Using Simulink

Triggered Subsystems

Triggered subsystems are subsystems that execute each time a trigger event occurs.

A triggered subsystem has a single control input, called the trigger input, which determines whether the subsystem executes. You can choose from three types of trigger events to force a triggered subsystem to begin execution:

• rising triggers execution of the subsystem when the control signal rises from a negative or zero value to a positive value (or zero if the initial value is negative).
• falling triggers execution of the subsystem when the control signal falls from a positive or a zero value to a negative value (or zero if the initial value is positive).
• either triggers execution of the subsystem when the signal is either rising or falling.

For example, this figure shows when rising (R) and falling (F) triggers occur for the given control signal.

A simple example of a trigger subsystem is illustrated below.

In this example, the subsystem is triggered on the rising edge of the square wave trigger control signal.

Blocks an Enabled Subsystem Can Contain

Creating a Triggered Subsystem