Omron ns series Operation Manual page 39

4. Press the I/O Cmt Button to switch the I/O comments display to three lines, one line,
or not at all.
• To display an I/O comment file that was created using the I/O Comment Extracting
Note
Tool, use the same project file as the source for the CXT file and as the source of the
program transferred to the PLC for which the Ladder Monitor is to be used. If the
source project file is not the same, I/O comments and addresses may not
correspond correctly.
• To display an I/O comment file that was created using the I/O Comment Extracting
Tool, the I/O comment file for the Ladder Monitor must be saved in the Memory Card
(or, for version-2 NS-series PTs and NSJ Controllers, it must be saved in the PT in
advance).
• If there is an I/O comment file with the same name in both the PT and the Memory
Card when using a version-2 NS-series PT or NSJ Controller, the I/O comment file in
the PT will be used.
• Do not register more than one symbol for the same address in the symbol tables. If
two or more symbols with the same address are registered, an unintended I/O
comment may be displayed for the address displayed by the Ladder Monitor (i.e., a
different I/O comment for the same address).
• I/O comment data that has been read is saved in the PT. Once the data has been
Note
read it does not have to be read from the PLC.
• I/O comment data that has been read is saved in the PT under the file names "G-host
name.ioc" and "L-host name.ioc." If there is already a file in the PT with the same file
name, it will be overwritten.
• Use only alphanumeric characters (A to Z, a to z, and 0 to 9), underscores (_), and
dollar signs ($) in host names. If any other characters are used in host names, you
will not be able to read I/O comments from the PLC.
• In the following cases a message will be displayed to confirm whether I/O comments
are to be read from the PLC when the Ladder Monitor is started. If Yes is selected,
I/O comments will be read from the PLC.
• When I/O comments have not been read from the PLC (when there is no
comment file in the PT or on the Memory Card)
• When the PLC symbol table has been changed
• I/O comments cannot be read from the PLC if the symbol table is not downloaded to
the PLC. In that case, I/O comments created using the I/O Comment Extracting Tool
can be displayed.
• The Ladder Monitor searches the PLC Memory Card, EM file memory, and comment
memory in order, and reads the I/O comment data from the first symbol table that is
found.
• If the PLC symbol table is cleared after the Ladder Monitor reads I/O comments from
the PLC, the next time the Ladder Monitor is started, a message will be displayed to
check whether the previously created I/O comment file is to be deleted.
Ladder Monitor When Connecting PT to PLC through a Serial Port
Connect one of the serial ports, port A or B, on the PT to the PLC and enable
communications in 1:N NT Link communications mode.
2-1 Starting the Ladder Monitor
37