FixPt Logical Operator (Fixed-Point Blockset)

The FixPt Logical Operation block is a masked S-function that performs the specified logic on its inputs. An input value is TRUE (1) if it is nonzero and FALSE (0) if it is zero.

The logic connecting the inputs is selected with the Operator pull-down menu. The supported logical operations are given below.


Logical Operator	Description
AND	TRUE if all inputs are TRUE
OR	TRUE if at least one input is TRUE
NAND	TRUE if at least one input is FALSE
NOR	TRUE when no inputs are TRUE
XOR	TRUE if an odd number of inputs are TRUE
NOT	TRUE if the input is FALSE

The number of input ports is specified with the Number of input ports parameter. The output type is specified with the Logical output data type parameter. An output value is 1 if TRUE and 0 if FALSE.

Note:
The Logical output data type selected should represent zero exactly. Data types that satisfy this condition include signed and unsigned integers and any floating-point data type.

The size of the output depends on the number of inputs, their vector size, and the selected operator:

For two or more inputs, the block performs the operation between all of the inputs. If the inputs are vectors, the operation is performed between corresponding elements of the vectors to produce a vector output.
For a single vector input, the block applies the operation (except the NOT operator) to all elements of that vector. The NOT operator accepts only one input, which can be a scalar or vector. If the input is a vector, the output is a vector of the same size containing the logical complements of the elements of the input vector.

When configured as a multi-input XOR gate, this block performs an addition- modulo-two operation as mandated by the IEEE Standard for Logic Elements.

The block icon displays the logic to be performed on the inputs. For a description of how the block icon displays the output data type, refer to "Block Icon Display".

Parameters and Dialog Box

Operator: Logical operator used to connect the inputs.
Number of input ports: Number of inputs.
Logical output data type: Output data type. You should only use data types that represent zero exactly.

Characteristics


Input Port(s)	Any data type supported by the blockset
Output Port	Any data type supported by the blockset that can exactly represent zero
Direct Feedthrough	Yes
Sample Time	Inherited
Scalar Expansion	Of inputs
States	0
Vectorized	Yes

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