Rockwell Automation 2706-MB1 MESSAGEVIEW 421 SOFTWARE MANUAL - Manual (Page 310)

Glossary G–2
Publication 2706-817
ASCII Input Device – A bar code scanner or other device that
sends alphanumeric data to a MessageView terminal. A terminal
with two ports and firmware that supports ASCII Input may have its
RS-232 port connected to an ASCII Input device. Data input by such
a device is stored as alphanumeric characters in an ASCII entry or
display variable.
ASCII Triggering Device – A device that can trigger messages in a
MessageView terminal via a serial communications link. It reads and
writes data through the terminal’s RS-232 port.
Attribute – In MessageBuilder software, information that
determines how a Message will appear on the MessageView
terminal (e.g., text size), how it interacts with other messages (e.g.
chained), and how it is used by the terminal (e.g. logged in the HE
Stack).
Auxiliary Device – A device connected to the RS-232 port of a
MessageView terminal that is being controlled through its Remote
I/O port by a Logic Controller. An auxiliary device may be an
ASCII Input device such as an AdaptaScan reader, or a Slave
Device such as a Dataliner DL50.
B –
Background Message – A message that is displayed by a
MessageView terminal when no other message has been active for 2
seconds.
Baud – The rate at which data transmission occurs. One baud equals
one Bit per second.
Bit – The smallest unit of information in the binary numbering
system. A bit contains either 0 or 1.
Bitmap – A Graphic image stored as a pattern of dots (or pixels).
Bit Trigger – A Bit location that may be assigned to a Message.
When the Logic Controller sets its bit to 1, the corresponding
message is triggered. An ASCII Triggering application does not
support bit triggers. See also Value Trigger.
Block Transfer – One of the two methods of data transfer used by a
Remote I/O port on a MessageView terminal. See also Direct I/O.
Byte – A sequence of 8 consecutive Bits that are treated as a single
value.