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Firewire plug & play capabilities, Firewire hot-plug and screw-lock precautions, Chapter – ALLIED Vision Technologies Stingray F-504 User Manual

Page 42

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FireWire

STINGRAY Technical Manual V4.4.4

41

FireWire Plug & play capabilities

FireWire devices implement the ISO/IEC 13213 configuration ROM model for
device configuration and identification, to provide plug & play capability. All
FireWire devices are identified by an IEEE EUI-64 unique identifier (an exten-
sion of the 48-bit Ethernet MAC address format) in addition to well-known
codes indicating the type of device and protocols it supports. For further
details read Chapter

Configuration of the camera

on page 257.

FireWire hot-plug and screw-lock precautions

Caution

Hot-plug precautions

Although FireWire devices can theoretically be hot-
plugged without powering down equipment, we
strongly recommend turning the computer power off,
before connecting a digital camera
to it via a FireWire
cable.

Static electricity or slight plug misalignment during
insertion may short-circuit and damage components.

The physical ports may be damaged by excessive ESD
(electrostatic discharge), when connected under pow-
ered conditions. It is good practice to ensure proper
grounding of computer case and camera case to the
same ground potential, before plugging the camera
cable into the port of the computer. This ensures that
no excessive difference of electrical potential exists
between computer and camera.

As mentioned earlier, it is very important not to exceed
the inrush energy of 18 mJoule in 3 ms. (This means
that a device, when powered via 12 V bus power must
NEVER draw more than 1.5 A, but only 0.5 A in the first
3 ms, assuming constant flow of current.)

Higher inrush current over longer periods may damage
the physical interface chip of the camera and/or the
phy chip in your PC
. Whereas inrush current is not a
problem for one Stingray camera, daisy chaining multi-
ple cameras or supplying bus power via (optional)
HIROSE power out to circuitry with unknown inrush cur-
rents needs careful design considerations to be on the
safe side.

Screw-lock precautions

Also, all AVT 1394b camera and cables have industrial
screw-lock fasteners
, to insure a tight electrical con-
nection that is resistant to vibration and gravity.

We strongly recommend using only 1394b adapter
cards with screw-locks.