I-Bus 0818D, User Manual

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Appendix 2 – Glossary of Terms
0818D User’s Guide A2-3
L
LED: Light Emitting Diode. Long-lasting light emitters usually used
as indicators.
load board: A board having specific power load characteristics
which are typically used for testing.
P
parallel port: I/O connector used to hook up a printer or other
parallel interface device. The parallel port is usually a 25-pin female
DB25 connector.
PCI(Peripheral Component Interconnect): A PC expansion bus
standard maintained by the PCI Special Interest Group, a consortium
of industrial partners.
port: Ports are used to connect peripheral devices such as external
drives and printers to your computer.
power good: A logic signal used to indicate that DC output from a
PC power supply has stabilized. The power good line switches from
0 to +5 volts within one tenth to one half second after the power
supply reaches normal voltage levels. Whenever output voltage is
out of normal operating range for any reason, the power good signal
goes back to zero.
power ON/diagnostic LED: The LED located on the front control
panel that indicates that power is applied to the computer.
power supply: Electrical system that converts AC or DC source
power into the lower level DC power required by the computer
circuitry. In a personal computer, 3.3, +5, -5, +12 and -12 voltages
are generated by the system power supply.
power switch: The power switch turns main source power ON/OFF
to the computer. It is usually located on the front computer panel or
the rear panel near the input power cable.
R
RAID (Redundant Arrays of Independent Disks): A storage
technology using an array of two or more disks to redundantly store