Rockwell Automation 5370 Color CVIM Communications Manual - Manual (Page 217)

Configurable Vision Input Module
Bulletin 5370 Color CVIM
Glossary
G–2
floating point
A system of representing numerical
quantities with a variable number of
places in which the location of the
point does not remain fixed.
G
gray scale
In monochromatic displays,
variations in brightness level used to
enhance the contrast among the
displayed features.
H
handshaking
Two–way communication between
two devices to effect a data transfer.
Handshaking operations are based on
a Data–Ready/Data–Received signal
scheme that assures orderly data
transfer.
hex
Abbreviated form of the word
hexadecimal.
hexadecimal
A base 16 numbering system.
hexadecimal numbering system
A numbering system using the
equivalent of the decimal number 16
as a base. Because only a single
character is allowed for each
absolute value, the hexadecimal
numbering system uses the 10
symbols of the decimal system for
values 0 through 9, and the first six
letters of the alphabet to represent
values 10 through 15 (a through F).
The positional significance of the
hexadecimal symbols is based upon
the progression of powers of 16. The
highest number that can be
represented in the units position is
15.
I
Image
A photographic picture, e.g., as being
picked up by a TV camera.
Mathematically, an image can be
described by a function of 2
variables f(x,y), usually defined over
a rectangular region. X and y are the
region coordinates, and f(x,y)
represents the gray scale value of the
point (x,y) in the region.
I/O
Acronym for Input/ Output.
L
left justified
A field of numbers (decimal, binary,
etc) with no zeros or spaces to the
left.
lightpen
A hand held photosensitive input
device used to designate a location
on a display screen.
N
NAK
An abbreviated term for Negative
Acknowledgment. A control code
that indicates the previous
transmission block was not received
correctly.