KRAMER: SIMPLE CREATIVE TECHNOLOGY
Overview
4
3.2 About FireWire®
FireWire® is a serial bus standard
1
that enables quick universal interfacing
between video and computer hardware items
2
. It is simple to use and
operates independently of the host system, letting you connect more items
than you otherwise could (as a computer only has limited ports available),
and for extended distances. Several can be cascaded to create up to a 63 port
FireWire® Repeater / HUB. FireWire®
s
upports Plug and Play
3
, and
isochronous
4
Many computers have one or more FireWire® ports on the rear panel letting
you quickly attach many devices to your computer. The operating system also
supports FireWire®, enabling quick installation of the device drivers.
Compared to other ways of connecting devices to your computer (including
parallel ports, serial ports and special cards that you install inside the computer's
case), FireWire® devices are simple. Many peripheral devices, such as DV
camcorders, digital still cameras, external hard drives and disk arrays, network
connections, and scanners and printers come in a FireWire® version. To
connect a FireWire® device to a computer is easy (just plug it into the port). If
the device is not yet installed, the operating system auto-detects it and installs
software support for it automatically. If the device has already been installed,
the computer activates it and starts communicating with it. With so many
FireWire® devices on the market today, you easily run out of ports. Use a
FireWire® hub to expand the number of FireWire® ports. The FireWire®
standard supports up to 63 devices and FireWire® hubs are a part of the
standard. You plug the hub into your computer, and then plug your devices (or
other hubs) into the hub. By chaining hubs together, you can build up dozens of
available FireWire® ports on a single computer. A FireWire® hub is like a
network, with bi-directional signals. The standard defines FireWire® as
Peer-to-Peer connection; that is why two devices, or a device and a computer
can talk to each other.
and asynchronous applications.
Note that everything depends on your computer’s software, and the firmware of
the devices. Sometimes a computer can work with many FireWire® devices
simultaneously (like a distributor), sometimes it can work with many devices in
time-sharing mode (like a switcher). But usually it is possible to work
one-to-one. In this case, you have to disconnect all the devices that are
unnecessary at this time and leave only two of them. Since the FireWire® is
hot-plug standard, you can connect/disconnect devices at any time.
1 Originally developed by Apple™ and published as IEEE 1394 by the Institute of Electrical and Electronics Engineers
2 Hardware items include digital cameras, computers, printers, VCRs, CD-ROMs, hard disks, scanners and graphic cards
3 Configures automatically. Whenever a device is added or removed the 1394 bus re-enumerates
4 Video / audio applications require constant transfer rates, which the serial bus provides by supporting isochronous transfers
