Omron SYSMAC CS1W-RPT01 Operation Manual page 190

Checking Data Link Status
Processing Data Only when Operation Is Normal Using the IL-ILC and JMP-JME Instructions
Writing 0000 in the Data Link Area when Errors Occur
Note
Perform processing only when operation is normal by creating a program
based on program blocks that process data for each node with the IL-ILC and
JMP-JME programs.
Node A Data Link
Normal Operation Flag
Node B Data Link
Normal Operation Flag
Node C Data Link
Normal Operation Flag
"Data Link Normal Operating Flags" can be created using the programming
described in 5-4-5 Error Detection Program Example .
When data links are not operating normally, write 0000 to the data link area of
the node with the error to stop other data being received.
As an example, the following example shows how to write 0000 in the data link
area of node 2 (D00100 to D00120) using the BSET (block set) instruction
when an error occurs at node 2.
■ Data Link Example: Communications Error at Node 2
Node 1
Node 1
Node 2 X
Node 62
■ Example of Programming for Node 1 to Handle Communications Errors at
Node 2
Node 2 Data Link
Normal Operation Flag
Insert the above programming at the start of the program.
"Data Link Normal Operating Flags" can be created using the programming
described in 5-4-5 Error Detection Program Example .
1. If an error occurs and 0000 is written to the Data Link Area occurs for an
unstable transmission path (i.e., one that repeatedly alternates between
communications errors and normal operation), the normal data will be fre-
IL
ILC
IL
ILC
IL
ILC
Node 2
Node 1
Node 2
Node 62
BSET
0000 is written continuously
in node 2's area (D00100 to
# 0 0 0 0
D00120) until node 2's flag
D00100
turns ON.
D00120
Section 5-4
Node A data processing
Node B data processing
Node C data processing
Node 62
Node 1
Node 2
Node 62
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