Mitsubishi Electric MELSEC-Q Series - Instructions that May Need a Replacement after Conversion from Qnascpu to QCPU

7 REPLACEMENT OF PROGRAM
7 - 26
7.2.5 Instructions that may need a replacement after conversion from QnASCPU to
QCPU
Some instructions are not automatically converted upon the replacement of the QnASCPU with the
QCPU.
The following table shows the instructions that are not automatically converted and their measures.
Reviewing the program is recommended.
*1 For details, refer to the following.
FA-A-0068 Precautions for replacing A/QnA (large type) series CPU with Universal model QCPU
Substitute A/QnA (Large Type) series CPU with AnS/QnAS (Small Size) series CPU.
Instruction type
QnASCPU
instruction
Corrective action
Application
instruction
Index modification of entire
ladder
IX (Counter Measure)
Review the program and change manually.
*1
(Supplement)
Change candidate instruction:
[IX]
[ZPUSH]
Replace the IX instruction with the ZPUSH instruction and set the contents
of index modification table to index register.
[IXEND]
 [ZP.P]
IXEND
Modification value
specification in index
modification of entire ladder
IXDEV (Counter Measure)
Change the program so that the device offset values specified the IXSET
instruction are directly set to the index modification table using the MOV
instruction.
*1
IXSET
Print ASCII code instruction PR (Counter Measures)
Replace the instruction by using an alternative program.
*1
Print comment instruction PRC
Special format failure checks
instruction
CHKST
(Counter Measure)
Replace the instruction by using an alternative program.
*1
CHK
Format change instruction for
CHK instruction
CHKCIR
CHKEND
Program low-speed
execution registration
instruction
PLOW
(Counter Measure)
• Use the PSCAN instruction instead of this instruction when low-speed
execution type programs are replaced with scan execution type
programs.
• No instruction can be used if low-speed execution type programs are
replaced with fixed scan execution type programs.
Program execution status
check instruction
PCHK
(Counter Measure)
Check a program execution status on the Program monitor list screen of GX
Works2. For details, refer to the QCPU User's Manual
(Function Explanation, Program Fundamentals).
Application
instruction
Display instruction
LED (Counter Measure)
Setting an external display is recommended since the QCPU does not have
the LED display function.
LEDC
Status latch instruction
SLT
(Counter Measure)
There is no alternative action.
SLTR
Sampling trace instruction
STRA (Counter Measure)
Review the program and change manually.
(Supplement)
Change candidate instructions:
[STRA]  [TRACE] instruction
[STRAR]  [TRACER] instruction
STRAR
Program trace instruction
PTRA
(Counter Measure)
There is no alternative action.
PTRAR
PTRAEXE
Other instructions EROMWR
(Counter Measure)
Review the program and change manually. (Use the ATA card as a memory
card.)
(Supplement)
Change candidate instruction: [EROMWR]  [FWRITE] instruction
PID control instruction PID57
(Counter Measure)
There is no alternative action.
Special function modules instruction
Example: G. INPUT, G. PRN, etc.
G (P). [Instruction
name]
(Counter Measure)
Reprogram for the special function modules to use with the QCPU.