Mitsubishi Electric MELSEC Q Series User Manual page 446

8 DEDICATED INSTRUCTION
[Operation at execution of WFWRITE instruction]
Error
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(1) When the WFWRITE instruction is completed, the completion device (bit device)
set in ((D) + 0) turns on in the END processing of the completed scan, and turns
off in the next END processing.
When an error occurs, the completion device set in ((D) + 1) turns on and an
error code is stored into the completion status (word device) set in ((S1) + 1).
Sequence program
WFWRITE instruction
Completion device
Completion device +1
(2) An error will occur if the CompactFlash card runs out of a free area during data
write to the file. The data already written to the file before error occurrence
remain in the CompactFlash card.
(3) When data are written in binary and the specified file position of data write is
beyond the existing file position, the write is completed normally with no data
written.
"0" is stored into the write result ((S1)+3).
When the dedicated instruction is abnormally completed, the abnormal completion
signal ((D) + 1) turns on and a corresponding error code is stored into the completion
status ((S1) + 1).
Check the error status according to the error code and take corrective action.
Refer to Section 9.3 for the error code.
END
Scan Scan
processing
Instruction execution
OFF
OFF
Write to file
MELSEC-Q
END END
Scan
processing processing
ON
ON
When abnormally completed
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