HP C2858A, Руководство по обслуживанию

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G-2 Glossary
IEEE 488-1978 interface A parallel
interface standardized by Electronic Industries
Association Standard 488-1978.
initialize To set plotter conditions to known
default values.
interface Anything (a cable, for example)
used to join components of a computer system
so they function in a compatible and
coordinated fashion. Also, standards which
allow systems to connect with each other
(e.g., HP-IB, RS-232-C).
I/O error A data transmission error
between a computer and a peripheral.
Examples of I/O errors are mismatched
interface conditions, such as baud rate and
parity.
menu Messages and options displayed on
the plotter’s front-panel display.
nest A group of compatible plots arranged
next to each other horizontally/vertically to
save media when plotted.
A collection of interconnected,
individually controlled computers, together
with the hardware and software used to
connect them. A network allows users to
share data and peripheral devices such as
printers and storage media, to exchange
electronic mail, and so on.
overflow To exceed the capacity of a
buffer’s storage space. When a buffer
overflows, the excess data is lost.
palette A set of sixteen pens (numbered 0
through 15) for which width and % shading
are defined from the plotter’s front panel.
parallel interface An interface type in
which a separate wire is used for each data bit
in a byte or word and all bits are transferred
simultaneously. HP-IB and Centronics are
parallel interfaces.
parity An error-checking method for
information transfer between a computer and
a peripheral device. Parity is used to check the
accuracy of binary data.
peripheral (device) A device separate from,
but used with, a computer. For example, a disc
drive, printer, or plotter.
queue Order in which plot data is received.
raster 1. A matrix of dots, or pixels, where
each pixel is defined by a bit. A bit that is
“on” will print a dot on the paper. A bit that is
“off” will leave the area blank. 2. A method
for defining a plot directly in terms of the
pixels rather than as vectors.
repeatability A measure of how closely a
device can return a pen to the previously
plotted point.
resolution A measure of image sharpness
expressed as a number of lines per unit length.
When referring to plotters, addressable
resolution means the smallest move the plotter
can make programmatically.
RS-232-C interface A serial interface
standardized by the Electronic Industries
Association Standard RS-232-C.
serial interface A serial interface uses a
single data line to transfer data bits
sequentially between devices. RS-232-C is a
serial interface.