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Minimum number
of inputs = 2
Maximum number
of inputs = 8
Operands for AND, OR, and XOR
Parameter
Solve Order
IN1
IN2 (Must be the same data
type as IN1.)
IN3 ... IN8 (Must be the same
data type as IN1.)
Q (Must be the same data type
as IN1 and IN2.)
Properties for AND, OR, and XOR
Property
Valid Range
Number of Inputs
2 to 8
GFK-2950C
Logical XOR
If the bits in the strings examined by XOR are different, a 1 is
placed in the corresponding position in the output bit string.
For each pair of bits examined, if only one bit is 1, XOR
places a 1 in the corresponding location in string Q.
If both bits are 0, XOR places a 0 in the corresponding
location in string Q.
Tips:
If string IN2 and output string Q begin at the same
▪
reference, a 1 placed in string IN1 will cause the
corresponding bit in string IN2 to alternate between 0
and 1, changing state with each scan as long as input is
received.
You can program longer cycles by pulsing the input to
▪
the function at twice the desired rate of flashing. The
input pulse should be one scan long (one-shot type coil
or self-resetting timer).
You can use XOR to quickly compare two bit strings, or
▪
to blink a group of bits at the rate of one ON state per
two scans.
XOR is useful for transparency masks.
▪
Description
Calculated by the FBD
editor.
The value to operate on.
The value to operate on.
Values to operate on.
The operation's result.
February 2018
Chapter 5. Function Block Diagram (FBD)
Allowed Types
Allowed Operands
NA
NA
BOOL, WORD
All
DWORD
BOOL, WORD
All
DWORD
BOOL, WORD
All
DWORD
BOOL, WORD
All except constants
DWORD
and variables located
in %S memory
Optional
No
No
No
Yes
No
241
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