Acomdata E5 External Hard Drives User Manual

Acomdata E5 External Hard Drives User Manual Manual pdf 9 page image

– 14 – – 15 –Peer-to-peer architectureFireWire devices are host-independent, meaning datatransmissions between FireWire devices on the same buscan take place without the need for input from the hostcomputer. This lack of dependence on the host is one of thereasons FireWire devices are on average faster than USB 2.0devices in routine day-to-day use, even though the ratedmaximum data transfer is lower than that for USB 2.0.Cable length up to 4.5 mStandard FireWire 400 cables use 6-pin connectors at bothends. FireWire 800 cables use 9-pin connectors. Cables with4-pin connectors are also available for connecting FireWiredevices to laptop/notebook computers and other devicesthat have 4-pin ports.On-bus power up to 45 wattsFireWire can supply up to 45 W of electrical power, making itpossible to use many low-power-consumption devices with-out a dedicated electrical connection. (FireWire cables with4-pin connectors cannot transmit electrical power.) Whena device is powered via FireWire, power is delivered onlywhen actually needed.Plug & PlayYou do not need to install drivers, assign unique ID numbers,or connect terminators.Hot PluggableFireWire devices can be connected to or disconnected fromthe computer while the computer is running. Always dis-mount a hard drive before turning off and disconnecting it.AcomData E5 FeaturesExploredIf you have a PushButton Drive, refer to the PushButtonBackup User’s Guide for a description of PushButton Backup.FireWire(FireWire-equipped Drives only)FireWire is a serial data input/output technology developedby Apple Computer and Texas Instruments. The first FireWirestandard was approved by the Institute of Electrical andElectronic 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 datatransfers. Isochronous mode provides guaranteed transmis-sion of data at defined intervals; it’s used when delayedor out-of-order data frames are unacceptable, such as forcapturing digital video. In asynchronous mode the intervalsbetween transmissions can vary, and data can be resent ifmissed. Asynchronous mode is typically used for routine datatransfers.Supports up to 63 devicesFireWire devices can be linked in a daisy-chain, where thedevices are connected to each other in series. A hub is onlyrequired when a very large number of devices will share thesame FireWire bus. With the use of FireWire hubs, up to 63devices can be linked on a single FireWire bus.