Rockwell Automation 2706-M1 MESSAGEVIEW 421 HARDWARE MANUAL User Manual
Page 77

4–17
Running Applications
Publication 2706–816
Field 5: Line Number Byte
The Line Number Byte indicates the display line on which the
message will appear. The Line Number Byte is automatically
embedded in the slave packet based on the message’s Line attribute.
Line Attribute Selected
Line Number Embedded
1
1
2
2
3
3
4
4
Any
1 to 4, depending on the line where the Master
device displays the message
All
50
The “All” Line attribute (50) is used with the Ctrl-C Optional
Control Byte to clear all lines on the slave device.
The Line Number Byte function depends on the slave device and its
functions. Consult the slave device’s user manual for the line
configurations it supports.
Field 6: Carriage Return
The Carriage Return (decimal 13) indicates the end of a message
packet. It is embedded at the end of the Slave Packet automatically.
Embedded variables in a slaved message
If a message sent to a MessageView 421D Slave Device terminal
contains:
•
embedded ISA graphic symbols, each graphic symbol must be
preceded by a Ctrl-G (See Field 2: ASCII Text)
•
entry variables (numeric or ASCII), these variables are not
supported.
•
display variables (numeric, ASCII or a date/time), the message
needs to be sent continuously to the MessageView 421D Slave
Device in order to have the variables updated.
Note: If a message contains display variables and is sent to the
slave device on a continuous basis, only the variables are updated,
not the text portion of the message.