The FixPt Relay block is a masked S-function that allows the output to switch between two specified values. When the relay is on, it remains on until the input drops below the value of the Switch off point parameter. When the relay is off, it remains off until the input exceeds the value of the Switch on point parameter. The block accepts one input and generates one output. Specifying a Switch on point value greater than the Switch off point value models hysteresis, whereas specifying equal values models a switch with a threshold at that value. The Switch on point value must be greater than or equal to the Switch off point.

The Output scaling parameter supports these scaling modes when Output data type is a generalized fixed-point data type:

• Use Specified Scaling -- This is the default mode; it uses the scaling specified for the Output scaling parameter. 
• Best Precision: Vector-wise -- This mode produces the best precision based on the Output when on and Output when off parameters.

Parameters and Dialog Box

Switch on point

The on threshold for the relay.

Switch off point

The off threshold for the relay.

Output when on

The output when the relay is on.

Output when off

The output when the relay is off.

Output data type

Any data type supported by the Fixed-Point Blockset.

Output scaling

Radix point-only or slope/bias scaling. Additionally, the Output when on and Output when off parameters can be scaled using the constant vector scaling mode for maximizing precision. These scaling modes are only available for generalized fixed-point data types.

Override with doubles

If checked, the Output data type is overridden with doubles.

Conversions

Both the Switch on point and Switch off point parameters are converted to the input data type offline using round-to-nearest and saturation.

Characteristics

Input Port	Any data type supported by the blockset
Output Port	Any data type supported by the blockset
Direct Feedthrough	Yes
Sample Time	Inherited
Scalar Expansion	Yes
States	0
Vectorized	Yes