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MELSEC-Q
11 INSTRUCTIONS AND FUNCTIONS
• Specify the length of the data to be written from the starting position specified in <offset 2>
for <number of bytes> in byte units.
If an integer variable or integer array is specified in <storage area for data to be written>,
the number of bytes specified when writing n elements is as follows, since one element
(variable) contains 2 bytes:
<number of bytes> = n 2
If a character variable or character array variable is specified in <storage area for data to
be written>, the number of bytes specified when writing n characters is as follows, since
one en character contains 2 bytes:
<number of bytes> = n
• The allocation, size and type of each data item in buffer memory should be managed by
the user.
Data is not converted during reading or writing data from/to buffer memory, etc.
• If multiple programs read or write from/to the same area of buffer memory, etc. at one time,
use exclusive control to the area to one program at a time using the ZRESERVE and
ZRELEASE instructions.
Common memory can be read/written by multiple programs concurrently. An error does
not occur even if a program makes a write request to the area of common memory where
another program is reading/writing data.
