Texas Instruments, Digital Equipment Corporation, Sony, IBM, and St Microelectronics (was INMOS/SGS Thomson ) also made major contributions. FireWire was intended by Apple to become a parallel SCSI bus serial replacement while providing digital audio and video equipment connectivity as well. The development by Apple was finished in 1995. Currently in 2007, IEEE 1394 is a composite of three separate documents. These are the original 1995 IEEE standard 1394, the 2000 amendment to the original document, the IEEE Std 1394a, and the 2002 amendment to the original document, the IEEE Std 1394b. There is a third amendment planned, 1394c, which will provide support for 800 Mbit per second transmitted over 100m of unshielded twisted pair Category 5 cable, but that has not been published yet, but will be available soon.

i.Link is the brand name for the implementation of the system by Sony. This system only uses four signal pins, getting rid of the two pins that provide power to the device and replacing them with a separate power connector on all i.Link products by Sony.

The IEEE 1394 High Speed Serial Bus system is usually used for the connection of digital video cameras and data storage devices, but also has become popular in professional audio systems and industrial systems for machine vision. This system is used in place of the more common USB system because of it's faster effective speed, higher power-distribution capabilities, and due to the fact that it does not need a computer host. What is even more important is the fact that FireWire has full utilization of all SCSI capabilities and has higher sustained data transfers when compared to USB2, especially on the Apple Mac OS X. The results on Windows is more varied, probably because the USB2 is the answer to FireWire by Intel on Windows machines.

FireWire has not replaced USB in the low end computer peripherals mass market where a major constraint is the cost of the product due to the more costly hardware that is needed to implement it and the royalty fee demanded by Apple Inc and the other patent holders.

This FireWire connection has been in almost all the modern digital camcorders ever since 1995. Some computers that are intended for home or for professional audio/video use have built-in FireWire ports. This includes all Dell computers, except for the Inspiron 1501, Latitude 131L, and the Dimension 8300 series, all Apple computers, and all Sony laptop computers currently produced. FireWire is also readily available on retail motherboards alongside USB for do it yourself personal computers.. FireWire was used with the first models of Apple's iPod, but later i pod models got rid of FireWire support in favor of USB because of space constraints and the need for wider compatibility.

FireWire has the capability to connect up to 63 peripherals in an acyclic topology, compared to the Parallel SCSI's Electrical bus topology. It will also allow for peer to peer device communication, like the communication between a printer and a scanner, to happen without using the CPU or the system memory. It will also support multiple hosts per bus. FireWire is designed for the support of plug and play and hot swapping. The FireWire six wire cable has more flexibility than most most Parallel SCSI cables, and can also supply up to 45 watts of power per each port at up to 30 volts, allowing medium-consumption devices to operate without using a separate power supply. However, the i.Link normally leaves out the power wiring of the cables in favor of a separate power adaptor for each device.