Class; Data Type - Mitsubishi Electric MELSEC iQ-F FX5 Programming Manual

4.2

Class

The label class indicates how each label can be used from which POU.
The selectable class varies depending on the POU.
Global label
Class
VAR_GLOBAL
VAR_GLOBAL_CONSTANT
VAR_GLOBAL_RETAIN
Local label
Class
VAR
VAR_CONSTANT
VAR_RETAIN
VAR_INPUT
VAR_OUTPUT
VAR_OUTPUT_RETAIN
VAR_IN_OUT
VAR_PUBLIC
VAR_PUBLIC_RETAIN
4.3

Data Type

Labels are classified into several data types according to the bit length, processing method, or value range.
The following two data types are provided.
• Elementary data type
• Generic data type (ANY)
Elementary data type
The following data types are available as the elementary data type.
Data type
Bit
Word [Unsigned]/Bit String [16-bit]
Double Word [Unsigned]/Bit String
[32-bit]
Word [Signed]
Double Word [Signed]
FLOAT [Single Precision]
Description
Common label that can be used in program blocks and function blocks
Common constant that can be used in program blocks and function blocks
Latch type label that can be used in program blocks and function blocks
Description
Label that can be used within the range of declared POUs
This label cannot be used in other POUs.
Constant that can be used within the range of declared POUs
This label cannot be used in other POUs.
Latch type label that can be used within the range of declared POUs This label
cannot be used in other POUs.
Label that inputs to a function or a function block.
This label receives a value, and cannot be changed in POUs.
Label that outputs a value from a function or a function block
Latch type label that outputs a value from a function or a function block
Local label which receives a value, outputs it from a POU, and can be changed
in POUs
Label that can be accessed from other POUs
Latch type label that can be accessed from other POUs
Description
BOOL Represents binary status, such as ON or
OFF
WORD Represents 16-bit
DWORD Represents 32-bit
INT Handles positive and negative integer
values
DINT Handles positive and negative double word
integer values
REAL Handles the portion after the decimal point
of the float (single precision)
Effective digits: 7 (after the decimal point:
6)
Applicable POU
Program Function
block block
 
 
 
Applicable POU
Program Function
block block
 
 
 
 
 
 
 
 
 
Value range
0 (FALSE), 1 (TRUE)
0 to 65535
0 to 4294967295
-32768 to +32767
-2147483648 to +2147483647
128 -126 -126 128
-2 to -2 , 0, 2 to 2
4 LABELS
4.2 Class
Function



4
Function









Bit
length
1-bit
16-bit
32-bit
16-bit
32-bit
32-bit
23