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Instruction Execution Times and Number of Steps Section 10-5
For example, if !MOV is used (MOVE instruction with immediate refreshing),
the program capacity of a CV-series PLC would be 4 words per instruction
and that of the CJ-series PLC would be 7 (4 + 3) steps.
Number of Function Block Program Steps (CPU Units with Unit Version 3.0 or Later)
Use the following equation to calculate the number of program steps when
function block definitions have been created and the instances copied into the
user program using CS/CJ-series CPU Units with unit version 3.0 or later.
Note The number of instruction steps in the function block definition (p) will not be
diminished in subsequence instances when the same function block definition
is copied to multiple locations (i.e., for multiple instances). Therefore, in the
above equation, the number of instances is not multiplied by the number of
instruction steps in the function block definition (p).
Example:
Input variables with a 1-word data type (INT): 5
Output variables with a 1-word data type (INT): 5
Function block definition section: 100 steps
Number of steps for 1 instance = 57 + (5 + 5)
× 6 steps + 100 steps + 27 steps
= 244 steps
Number of steps
= Number of instances × (Call part size m + I/O parameter transfer part size n × Num-
ber of parameters) + Number of instruction steps in the function block definition p
(See note.)
Contents CS/CJ-series CPU Units
with unit version 3.0 or later
m Call part 57 steps
n I/O parameter
transfer part
The data type is
shown in parenthe-
ses.
1-bit I/O variable (BOOL) 6 steps
1-word I/O variable (INT,
UINT, WORD)
6 steps
2-word I/O variable (DINT,
UDINT, DWORD, REAL)
6 steps
4-word I/O variable (LINT,
ULINT, LWORD, LREAL)
12 steps
p Number of instruc-
tion steps in func-
tion block definition
The total number of instruction steps (same as standard
user program) + 27 steps.
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