Omron SYSMAC CS Series Instruction & Reference Manual page 501

 SREAD(639)
Reads the data from the specified data element in the stack. The offset value indicates the location of
the desired word (the number of words before the current pointer position).
Pointer to last
word in stack
-n
(n=3)
Pointer
Data in pointer position - n
(n=3 in this example.)
 SWRIT(640)
Writes the source data to the specified data element in the stack (overwriting the existing data). The
offset value indicates the location of the desired word (the number of words before the current pointer
position).
Pointer to last
word in stack
-n
(n=3)
Pointer
Data in pointer position - n
(n=3 in this example.)
CS/CJ/NSJ Series Instructions Reference Manual (W474)
Stack
Pointer
:
A
B
Data region
C
Pointer
(Unchanged)
Last word of
data in stack
Stack
Pointer
:
A
B
Data region
C
Pointer
(Unchanged)
Last word of
data in stack
Stack
:
A
B
Data region
C
A
Reads data from pointer
position - n.
(n=3 in this example.)
Stack
Overwrites data at pointer
position - n.
(n=3 in this example.)
:
M
B
Data region
C
3. Instructions
M
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