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Rockwell Automation Publication 1756-RM010C-EN-P - August 2018
Appendix A
Align LINT Members on 8-byte Boundaries
To correct Produce/Consume errors that are caused by UDT alignment
changes, modify the tag structures in both projects so that they match.
• Produce/Consume with Status requires an exact match of the UDT
definition (including the name of the UDT definition).
• Produce/Consume without Status requires the Size of the UDT to
match.
We recommend that you copy and paste the UDT definition from one project
to the other to cover both of these cases. Use the Data Type editor to check the
Data Type Size in both projects:
Figure 1 - Data Type Editor
If the data type size is different between the two projects, modify the UDT to
produce the same internal data structure.
The following sample UDT illustrates how the 8-byte allocation rule and the
8-byte alignment rule cause a UDT to have another size.
Figure 2 - UDT Sample - Needs Additional Memory Allocation and Alignment
Summary of Contents for ControlLogix 5570 series
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