104 Rockwell Automation Publication 1756-RM100F-EN-P - October 2018
Chapter 5 Standard Application Conversion
I/O Data Manipulation
When you address Compact 5000 I/O modules in a Logix Designer
application project, many instructions that previously permitted a direct
reference to an entire input or output word now report an invalid data type
error.
You can encounter the invalid data type error when you migrate programs that
are written for older Logix 5000 controllers and I/O platforms to programs
written for 5580 and 5380 controllers with Compact 5000 I/O modules. The
error is the result of the new structure that was implemented with the
Compact 5000 I/O platform, as described in the previous section. The I/O
data is grouped by “channel” by default, and no longer shown at the word level
as an INT or DINT data type.
To get around this error a “Packed Data” type can be selected at the I/O
configuration screen when adding the I/O module in the Logix Designer
application. You can use a Copy File (COP) instruction or Synchronous
Copy File (CPS) instruction to move the packed data into an interim tag. You
can then use the tag in the user program for word-level manipulation.
We recommend that you only use CPS instructions when you need data
integrity with copying produce/consume tag and I/O tag data. Overuse of the
CPS instruction can have unintended consequences on task execution and
program scan time.
When encountered with this error in converting your programs, follow closely
the guidelines in Knowledgebase article "790954 - Invalid data type error when
using 5069 I/O modules" for a suitable migration path forward.
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