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CICON Simulator Tutorial

Comparing Internal/Local/Global Variables and PLC Data Register
ItemsInternal VariableLocal VariableGlobal VariableData Register
Number of variables that can be registered in a single ST program.500500--
Number of variables that can be registered in a project64,00064,00010,000CPU specifications
Adding arrays/structures (deceleration and usage)-✓✓-
PLC data register allocation (ex. D15)--✓-
Retain setting (maintaining value after power reset (latch))--✓✓
Online Edit modification (add/edit)✓-✓✓
Online Edit - maintaining data--✓✓
Usage in scan program--✓✓
Monitoring in device monitor--✓✓
Monitoring in memory monitor--✓
Usage in special programs (communication, special)---✓
Data backup/recovery function---✓
Use of names in Korean and other non-English languages----

Creating the ST Program​

  1. To create a Structured Text program, right-click in the Project Window and left-click New ST Program.
  • Up to 128 Structured Text programs can be created.

  1. Give the program a name, ID, define its type, and a description. When finished left-click OK.
  • Program Type:
    • Auto: Runs each scan
    • Manual: Called with the STRUN instruction
    • Fixed Cycle: Runs every specified milliseconds

Registering Variables​

Local Variables​

  • Buttons:
    • Edit: Edit the currently selected variable
    • Select All: Select all local variables
    • Deselect: Deselect the variables
    • Copy: Copy the currently selected variable
    • Paste: Paste the currently copied variable
    • Delete: Delete the currently selected variable
    • Recovery: Recover the currently modified variable
    • Cleanup: Organize the variable list
    • Value Write: Write a value to the variable
  • Variable Information:
    • No.: Variable number
    • Var. Name: Name of the variable
    • Var. Class: Type of variable (global, local, internal)
    • Var. Type: Variable data type
    • Device Address: Attached data register address
    • Initial Value: The initial value of the variable
    • Retain: Unavailable for local variables
    • Comment: Variable comments
    • Monitoring: Monitor the values of the variable

Global Variables​

  • Buttons:
    • Edit: Edit the currently selected variable
    • Select All: Select all local variables
    • Deselect: Deselect the variables
    • Copy: Copy the currently selected variable
    • Paste: Paste the currently copied variable
    • Delete: Delete the currently selected variable
    • Recovery: Recover the currently modified variable
    • Cleanup: Organize the variable list
    • Value Write: Write a value to the variable
  • Variable Information:
    • No.: Variable number
    • Var. Name: Name of the variable
    • Var. Class: Type of variable (global, local, internal)
    • Var. Type: Variable data type
    • Device Address: Attached data register address
    • Initial Value: The initial value of the variable
    • Retain: Latch the variable value
    • Comment: Variable comments
    • Monitoring: Monitor the values of the variable

Internal Variables​

Internal variables are used within the Structured Text program logic.

  • How to Use:
    • Variable Name: Data Type; between VAR and END_VAR;.
    • Up to 500 declarations per program.
    • Can be declared anywhere in the ST program. Can only be used after the declaration.
    • Unique names only.
    • Array and Struct types cannot be registered and used.

Compiling & Building​

  1. To compile and build the Structured Text program, left-click Tool and left-click Compile All.

  • If there are any errors, the above messages will appear.

Debugging​

  1. Left-click Parameter and left-click PLC Parameter.

  1. Left-click ST Debugging and check both options.
  • Continuous debugging:
    • Consistently debug or not.
      • When this option is true, there must be a breakpoint before starting a debugging procedure. If it's added while debugging, the breakpoint will not operate.
  • Debugging only open files:
    • Debugging will only occur if the currently display ST program is on the screen.
      • If the program window is opened or closed during the debugging procedure, that program will be included in or excluded from the debugging procedure.

Hot Key​

  • Type F5 on the keyboard to being debugging.

  • While debugging:
    • F6: Debugs until the next step.
    • F9: Adds or removes a breakpoint.
    • Shift + F5: Stops debugging.

Troubleshooting​

Infinite Loop​

When repetitive statements like WHILE or REPEAT are used, the conditional expression must be configured properly. Otherwise, an infinite loop may occur.

If an infinite loop is created in a program, the PLC may malfunction, error, or cause the LED lights to blink.

  1. Move the RUN/STOP switch of the PLC CPU to LOCAL STOP.
  2. Turn OFF and ON the PLC power.
  3. Open CICON and download the modified ST program.
  4. Move the RUN/STOP switch of the PLC CPU to LOCAL RUN or Remote RUN.