2 Instruction Descriptions
2-810
NJ-series Instructions Reference Manual (W502)
The following figure shows a programming example. A file position indicator is set at 100 bytes from the
beginning of the file.
• Execution of this instruction is continued until processing is completed even if the value of Execute
changes to FALSE or the execution time exceeds the task period. The value of Done changes to
TRUE when processing is completed. Use this to confirm normal completion of processing.
• Refer to Using this Section on page 2-2 for a timing chart for Execute, Done, Busy, and Error.
• You must use the FileOpen instruction to obtain the value for FileID before you execute this instruc-
tion.
• An error occurs in the following cases. Error will change to TRUE.
• The value of Origin is outside of the valid range.
• The SD Memory Card is not in a usable condition.
Related System-defined Variables
Name Meaning Data type Description
_Card1Ready SD Memory Card
Ready Flag
BOOL This flag indicates if the SD Memory Card is
physically inserted and is mounted normally, i.e.,
if it can be accessed by instructions and commu-
nications commands.
TRUE: Can be used.
FALSE: Cannot be used.
_Card1Protect SD Memory Card Write
Protected Flag
BOOL This flag indicates if the SD Memory Card is write
protected when it is inserted and ready to use.
TRUE: Write protected.
FALSE: Not write protected.
_Card1Err SD Memory Card Error
Flag
BOOL This flag indicates if an unspecified SD Memory
Card (e.g., an SDHC card) is mounted or if the
format is incorrect (i.e., not FAT16 or corrupted).
TRUE: Error.
FALSE: No error.
_Card1Access SD Memory Card
Access Flag
BOOL This flag indicates if the SD Memory Card is cur-
rently being accessed.
TRUE: Being accessed.
FALSE: Not being accessed.
_Card1PowerFail SD Memory Card
Power Interruption Flag
BOOL This flag indicates if an error occurred in complet-
ing processing when power was interrupted dur-
ing SD Memory Card access. This flag is not
cleared automatically.
TRUE: Error.
FALSE: No error.
Precautions for Correct Use
FileSeek_instance(A, abc, DINT#100,
_SEEK_SET, def,
ghi, jkl, mno);
LD
ST
abc
DINT#100
_SEEK_SET
A
FileSeek
Execute Done
FileID Busy
Offset Error
Origin ErrorID
FileSeek_instance
ghi
jkl
mno
def
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