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Peer-to-peer architecture
FireWire devices are host-independent, meaning data
transmissions between FireWire devices on the same bus
can take place without the need for input from the host
computer. This lack of dependence on the host is one of the
reasons FireWire devices are on average faster than USB 2.0
devices in routine day-to-day use, even though the rated
maximum data transfer is lower than that for USB 2.0.
Cable length up to 4.5 m
Standard FireWire 400 cables use 6-pin connectors at both
ends. FireWire 800 cables use 9-pin connectors. Cables with
4-pin connectors are also available for connecting FireWire
devices to laptop/notebook computers and other devices
that have 4-pin ports.
On-bus power up to 45 watts
FireWire can supply up to 45 W of electrical power, making it
possible to use many low-power-consumption devices with-
out a dedicated electrical connection. (FireWire cables with
4-pin connectors cannot transmit electrical power.) When
a device is powered via FireWire, power is delivered only
when actually needed.
Plug & Play
You do not need to install drivers, assign unique ID numbers,
or connect terminators.
Hot Pluggable
FireWire devices can be connected to or disconnected from
the computer while the computer is running. Always dis-
mount a hard drive before turning off and disconnecting it.
AcomData E5 Features
Explored
If you have a PushButton Drive, refer to the PushButton
Backup User’s Guide for a description of PushButton Backup.
FireWire
(FireWire-equipped Drives only)
FireWire is a serial data input/output technology developed
by Apple Computer and Texas Instruments. The first FireWire
standard was approved by the Institute of Electrical and
Electronic Engineers (IEEE) in 1995.
Data transfers at up to 800 Mbps (100 MB/s)
FireWire 400 can transmit data at up to 400 Mbps (50 MB/s).
FireWire 800 can transmit data at up to 800 Mbps (100 MB/s).
FireWire supports both
isochronous
and
asynchronous
data
transfers. Isochronous mode provides guaranteed transmis-
sion of data at defined intervals; it’s used when delayed
or out-of-order data frames are unacceptable, such as for
capturing digital video. In asynchronous mode the intervals
between transmissions can vary, and data can be resent if
missed. Asynchronous mode is typically used for routine data
transfers.
Supports up to 63 devices
FireWire devices can be linked in a daisy-chain, where the
devices are connected to each other in series. A hub is only
required when a very large number of devices will share the
same FireWire bus. With the use of FireWire hubs, up to 63
devices can be linked on a single FireWire bus.
