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Chapter 4. Ladder Diagram (LD) Programming
4.8.11
Move
When the MOVE function receives power flow, it copies data as individual
bits from one location in PLC memory to another. Because the data is
copied in bit format, the new location does not need to be the same data
type as the original.
The MOVE function copies data from input operand IN to output operand
Q as bits. If data is moved from one location in BOOL (discrete) memory
to another, for example, from %I memory to %T memory, the transition
information associated with the BOOL memory elements is updated to
indicate whether or not the MOVE operation caused any BOOL memory
elements to change state. Data at the input operand does not change
unless there is an overlap in the source and destination.
Note: If an array of BOOL-type data specified in the Q operand does not include all the bits in a
byte, the transition bits associated with that byte (which are not in the array) are cleared
when the Move function receives power flow. The input IN can be either a variable providing
a reference for the data to be moved or a constant. If a constant is specified, then the
constant value is placed in the location specified by the output reference. For example, if a
constant value of 4 is specified for IN, then 4 is placed in the memory location specified by Q.
If the length is greater than 1 and a constant is specified, then the constant is placed in the
memory location specified by Q and the locations following, up to the length specified. Do
not allow overlapping of IN and Q operands.
The result of the MOVE depends on the data type selected for the function, as shown below. For
example, if the constant value 9 is specified for IN and the length is 4, then 9 is placed in the bit
memory location specified by Q and the three locations following:
MOVE BOOL
Enable
MOVE
BOOL
4
IN
Q
9
Output
MSB
(Length = 4 bits)
The MOVE function passes power to the right whenever it receives power.
160
PACSystems* RX7i, RX3i and RSTi-EP CPU Programmer's Reference Manual
Enable
OK
LSB
1 2
3
4
MOVE WORD
OK
MOVE
WORD
4
9
IN
Q
Output
9
9
9
9
(Length = 4 words)
Mnemonics:
MOVE_BOOL
MOVE_DINT
MOVE_DWORD
MOVE_INT
MOVE_REAL
MOVE_UINT
MOVE_WORD
GFK-2950C
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