Mitsubishi Electric MELSEC-Q Series Programming Manual page 145

• While SFC program is not executed, reading comments is not performed even if executing S(P).SFCTCOMR instruction.
Executing S(P).SFCTCOMR at a status of SFC program not being activated, 0 is stored to "total number of transition
conditions ((d1) +0)" and "the number of transition condition that have read comments ((d1) +1)". At this time, the device
specified in (d2) turns ON for 1 scan.
• With S(P). SFCTCOMR 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). SFCTCOMR instruction specifying the SFC program to control
execution, 0 is stored to "the total number of transit conditions ((d1) + 0)" and "the number of transient conditions ((d1) +1)
". At this time, the device specified in (d2) turns ON for 1 scan.
• S(P).SFCTCOMR instruction cannot be executed simultaneously with S(P).SFCTCOMR instruction or S(P).SFCTCOMR
instruction. Executing S(P).SFCTOMR, 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).SFCTCOMR 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.
*4 Effective only with the Universal model QCPU and LCPU.
• For the Universal model QCPU, when the S(P).SFCTCOMR 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 instruction will be executed in the next scan.
Precautions
• Make sure to use comments to be read with S(P).SFCTCOMR after the device specified at (d2) turns ON. Comments to be
read before the device specified at (d2) turns ON become an indefinite value.
• If the number of transition conditions associated with active steps is larger than that of comments to be read in a single (n3),
the active step comments are divided into the number to be read in a single scan. Counting the total number of steps is also
performed with the same comment number (n3) for 1 scan. In case transition conditions are remained without being
counted when reading comments completed, the counting will be continued for the remained. Because of this, the number
of scans calculated in the following formula is required. (Comments to be actually stored are the same points stored in (d1)
+1)
*: It becomes a round-up below the decimal point.
• Execute "batch write of SFC program in RUN status", "online change (inactive block)", or "write of comment file in RUN
status" while the S(P).SFCTCOMR instruction is not executed. Also, execute the S(P).SFCTCOMR instruction while these
operations are not executed.
Operation Errors
Error code Description
2410 When a comment file specified at execution of S(P).SFCTCOMR instruction does not existed
4100 • When SFC block No. specified at n1 is other than 0 to 319
• When the number of readout comment specified at n2 is other than 0 to 256
• When the number of readout comments in a single scan specified at n3 is other than 0 to 256
4101 When exceeding the maximum value of the device in which stores comment data to be readout
4130 When the S(P).SFCTCOMR instruction is executed to the comment file in the ATA card or SD memory card
4 SFC PROGRAM CONFIGURATION
4.8 SFC Comment Readout Instruction
4
*4
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