Omron CS1-H Series, Operation Manual

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Instance Specifications Section 2-2
Note For details, refer to 2-5 Precautions for Instructions with Operands Specifying
the First or Last of Multiple Words .
Initial Values
When an instance is executed the first time, initial values can be set for input
variables, internal variables, and output variables. For details, refer to
Initial
Value under the preceding descriptions of input variables, internal variables,
and output variables.
Retaining Data through Power Interruptions and Start of Operation
The values of internal variables can be retained through power interruptions
and the start of operation. When the Retain Option is selected, the variable
will be allocated to a region of memory that is retained when the power is
interrupted and PLC operation starts.
Algorithm
Enter the logic programming using the registered variables.
Operand Input
Restrictions Addresses cannot be directly input into instruction operands within function
blocks. Addresses that are directly input will be treated as variable names.
Note Exception: Input directly or indirectly specified addresses for Index Registers
IR0 to IR15 and Data Registers DR0 to DR15 directly into the instruction
operand. Do not input variables.
Input constants directly into instruction operands.
• Ladder programming language: Enter hexadecimal numerical values
after the # and decimal values after the &.
• Structured text (ST language): Enter hexadecimal numerical values af-
ter 16# and enter decimal numerical values as is.
Comment
A comment of up to 30,000 characters long can be entered.
2-2 Instance Specifications
2-2-1 Composition of an Instance
The following table lists the items that the user must set when registering an
instance.
Item Description
Instance name Name of the instance
Language
Variable definitions The programming and variables are the same as in
the function block definition.
Function block instance areas The ranges of addresses used by the variables
Comments A comment can be entered for each instance.