Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 User Manual

744
Table Data Processing Instructions Section 3-17
Precautions The stack must be defined in advance with SSET(630).
Examples When CIO 000000 is ON in the following example, SNUM(638) counts the
number of words from the beginning of the data region at D00004 to the stack
pointer position - 1 (D00006) and outputs the result to D00300. (In this case,
the stack pointer indicates D00007.)
3-17-15STACK DATA READ: SREAD(639)
Purpose Reads the data from the specified data element in the stack. The offset value
indicates the location of the desired data element (how many data elements
before the current pointer position).
This instruction is supported by CS1-H, CJ1-H, CJ1M, and CS1D CPU Units
only.
Ladder Symbol
Variations
Applicable Program Areas
Operands TB through TB+3: Stack control words
The first four words of the stack contain the PLC memory address of the last
word in the stack and the stack pointer (the PLC memory address of the next
available word in the stack.)
SNUM
D00000
D00300
000000
D00000
D00001
D00002
D00003
D00004
D00005
D00006
D00007
D00008
D00009
D:D00300
0003Hex
PLC memory
address
Stack
pointer
Stack pointer
Last word
in stack
PLC memory address of
last word in the stack
Counts number of data
words. (3 in this example.)
SREAD(639)
TB
C
D
TB: First stack address
C: Offset value
D: Destination word
Variations Executed Each Cycle for ON Condition SREAD(639)
Executed Once for Upward Differentiation @SREAD(639)
Executed Once for Downward Differentiation Not supported.
Immediate Refreshing Specification Not supported.
Block program areas Step program areas Subroutines Interrupt tasks
OK OK OK OK

Omron SYSMAC CJ - REFERENCE MANUAL 08-2008 Specifications

General

Brand	Omron
Model	SYSMAC CJ - REFERENCE MANUAL 08-2008
Category	Controller
Language	English