Rockwell Automation 2755-DM9, -DM9E High Speed Decoder - Manual (Page 156)

A–B
Glossary
G–1
A
ACK
An abbreviated term for Positive
Acknowledgement. A control code
that indicates that the previous
transmission block was received.
address
A character or group of characters
that identifies a register, a particular
part of storage, or some other data
source or destination. To refer to a
device or an item of data by its
address.
AIM
Acronym for Automatic
Identification Manufacturers. A
trade group that sets standards for
bar code equipment.
alphanumeric or alphameric
The character set which contains
letters, digits, and other characters
such as punctuation marks.
ASCII
The character set and code described
in American National Standard Code
for Information Interchange, ANSI
X3.4–1977. Each ASCII character is
encoded with 8–bits including parity
check.
AUX Port
Serial port that can be connected to
an ASCII terminal to monitor and
program the decoder.
B
bar
The dark element of a printed
symbol.
bar code
An arrangement of rectangular bars
and spaces in a predetermined
pattern.
bar code density
The number of characters which can
be represented in a lineal inch.
bar code label
A label that carries a bar code(s) and
is suitable to be affixed to an article.
bit
An acronym for Binary Digit. The
smallest unit of information in the
binary numbering system.
Represented by the digits 0 and 1.
byte
A unit of data that contains 8 bits.
C
capture count
The number of identical and valid
scans which must be deoded before a
valid read occurrs.
character
A single group of bars and spaces
representing an individual number,
letter or punctuation mark. A
graphic shape representing a letter,
number or symbol.
check digit
A digit included within a symbol
whose value is based mathematically
on other characters included in the
symbol. It is used to mathematically
check the accuracy of the read.
code
A set of unambiguous rules
specifying the way in which data
may be represented. See bar code.