Chapter 1 Overview - Mitsubishi Electric MELSEC iQ-F FX5 Programming Manual

1
OVERVIEW
1.1
Instruction Configuration
Many instructions available for CPU module are each divided into the instruction part and device part.
The instruction part and device part are used as follows.
• Instruction part: Indicates the function of the relevant instruction.
• Device part: Indicates the data used for the instruction.
The device part is further classified to source data, destination data, and numerical data.
Source (s)
Source is the data used in the operation.
Depending on the label or device specified in each instruction, the source becomes as follows.
Type
Constant
Bit device
Word device
Destination (d)
Data after operation is stored in the destination area.
However, some instructions require the data to be used in the operation to be stored before the operation.
Ex.
Binary 16-bit data addition instruction
+ s
(1): The data required for operation is stored before the operation.
(2): Only the operation result is stored.
A label or device to store data must be set for the destination.
Numerical values (n)
In an instruction which uses multiple devices or an instruction which specifies the number of repetitions, data to be processed,
and character strings, use numerical values to specify the number of devices, transfers, data, and character strings.
Ex.
Block transfer instruction
BMOV s
(1): The number of transfers executed by the BMOV instruction is specified.
A numerical value from 0 to 65535 or 0 to 4294967295 can be set for the size such as the number of devices, transfers, or
*1
characters.
Note, however, that when the size specification such as the number of devices, transfers, or characters is 0, the relevant
instruction results in non-processing.
*1 The setting range varies depending on the instruction. For details, refer to the description of each instruction.
1 OVERVIEW
24
1.1 Instruction Configuration
Description
The constant specifies a numerical value used in the operation.
It is set during program creation and cannot be changed during program execution.
The user specifies the device where the data to be used in the operation is stored.
Necessary data must be thus stored in the specified device before operation execution.
By changing the data to be stored in the specified device during program execution, the data to be used by the
instruction can be changed.
d +
(1)
d n
(1)
s1 s2 d
(2)