Rockwell Automation Logix5000 Controllers Add-on Instructions Programming Manual - Manual (Page 5)

Table of contents
Studio 5000 environment........................................................................................... 9
Additional resources..................................................................................................... 9
Understanding terminology.................................................................................... 10
Chapter 1
Introduction................................................................................................................ 13
About Add-On Instructions ................................................................................... 13
Components of an Add-On Instruction ............................................................. 14
General information.......................................................................................... 14
Parameters ............................................................................................................ 16
Local tags .............................................................................................................. 16
Data Type............................................................................................................. 17
Logic routine ....................................................................................................... 18
Optional Scan Modes routines ....................................................................... 19
Instruction signature ......................................................................................... 19
Signature history................................................................................................. 20
Change History .................................................................................................. 21
Help ....................................................................................................................... 21
Considerations for Add-On Instructions ........................................................... 22
Instruction functionality .................................................................................. 22
Encapsulation ...................................................................................................... 22
Safety Add-On Instructions ............................................................................ 23
Instruction signature ......................................................................................... 23
Safety instruction signature ............................................................................. 24
Programming languages.................................................................................... 24
Transitional instructions.................................................................................. 25
Instruction size.................................................................................................... 25
Runtime editing.................................................................................................. 26
Nesting Add-On Instructions......................................................................... 26
Routines versus Add-On Instructions .......................................................... 26
Programmatic access to data............................................................................ 28
Unavailable instructions within Add-On Instructions............................ 28
Using GSV and SSV instructions................................................................... 29
Considerations when creating parameters .......................................................... 30
Passing arguments to parameters by reference or by value ...................... 30
Selecting a data type for a parameter ............................................................. 31
Creating an alias parameter for a local tag ................................................... 31
Using a single dimension array as an InOut parameter............................ 31
Determining which parameters to make visible or required................... 32
Preface
Designing Add-On
Instructions
Rock well Automati on Publication 1756- PM010F-EN-P - Oct ober 2014 5