PLC Programming

What is What in CoDeSys
Calling an action:
An action is called up with . or ..
Regard the notation in FBD (see example below) ! If it is required to call up the action within its own
block, one just uses the name of the action in the text editors and in the graphic form the function
block call up without instance information.
Examples for calls of the above described action from another POU:
Declaration for all examples:
PROGRAM PLC_PRG
VAR
Inst : Counter;
END_VAR
Call of action 'Reset' in another POU, which is programmed in IL:
CAL Inst.Reset(In := FALSE)
LD Inst.out
ST ERG
Call of action 'Reset' in another POU, which is programmed in ST:
Inst.Reset(In := FALSE);
Erg := Inst.out;
Call of action 'Reset' in another POU, which is programmed in FBD:
Resources
Libraries
Notes: Actions play an important role in blocks in sequential function charts, see Sequential Function Chart.
The IEC standard does not recognise actions other than actions of the sequential function chart.
You need the resources for configuring and organizing your project and for tracing variable values:
• Global Variables which can be used throughout the project or network
• Library manager for adding libraries to the project
• Log for recording the actions during an online session
• PLC Configuration for configuring your hardware
• Task Configuration for guiding your program through tasks
• Watch and Receipt Manager for displaying variable values and setting default variable values
• Target system settings for selection and if necessary final configuration of the target system
Depending on the target system and on the target settings made in CoDeSys the following resources
also might be available in your project:
• Sampling Trace for graphic display of variable values
• Parameter Manager for data exchange with other controllers in a network
• PLC-Browser as controller monitor
• Tools – availability depending on target – for calling external tool programs from within CoDeSys
You can include in your project a series of libraries whose POUs, data types, and global variables you
can use just like user-defined variables. The libraries standard.lib and util.lib are standard parts of the
program and are always at your disposal.
CoDeSys V2.3 2-7