Counting Step Number - Mitsubishi MELSEC-Q/L 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:
+
+ D0
(1)
(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
In cases where indirect designation is done by @
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.
(b) Devices with additional steps (the Basic Model QCPU, High Performance model QCPU, Process CPU, and
Redundant CPU)
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
(c) Devices with additional steps (Universal model QCPU(except Q00UJCPU) and LCPU)
1) Instructions applicable to subset processing
The following table shows steps depending on the devices.
Instruction Symbols
LD,LDI,AND,ANI,OR,ORI,
LDP,LDF,ANDP,ANDF,ORP,ORF
LDPI,LDFI
110
D0 D10
(1) (2)
Number of devices 2
D10 D20
Number of devices 3
(2) (3)
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 step over the number of
Added Steps
1
Devices with Additional Steps
Serial number access format file register,
Extended data register (D),
Extended link register (W)
Multiple CPU shared device*
Serial number access format file register,
Extended data register (D),
Extended link register (W)
Multiple CPU shared device*
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
Added Steps
(Number of
Instruction Steps)
1(2)
3
1(4)
3
Basic Number
of Steps
1
3