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ICC
Figure 80: Reading and Writing via MSG Instructions
Figure 81 shows the
configuration details of the
example
fc_wr_connection MSG
instruction. Note that the
chosen “Message Type” is
“CIP Data Table Write”,
and that this instruction
will be writing 21 16-bit
values.
Note that when writing data via explicit messaging, use caution to ensure that the
commanded addresses are not also simultaneously being commanded in the
background via I/O messaging. Indeterminate behavior can occur if MSG
instructions and background I/O data transfers are both writing to the same
addresses. In other words, if the I/O messaging example procedure detailed in
section 11.7.3.2 has already been implemented, and the same program is now
being modified to implement explicit messaging, then it is recommended to inhibit
the target module by selecting the “Inhibit Module” checkbox in the Connection
tab of the Module Properties dialog.
Figure 81: MSG Configuration for Writing
