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FireWire Frequently Asked Questions What is FireWire / IEEE-1394? FireWire technology was first invented by Apple Computer in the early 1990s and then was adopted by the IEEE as a standard (IEEE-1394) in 1995. FireWire is a cross-platform high-speed serial technology that can move large amounts of data between computers and peripheral devices. What are the System Requirements for using a FireWire drive?
Can I daisy-chain with FireWire drives or do I need a hub, like with USB? As with SCSI, FireWire is a daisy-chainable technology. All FireWire products (and nearly all FireWire devices) have two FireWire ports and either port can be used for connecting to the host computer or connecting another FireWire device. While FireWire hubs (often referred to as repeaters) are available, they are typically only used when attaching large numbers of devices simultaneously, or with devices that only have one FireWire port (such as digital cameras). Since FireWire can daisy-chain like SCSI, do I need to terminate the last device and keep track of what ID numbers I can use? No, FireWire is a truly user-friendly system. Every FireWire device has its own unique ID code (sort of like a fingerprint -- no two devices have the same code). FireWire does not require the use of terminators. How many FireWire devices can I attach to my computer? The IEEE-1394 standard for FireWire sets a limit of 63 FireWire devices per computer. When connecting directly to your computer, there should be no more than 16 cable lengths between the computer's FireWire port and the last FireWire device. How long can my FireWire cable be? Without using a FireWire Hub or Repeater the maximum recommended cable length is 4 meters between devices. Are FireWire drives hot swappable? Yes, with the following recommendations:
Are there any known conflicts with other FireWire based devices? We are not aware of any hardware conflicts at this time. Can multiple computers share my FireWire drive at the same time? No. The Mac operating system does not have the ability to share the drive between users simultaneously. Can I add multiple FireWire devices? Yes. Simply hook up the device cable to an unused port, either on your computer or the second port at the back of your FireWire drive. Keep in mind some devices such as digital cameras only have one FireWire port, so they must be at the end of a chain. You do not need to worry about device addresses or device termination. There are two rules to keep in mind: first, there is a limit of 63 FireWire devices per computer, and second, there should be no more than 16 cable lengths between the computer and the last FireWire device. Known Limitations and Issues (FireWire): Follow the guidelines listed below for connecting FireWire devices to your computer. If these instructions are not followed, your computer and other FireWire devices may not work correctly. For more information about using and troubleshooting FireWire devices, see the onscreen Help (available in your computer’s Help menu).
Using Multiple FireWire Devices at the Same Time Power Macintosh computers can transfer perfect digital video (DV) on FireWire when no other devices are using the FireWire bus. If you have problems transferring digital video, make certain that no other FireWire devices are being used at the same time. Turning on a DV camera that is already connected may cause a FireWire hard disk to stop working. If this happens, turn off the camera and verify that the hard disk has recovered. Then unplug the FireWire cable from the camera, turn the camera on, and reconnect the FireWire cable to the camera. Check with the hard disk vendor for a possible firmware update to prevent this problem. Using FireWire With a PowerBook If a PowerBook computer with a FireWire CardBus card inserted will not start up, eject the card and restart the computer again. Do not allow a PowerBook computer to sleep while it is receiving digital video. The video input may not continue when the computer wakes up. Do not try to eject a FireWire CardBus card while the card is loaded and live. To eject the card, first shut down the PowerBook to release the driver, and then press the card eject button to remove the card. |