Mitsubishi Electric MELSEC-Q Series Programming Manual page 137

Even if a command for SP.SFCSCOMR instruction turns ON, SP.SFCSCOMR instruction is not executed.
• For the comment files to be used with S(P).SFCSCOMR, set them in the PLC File tab of the PLC parameter dialog box or
at "file set instruction (QCDSET(P)) for comments". Executing S(P). SFCSCOMR without setting the comment file to use, 0
is stored to "the total number of steps ((d1) +0)" and "the number of steps that have read comments ((d1) +1)" At this time,
the device specified in (d2) turns ON for 1 scan. When the comment file setting is configured in the PLC File tab of the PLC
parameter dialog box but the file does not exist at power-on or reset, "FILE SET ERROR" (error code: 2400) will occur.
• The following table lists the availability of reading comments stored in the memories by the S(P).SFCSCOMR instruction.
 Readable,  Not readable
Memory type
SRAM card (drive 1)
Flash card (drive 2)
Standard ROM (drive 4)
ATA card
SD memory card
*2 If the S(P).SFCSCOMR instruction is executed to the ATA card or SD memory card where the comments are stored, an operation error
(error code: 4130) occurs.
• While SFC program is not executed, reading comments is not performed even if executing S(P).SFCSCOMR instruction.
Executing S(P).SFCSCOMR instruction at a status without SFC program being executed, 0 is stored to "the total number of
steps ((d1) +0)" and "the number of steps that have read comments ((d1) +1)". At this time, the device specified in (d2)
turns ON for 1 scan.
• With S(P). SFCSCOMR instruction, comments for the normal SFC program can be read. Comments of a SFC program to
control program execution are not read. Executing S(P).SFCSCOMR instruction specifying a SFC program for program
execution control, 0 is stored to "the total number of transit conditions ((d1) +0)" and "the number of steps that have read
comments ((d1) +1)". At this time, the device specified in (d2) turns ON for 1 scan.
• S(P).SFCSCOMR instruction cannot be executed simultaneously with S(P).SFCSCOMR instruction or S(P).SFCTCOMR
instruction. Executing S(P).SFCSOMR, and if S(P).SFCSCOMR instruction or S(P).SFCTCOMR instruction is executed
before reading comments completed, the 2nd instruction will be de-activated.
• When the S(P).SFCSCOMR instruction is attempted to be executed while SM721 is on, the instruction will not be executed.
However, when the execution condition is met, the instruction will be executed in the next scan. SM721 turns on in the
following operations:
Function
The S(P).SFCSCOMR instruction or the S(P).SFCTCOMR instruction is executed.
The COMRD(P), S(P).FWRITE, S(P).FREAD, or SP.DEVST instruction is executed.
A file in the ATA card, SD memory card, or standard ROM is accessed by the read from PLC or write to PLC function, or by other file access operations.
*3 Effective only with the Universal model QCPU and LCPU.
• For the Universal model QCPU and LCPU, when the S(P).SFCSCOMR instruction is attempted to be executed while online
change (inactive block) is executed to the SFC block of comment read target, the instruction will not be executed. However,
when the execution condition is met, the S(P).SFCSCOMR instruction will be executed in the next scan.
Availability of reading comments



*2

*2

4 SFC PROGRAM CONFIGURATION
4.8 SFC Comment Readout Instruction
4
*3
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