TECHNICAL BULLETIN
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[Issue No.] FA-A-0147-A
(2) Program
Item
Precaution
Replacement method
Reference
Number of steps
The number of basic steps differs in
some instructions.
If index modifications mentioned on
the left are frequently used in the
program, the program size may
exceed the storage capacity of the
replaced CPU module. After the
program controller type is changed,
check the program size using the
confirm memory size function. If the
program size exceeds the storage
capacity, take the following actions
or change the CPU module to that
with larger program memory.
Move parameters and device
comments to the standard ROM.
Reduce the reserved area for
online change.
Use the file register, extended data
register, and extended link register
within 64K words because the
number of steps decreases by one
when used in that way.
MELSEC-Q/L Programming
Manual (Common
Instruction)
The number of steps increases by
one when:
Index modification is performed.
A leading or trailing edge
instruction is used.
Bit devices are used as word data
by specifying digits using K1, K2,
K3, K5, K6, or K7, or by specifying
a device number of other than
multiples of 16.
(3) Parameter size
Item
Precaution
Replacement method
Reference
Parameter size
The parameter size increases
because the built-in Ethernet port
setting parameters are added.
*1
Delete unnecessary files and free
some space.
Move the parameter file to another
memory area.
-
*1: This applies when the QnUD(H)CPU is replaced with the High-speed Universal model QCPU.
