Simulink Reference

Detect Change

Detect a change in a signal's value

Library

Logic and Bit Operations

Description

The Detect Change block determines if an input does not equal its previous value where

• The output is true (not 0), when the input signal does not equal its previous value.
• The output is false (equal to 0), when the input signal equals its previous value.

Data Type Support

The Detect Change block accepts signals of any data type supported by Simulink, including fixed-point data types.

Parameters and Dialog Box

Initial condition

Set the initial condition for the previous input U/z.

Characteristics

Direct Feedthrough	Yes
Scalar Expansion	Yes

See Also

Detect Decrease, Detect Fall Negative, Detect Fall Nonpositive, Detect Increase, Detect Rise Nonnegative, Detect Rise Positive

Derivative

Detect Decrease

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