Firewire basics, Firewire vs. usb, Firewire bus – Universal Audio UAD POWERED PLUG-INS ver.6.1 User Manual
Page 137: Bus power, Firewire 400 vs. 800, It with uad-2 satellite. for details, see
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UAD Powered Plug-Ins Manual
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Chapter 11: UAD-2 Satellite
FireWire Basics
FireWire (also known as “IEEE 1394” and “i.Link”) is a high-speed serial data
interconnection protocol that is used to transfer digital information between
devices. FireWire is commonly used to interconnect computer systems to hard
drives, audio interfaces, and digital camcorders.
A complete discussion of FireWire is beyond the scope of this manual, but
some of the main points and how they apply to UAD-2 Satellite are covered
below.
FireWire vs. USB
FireWire is considered superior to USB for audio purposes because it does
not rely on the host processor to manage low-level data housekeeping
(among other reasons). FireWire typically outperforms USB at the same rated
speeds.
FireWire Bus
FireWire devices are connected to a FireWire “bus” which is comprised of all
devices in the serial data stream (
,
, and
). The FireWire specification supports up to 63 peripherals per
FireWire bus.
Many FireWire devices and host computers have more than one FireWire
connector, but these connectors almost always attach to the same FireWire
bus (most computers do not have more than one FireWire bus). It is possible
to add another FireWire bus to a computer, typically by adding a
PCIe-to-FireWire or ExpressCard-to-FireWire adapter card.
Bus Power
Some FireWire devices can be “bus powered” which means the device de-
rives its operating electricity from the FireWire bus itself without a power sup-
ply of its own. See
“FireWire Bus Power” on page 144
Important:
UAD-2 Satellite cannot be bus powered and it does not supply
bus power from its FireWire ports to other devices.
FireWire 400 vs.
800
The most common FireWire devices are available in two speeds: FireWire
400 (IEEE 1394a), which supports transfer speeds up to 400 megabits per
second, and FireWire 800 (IEEE 1394b), which supports up to 800 megabits
per second. It’s usually possible to determine the speed of the FireWire device
by the type of FireWire connector it uses (see
below).