Counting Step Number - Mitsubishi MELSEC Q Series Programming Manual

3.8

Counting Step Number

The number of steps in CPU module sequence instructions, basic instructions, and application
instructions differs depending on whether indirect setting of the device used is possible or not.
(1) Counting the number of basic steps
The basic number of steps for basic instructions and application instructions is calculated by
adding the device number and 1.
For example, the "+ instruction" would be calculated as follows:
(2) Conditions for increasing the number of steps
The number of steps is increased over the number of basic steps in cases where a device is
used that is designated indirectly or for which the number of steps is increased.
(a) When device is designated indirectly
(b) Devices with additional steps (the Basic Model QCPU, High Performance model QCPU,
Devices with Additional Steps
Intelligent function module device
Multiple CPU shared device
Link direct device
Index register
Serial number access format file register
32-bit constant
Real constant
Character string constant
3-34
+
D0
(1)
+
D0 D10
(1) (2)
In cases where indirect designation is done by @
step over the number of basic steps.
For example, when a 3-step MOV instruction is designated indirectly (example: MOV
K4X0 @D0), one step is added and the instruction becomes 4 steps.
Process CPU, and Redundant CPU)
D10
(2)
Number of devices 2
D20
Number of devices 3
(3)
Added Steps
1
For even numbers: (number of characters) / 2
For odd numbers:
(number of characters + 1) / 2
Number of basic steps: 3
Number of basic steps: 4
, the number of steps is increased 1
Example
MOV U4\G10 D0
MOV U3E1\G0 D0
MOV J3\B20 D0
MOV Z0 D0
MOV ZR123 D0
DMOV K123 D0
EMOV E0.1 D0
$MOV "123" D0