Omron SYSMAC C200HS Operation Manual page 175

Data Movement
Example
00001
Stack pointer
Stack area
LIFO Stack Operation
(C=8000 to 8999)
In the following example, the content of C (HR 00) is 9010, and COLL(81) is used
to copy the oldest entries from a10-word stack (IR 001 to IR 010) to LR 20.
DIST(80)
001
HR 00
LR 20
Before
execution
Stack pointer
IR 001
decremented
0 0 0 2
IR 002
1 2 3 4
IR 003
A B C D
IR 010
Output
LR 20
1 2 3 4
When the execution condition is OFF, COLL(81) is not executed. When the exe-
cution condition is ON, COLL(81) copies the data most recently recorded in the
stack to D. The stack pointer, SBs, is then decremented by 1.
Digits of C:
Data can be added to the stack until it is full. DIST(80)'s stack operation can be
used together with COLL(81)'s read stack operation. COLL(81) can be set to
read on a FIFO or LIFO basis. Refer to 5-16-6 SINGLE WORD DISTRIBUTE
(80) for details.
Note LIFO stands for Last-In-First-Out.
Address Instruction
00000 LD
00001 COLL(81)
After one
execution
Stack pointer
IR 001
decremented
0 0 0 1
IR 002
A B C D
IR 003
IR 010
Output
LR 20
A B C D
3 2 1 0
Specifies the stack length (000 to 999).
A value of 8 indicates LIFO stack operation.
Section 5-16
Operands
00001
001
HR 00
LR 20
After two
executions
IR 001
0 0 0 0
IR 002
IR 003
IR 010
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