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Rockwell Automation Publication 1789-UM002K-EN-P - January 2015
Chapter 6
Execute External Routines
Fault Conditions
This table describes major fault conditions.
Execution
The JXR can be synchronous or asynchronous depending on the implementation
of the DLL. The code in the DLL also determines how to respond to scan status,
rung-condition-in status, and rung-condition-out status.
Type Checking
This table describes the type checking that occurs between the Logix Designer
application and the external routine for the parameters that they pass.
For more details on creating a DLL by using Visual Studio, see
A major fault occurs if
Fault type
Fault code
•
An exception occurs in the external routine DLL.
•
The DLL could not be loaded.
•
The entry point was not found in the DLL.
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Data Type
C++ Type
Passing Method
Type Checking
Arrays
BOOL
Bool
By reference
By value
Strong type checking
By reference
Array sizes are not checked, but the size
information is passed through the control
structure
INT
Short
DINT
Long
Int
SINT
Char
REAL
Float
User-defined structure
Structure
By reference
Weak type checking
The check determines whether a structure is
being passed to a structure parameter. Data types
and sizes are not checked.
By reference
Array sizes are not checked, but the size
information is passed through the control
structure