FireWire

Originally created by Apple and standardized in 1995 as the specification IEEE 1394 High Performance Serial Bus, FireWire is very similar to Universal Serial Bus (USB). Also known as i.Link or IEEE 1394 is a personal computer (and digital audio/digital video) serial bus interface standard, offering high-speed communications and isochronous real-time data services. FireWire has replaced Parallel SCSI in many applications due to lower implementation costs and a simplified, more adaptable cabling system.  FireWire is most often used to connect digital camcorders, external hard drives, and other devices that can benefit from the high transfer rates supported by the Firewire connection. The iSight camera used for chatting on the Mac connects using a Firewire cable. In addition to connecting peripherals such as camcorders or external hard drives, FireWire can also be used to connect two computers to transfer files..Many computers intended for home or professional audio/video use have built-in FireWire ports including all Macintosh, Dell and Sony computers currently produced. FireWire was also an attractive feature on the Apple iPod for several years, permitting new tracks to be uploaded in a few seconds and also for the battery to be recharged concurrently with one cable. However, Apple has eliminated FireWire support in favor of Universal Serial Bus (USB) 2.0 on its newer iPods due to space constraints and for wider compatibility.

1394 a & 1394 b
There are two format:
 FireWire 400 (1394a) :Transfer rates of up to 400 Mbps and maximum distance between devices of 4.5 meters (cable length)
 FireWire 800 (1394b) : Introduced in 2002, It can transfer rates up to 800 Mbps and maximum distance between devices of 100 meters (cable length).

IEEE 1394 provides two types of data transfer: asynchronous and isochronous. Asynchronous is for traditional load-and-store applications where data transfer can be initiated and an application interrupted as a given length of data arrives in a buffer. Isochronous data transfer ensures that data flows at a pre-set rate so that an application can handle it in a timed way. For multimedia applications, this kind of data transfer reduces the need for buffering and helps ensure a continuous presentation for the viewer.

FireWire is a layered transport system. The IEEE-1394 standard defines three layers: Physical, Link, and Transaction. The Physical layer provides the signals required by the FireWire bus. The Link layer takes the raw data from the Physical layer and formats it into recognizable 1394 packets. The Transaction layer takes the packets from the Link layer and presents them to the application. Link chips provide all link functions as well as a limited number of transaction functions. The remainder of the transaction functions are performed in software.

Firewire has the advantage of being able to transfer power to the device through the same cable that does the data transfer. A disadvantage of Firewire is that cables tend to be more expensive. Like USB, Firewire supports different connector types. The end of the cable that goes into the computer is a 6 Pin cable, while the smaller connector that goes into the camcorder is a 4 Pin cable. To connect two computers, you will need a 6 Pin to 6 Pin cable.

  • FireWire is plug-and-play, so if you connect a new FireWire device to your computer, the operating system auto-detects it and asks for the driver disc. If you’ve already installed the device, the computer activates it and starts talking to it.
  • FireWire devices are hot pluggable, which means they can be connected and disconnected at any time, even with the power on.
  • FireWire 400 and FireWire 800 use different cables that are not compatible with each other., where as the USB has always been good about maintaining backward compatibility.
  • FireWire devices can also create a peer-to-peer network for communicating. i.e they won’t use up system resources like your computer’s memory, it means that they can be used to communicate with each other without a computer at all.
  • The faster 1394b standard is backward-compatible with 1394a.

FireWire is a promising, well-engineered, or well-liked an interface standard boasting faster and more versatile communication than the other new standard, USB.  Its surely a remarkable engineering feat  and looks all set to be in almost every new computer in a couple of years.

Leave a Reply

Your email address will not be published. Required fields are marked *