Rockwell Automation 2706-F11J_F11JC_F21J_F21JC DL50 INSTALLATION MANUAL - Manual (Page 126)

A–B
Glossary
Glossary–1
A
ACK
An abbreviated term for Positive
Acknowledgement. A control code
that indicates that the previous
transmission block was received
correctly.
address
A character or a group of characters
that identifies a particular part of
memory, or some source or
destination for a data message.
Also, refers to a device or an item of
data by its address.
ampere
A unit of current flow.
ASCII
The character set and code described
in American National Standard Code
for Information Interchange, ANSI
X3.4Ć1977. Each ASCII character is
encoded with 8Ćbits including parity
check.
B
baud
A rate at which a transmission
occurs, where one baud equals one
bit per second.
binary
A base two numbering system.
bit
The smallest unit of information in
the binary numbering system. A bit
is represented by the digits 0 and 1.
buffer
A temporary storage area for
messages or other data.
byte
A unit of data that contains 8 bits.
C
checksum
A means of verifying the validity of
transmitted data.
controller, programmable
Refer to programmable controller.
D
default value
A value that is provided for the user by
the DL50. It can be set by the user by
means of DIP switches.
digit
A single numeric character.
DIP switch
An acronym for Dual InĆline Package
switch. A DIP switch is a circuit board
mounted switch comprised of one or
more individual selector switches.
DTE
An acronym for Data Terminal
Equipment. A DTE receives and
processes transmitted data. The DL50
is considered a DTE device as are
most terminals.
E
electrical noise
Electromagnetic interference. Any
electromagnetic disturbance that
interrupts, obstructs, or otherwise
impairs the performance of
electronic equipment.