LATEST QUESTION: How many hard drives can be daisy chained together using FireWire 800? Answer
OVERVIEW...
What is IEEE-1394 (FireWire)? Answer
What will 1394 do? Answer
What is the future of 1394? Answer
QUESTIONS ABOUT HOW FIREWIRE WORKS...
Is there anything I should know about using Windows 7 with my FireWire devices? Answer
If I get a new Mac that has FireWire 800, will I have to replace all my external FireWire 400 drives? Answer
What can I do if my FireWire drives stopped working after I upgraded to Mac OS X 10.5.3? Answer
Can I connect and disconnect 1394 devices without turning the power off? Answer
What kind of products can talk to each other over 1394? Answer
What if my computer does not already have a 1394 connector? Answer
Do I need a computer to make 1394 work? Answer
Do I need to upgrade my BIOS when I add a 1394 card? Answer
QUESTIONS ABOUT FIREWIRE APPLICATIONS
How do I file a complaint with the FCC if the 1394 port on my cable box is not working? Answer
What can I use FireWire for? Answer
Why is 1394 good for video editing? Answer
What about computer peripherals, like my external hard drive or printer? Answer
QUESTIONS ABOUT THE NAME...
Does 1394 have a formal name? Answer
What is FireWire®? Answer
What is i.LINK®? Answer
QUESTIONS RELATING TO OTHER TECHNOLOGIES....
Why another interface? Answer
What is the difference betwen 1394 and Universal Serial Bus (USB)? Answer
USB2 is 480 Mbps – isn’t this faster than FireWire 400? Answer
Isn't FireWire just used for DV cameras, whereas USB can be used for
a wide range of peripherals? Answer
How many hard drives can be daisy chained together using FireWire 800?
In principle you can chain 62 FireWire 800 hard drives to a computer that has FireWire 800. This is possible because IEEE 1394b does not use the "gap" timing from IEEE 1394-1995 and IEEE 1394a, so a pure 1394b bus does not have a limit on the hop count. Instead, the only limit is the 63 node maximum: 62 drives plus one host.
In practice, achieving 62 chained drives will depend on several conditions:
1. There must be no FireWire 400 (or slower) devices connected. Connecting such a device will force the old-style "gap" timing, which will limit the chain length to about 16 devices. It's OK if some drives or the host has empty FireWire 400 sockets, as long as they are not connected.
2. There must be enough power for all of the drives. Most or all of the drives will need their own AC power connection, instead of using power from FireWire.
3. The host computer software might not be able to support 62 simultaneous drives.
4. The FireWire bus must not contain any "hidden" nodes. For example, the Apple Mac Pro tower computer has an extra FireWire 800 hub connected to the front panel FireWire ports. If the host is a Mac Pro, at most 61 drives could be chained to that host. (61 drives plus 2 host nodes = 63 node limit)
5. Not all FireWire 800 silicon is compatible with such long chains; some chips will have a lower limit. Check with your drive vendor to find out how long of a chain is supported. TOP
Is there anything I should know about using Windows 7 with my FireWire devices?
Windows 7 offers FireWire users a number of benefits over earlier versions of Windows. Microsoft has also released an important patch to Win7 related to 1394. You can get more information on Microsoft's support pages. TOP
If I get a new Mac that has FireWire 800, will I have to replace all my external FireWire drives?
FireWire 800 is completely compatible with older FireWire devices. You just need a widely-available and inexpensive cable or adapter that has a FireWire 800 connector on one end, and the appropriate (6-pin or 4-pin) FireWire 400 connector on the other end. If you daisy chain your devices, be sure to put your FireWire 800 devices closest to your FireWire 800 port to maintain their speed. TOP
What if my FireWire drives aren't working after an upgrade to OS X 10.5.3?
First, make sure that you're using the latest firmware for your device. Check the manufacturer's website for updates and install them; this will usually fix any issues. You can also try reinstalling the Mac OS X 10.5.3 Combo Update. TOP
What
is FireWire?
FireWire, also known as IEEE1394
or i.LINK, is an industry standard for a high-speed, scalable, flexible, easy to use, low-cost digital interface that integrates the worlds of consumer electronics and personal computers. It was first conceived by Apple Computer and then developed by the 1394 Working Group within the Institute of Electrical and Electronics Engineers (IEEE). The IEEE 1394 standard defines its interface as:
• Digital. 1394 does not require the conversion of digital data into analog. That means better signal integrity.
• Physically small. 1394 provides a thin serial cable which, through the use of repeaters, can be extended to 100 meters or more over CAT5, firber optic, and even coax cables.
• Easy to use. 1394 eliminates the need to load special drivers or perform complicated set-ups.
• Hot pluggable. 1394 enables devices to be added and removed while equipment is turned on and does not require computers to be "rebooted."
• Scalable. 1394 supports up to 64 devices on a single network.
• Flexible. 1394 lets you connect devices to each other by simply daisy chaining them together. No need for hubs or switches. It also supports branching, loops and other topologies, which reduces cabling complexity. It also allows for "peer-to-peer" connections — the ability for consumer electronic devices to be connected without the need for a computer.
• Fast. 1394 supports guaranteed delivery of time-critical data at multiple speeds, including 100, 200 400, and 800 Megabits per second, with 1600 and 3200 coming soon, over a single continuous cable or "bus." This enables high-quality audio and video applications while reducing the cost of the interface. TOP
What will 1394 do?
1394 is required on all HD cable set top boxes in the United States. Additionally, it is the preferred computer attachment for professional and high-end digital cameras and digital video applications. IEEE 1394 has been accepted as the standard digital interface by the Digital VCR Conference (DVC), and the European Digital Video Broadcasters (DVB) have endorsed IEEE 1394 as their digital television interface as well. It is included in 80% of all new PCs providing up to 4x faster access to external storage than USB 2.0. TOP
Does 1394 have a formal name?
The name FireWire™, an Apple Trademark, is the most common name for it. The other commonly used name is i.LINK, a Sony Corporation trademark. The name 1394 actually comes from the IEEE 1394 specification which defines the technical characteristics of the interface. TOP
What is FireWire®?
FireWire is an Apple trademark for the IEEE 1394 standard. TOP
What is i.LINK®?
i.LINK is a Sony trademark for the IEEE 1394 standard. TOP
Why another interface?
Several key trends have led to an increased need for FireWire:
• Consumer electronics and computers are converging.
• With the emergence of multimedia, more and more data is video and audio. FireWire provides guaranteed Quality of Service, which means that this time sensitive data will arrive at the TV regardless of whatever else is on the network. Few other networks can make such a guarantee.
• Valuable content such as movies require content security, the ability to protect unauthorized distribution of the content such as over the Internet or by making copies. FireWire uses DTCP, which has been approved for use by all of the major Hollywood studios to transfer content over the network.
• The need and desire for high speed, peer-to-peer computing is growing. An example is the ability to connect a digital camera directly to a printer to print photographs. 1394 does not require the use of a computer. TOP
What kind of products can talk to each other over 1394?
1394 is for connecting digital electronic devices such as DV camcorders and D-VCRs, digital still cameras, digital set-top boxes, digital TV sets and many computer peripheral devices such as external hard drives that have a 1394 connector.
Additionally, the automotive industry has developed a standard using FireWire for connecting DVD players, navigation devices, digital cameras, and audio systems due to its high speed and reliability. TOP
What if my computer does not already have a 1394 connector?
No problem. Several companies offer relatively inexpensive 1394 adapters, also referred to as 1394 "add-on" or "adapter" cards. These cards are actually printed circuit boards that can be easily inserted into a slot (usually a PCI slot) inside your computer. The cards include one or more 1394 connectors and, once inserted, enable your computer to communicate with 1394-enabled consumer electronic and peripheral devices. TOP
Can I connect and disconnect 1394 devices without turning the power off?
Yes. 1394 is "hot pluggable." That means when you plug in a new device, the 1394 "bus" automatically recognizes it. Similarly, when a device is disconnected, 1394 automatically reconfigures itself. In fact, the standard 1394 cable provides up to 1.5 amps of DC power to keep remote devices "aware," even when they are turned off. TOP
Do I need a computer to make 1394 work?
No. You do not need a computer to take advantage of 1394. A 1394-enabled Blu-ray recorder for example, can be connected directly to a 1394-enabled camcorder, TV set, stereo receiver, amplifier or other home theater component without the need for a computer. TOP
Why is 1394 good for video editing?
In the world of video editing, 1394-enabled cameras remove the need for costly analog-to-digital converters and frame buffers, otherwise known as "video capture" cards. 1394 also improves upon existing interfaces such as USB, traditionally used for external storage of digital video. 1394 provides higher speed, lower cost, and is more user-friendly than existing video interfaces. It also is far more efficient than USB in terms of the amount of processing power required. USB requires that the system processor service the network directly slowing down other applications such as video and audio editing. FireWire places a negligible burden on the processor leaving it free to run your application. TOP
What about computer peripherals, like my external hard drive or printer?
1394 has the bandwidth capacity to replace and consolidate most other peripheral connection/communication methods in use today. Hot plugging, power sourcing and dynamic reconfiguration make 1394 a user-friendly alternative to today's interconnects. These features make "plugging in" computer peripherals as easy as plugging in a home appliance. FireWire shines most brightly when used for external storage devices, where its throughput and sustained read/write speeds outshine USB 2.0. TOP
What is the difference between 1394 and Universal Serial Bus (USB)?
Almost everyone who works with these technologies considers 1394 a complement to USB, since it offers much higher speeds (up to 1.2 Gigabit) and was designed primarily with video/audio/data transfer in mind. USB is ideal for, and was designed for, inexpensive computer peripherals that do not have a need for higher speeds and the guaranteed Quality of Service provided by FireWire. Also USB is a Master/Slave network requiring a PC or other device to serve as the Master. FireWire is a true peer-to-peer network with no requirement for a master device. Many new PCs now include ports for both of these standards. TOP
What is the future of 1394?
High Definition TVs are becoming commonplace. However, most HD sources such as Blu-ray DVD players, cable and IPTV set top boxes and satellite receivers, use HDMI to connect to your DTV. HDMI cannot be networked and only operates over short distances making it nearly impossible to share your expensive HD sources with TVs in other rooms. FireWire has the ability to operate over the same wiring used by Ethernet (UTP CAT5 cable) as well as fiber optical cable and even the same coax wire used by your cable and satellite TV services. It provides the necessary speed and reliability (guaranteed QoS) to distribute HD content throughout your home. It also supports DTCP content protection, which has been approved by all of the major Hollywood studios to protect their most valuable property – HD movies and TV programming. No other networking technology today can do this. Therefore as HD becomes the norm, FireWire will become the network of choice. It is already required on all HD cable set top boxes and is the connection of choice for professionals who work with HD video and audio.
1394 has the potential to transform the consumer electronics and computer industries by making a vast array of new applications possible. Once an electronic device becomes 1394-enabled, it can reliably and securely share data with other devices and be controlled by a computer. If the computer is connected to the Internet, that control is extended to locations worldwide. TOP
What
can I use FireWire for?
FireWire is used for a wide range
of applications, including:
a) Storage - FireWire provides a very fast and flexible means of connecting
external storage and RAID systems to a PC.
b) Audio - FireWire is the bus of choice for connecting Pro and Semi-Pro
audio equipment to PC applications. It is used for multi-channel recording
& playback with guaranteed Quality of Service (QoS).
c) AV streaming - The vast majority of camcorders have a FireWire port
(also known as 1394 or i-Link) for connecting and transferring video
data to a PC. The FCC mandates the incorporation of a FireWire port
into all digital Set Top Boxes in the US, so future PCs could stream
contents to and from STBs.
d) Networking - PCs can be networked together directly using FireWire,
currently up to S400. Bridging to an Ethernet network is straightforward.
e) Bus-Powered Peripherals- FireWire has a much larger bus power capability
than USB, so PC peripherals such as 5.1 surround speaker system or storage
devices that draw their power from the bus directly without a need for
a power brick. FireWire bus provides up to 45W (30Volts, 1.5A) for connected
devices. This is adequate to drive a wide range of PC peripherals including
some hard drives. TOP
USB2
is 480 Mbps – isn’t this faster than FireWire 400?
480 Mbits per second is the raw
bus rate for USB2 and NOT the rate at which
data transfer can be achieved. There is a much higher overhead involved
in USB2
data transfer and typical actual data rates for an external HDD from a
Win XP
platform are:
| |
Headline |
Actual
Read |
Actual
Write |
Efficiency
(Average) |
| USB 2.0 |
480 |
264 |
208 |
49% |
| 1394a |
400 |
332 |
264 |
75% |
| 1394b |
800 |
712* |
496* |
76% |
Data Rates using
Oxford Semiconductor’s OXUF924
All data rates in Mbits/sec
* Striped RAID solution
Many current USB2 devices will only
run at ‘Full speed’, which is a very slow 12 Mbps.
FireWire is available now at 800
Mbps. The actual data throughput for FireWire 800 based RAID systems is
limited by the disk performance and not by the FireWire bus. FireWire
1600 and FireWire 3200 are in development. TOP
Isn’t
FireWire just used for DV cameras, whereas USB can be used for a
wide range of peripherals?
There are millions of devices shipped
each year with FireWire:
• 11 million Desktop PCs (which is roughly 10% of total PC market) are shipped annually with FireWire.
• 36 million Laptop PCs shipped annually have FireWire
• 6 million external storage devices have a FireWire interface
• 14 million Digital Camcorders have FireWire TOP
Do I need to upgrade my BIOS when I add a 1394 card?
No - for any PC or Mac system with a PCI or CardBus slot, you can add a 1394
card and it will be automatically detected and supported by the operating
system. On Windows you may be asked to install a driver, which is included in
standard Windows distributions.
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