ii)
If "Cache Connections" is enabled
(checked), the connection remains
open after transmission. If disabled
(unchecked), the connection is
opened before and closed after every
transmission. For efficiency, it is
recommended to enable "Cache
Connections".
e) Click "OK" to close the MSG
Configuration dialog. At this stage,
MainRoutine should look like Figure 61.
5) Assign a tag to the XIO element.
a) Double-click on the XIO element located
to the left of the MSG block. In the drop-
down box, double-click on the
"connection.EN" field. Refer to Figure 62.
This configuration causes the MSG
instruction to automatically retrigger itself
when it completes. While this is
acceptable for the purposes of this
example, it can produce high network
utilization. In actual practice, it may be
desirable to incorporate additional logic
PROTOCOL-SPECIFIC INFORMATION
Figure 60: Setting the Communication Path
Figure 61: MainRoutine
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