User`s manual
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MELSEC-Q
2 STRUCTURE AND COMBINATIONS OF PROCESS CONTROL
INSTRUCTIONS
2.2.5 Process control instruction operation error
Operation errors from these process control instruction are stored in the following special
registers. For information regarding other than operation errors, refer to the error codes listed in
the QCPU(Q Mode)/QnACPU Programming Manual (Common Instructions). (The error codes are
stored in special register SD0.)
REMARK
The following contents for errors other than operation errors are stored in the special register.
Error code 4100.......... When there is data that cannot be handled.
4300.......... When the specified instruction is incorrect.
4301.......... When the process control instruction number of devices is incorrect.
4302.......... When a device that cannot be specified is specified.
(1) For error code 4100, the detailed information is stored in special registers SD1502 to
SD1503. At times other than when a process control instruction operation error occurs,
SD1502 and SD1503 are set to 0.
SD1502.......... This shows the error code when an error occurs in the process control
instruction.
SD1503.......... This shows the instruction process No. when an error occurs.
For an explanation of the error contents refer to the Chapter 14.
2.2.6 Instruction execution conditions
The process control instructions are instructions that are executed while the input condition is ON.
2.2.7 Number of steps
The number of process control instruction steps differs depending upon the number of instruction
characters, the device used, and whether or not an indirect setting is valid.
The basic number of steps for the extension instruction are as follows.
Number of steps in process control instruction
2
2
number of instruction characters (Note 1)
number of devices
Note 1: The number of characters is calculated by adding 1 when the number is odd. (For
example when rounding up the results of a division.)
R1000R200R100R0S.IN
1Step 1Step
1Step 1Step1Step
The "S." of the instruction code is not
included in the number of characters.
2+2/2+4=7Step
7Step
For details refer to QCPU (Q Mode)/QnACPU Programming Manual (Common Instructions).