604
Table Data Processing Instructions Section 3-16
Operand Specifications
Description SREAD(639) reads the data from the address specified by the stack pointer
(TB+3 and TB+2) minus the offset value in C. SREAD(639) does not change
the data in the stack or the stack pointer.
SREAD(639) can be used to read the data for an item currently on a conveyor.
The position of the desired item is simply the number of items back (the offset
value) from the most recent item added to the conveyor.
Area TB C D
CIO Area CIO 0 to CIO 6143
Work Area W0 to W511
Holding Bit Area H0 to H511
Auxiliary Bit Area A448 to A959 A0 to A959 A448 to A959
Timer Area T0000 to T4095
Counter Area C0000 to C4095
DM Area D0 to D32767
Indirect DM addresses
in binary
@ D0 to @ D32767
Indirect DM addresses
in BCD
*D0 to *D32767
Constants #0001 to #FFFB
Data Registers --- DR0 to DR15
Index Registers ---
Indirect addressing
using Index Registers
,IR0 to ,IR15
–2048 to +2047 ,IR0 to –2048 to +2047 ,IR15
DR0 to DR15, IR0 to IR15
,IR0+(++) to ,IR15+(++)
,–(– –)IR0 to,
–(– –)IR15
A
A
B
C
TB
TB+1
TB+2
TB+3
TB+4
D
m
n
C
n
m
Stack
PLC memory
address
Pointer
Offset value
Last word
in stack
The data (A) is
not changed.
Reads the data (A) without
changing the stack pointer.
Reads the data (A) in the specified
word and outputs that data to D.
The address of the desired word is
calculated by subtracting the offset
value from the stack pointer address.
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