Chapter 3 Configuration Of Functions; Configuration Of Functions - Mitsubishi Electric MELSEC-Q/L Programming Manual

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CONFIGURATION OF FUNCTIONS

3.1
Configuration of Functions
Instructions available in the CPU module can be divided into a function name and an argument.
The application of a function name and an argument are as follows:
• Function name  Indicates the function.
• Argument  Indicates the I/O data used in the function.
Arguments are classified into source data, destination data, executing condition, and execution result.
Source (s)
A source is data used in an operation.
The following source types are available depending on the device specified in a function:
Device
Constant
Bit device and word device
Contacts cannot be input directly to sources that use bit devices.
Destination (d)
Data after the operation are stored to a destination.
Set a device in which data are to be stored to a destination.
Coils cannot be directly connected to destinations that store bit devices.
Executing condition (EN)
An input variable EN inputs an executing condition of a function.
Execution result (ENO)
An output variable ENO outputs an execution result.
For details of the configuration of functions for labels and structures, refer to the following.
 MELSEC-Q/L/F Structured Programming Manual (Fundamentals)
3 CONFIGURATION OF FUNCTIONS
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3.1 Configuration of Functions
Description
Specifies a numeric value used in an operation. Constants are set during programming so that they cannot be
changed while the program is being executed. Perform index modification when using them as variable data.
Specifies the device in which the data used in the operation are stored. Data must be stored to the specified
device before executing the operation. By changing the data to be stored to the specified device while a
program is being executed, the data used in the function can be changed.