Conditional Subsystem Initial Output Values
To initialize the output values for a conditional subsystem, initialize Outport blocks within the subsystem by using one of these methods:
Inherit initial output values from input signals connected to the Outport blocks.
Specify initial output values using Outport block parameters.
If the conditional subsystem is driving a Merge block in the same model, you do not need to specify an initial condition for the subsystem Outport block.
Inherit Initial Output Values from Input Signals
Simulink® attempts to use input signals connected to conditional subsystem
Outport blocks to initialize output values. This behavior is seen after
setting the Outport block parameter Source of initial output
Input signal. The same behavior is seen
when Source of initial output value is set to
Dialog and Initial output is set to
Valid input signals for setting initial output values include:
Output ports from another conditionally executed subsystem.
Output ports from a Model block with a Trigger block with the Trigger type set to
IC (initial condition) blocks.
Simulink signal objects attached to the signal line connected to the Outport block. If the
InitialValueparameter is defined, Simulink uses this value.
C Function blocks.
If the input signal is from a block not listed here, the Outport block uses the default initial value of the output data type.
When a conditional subsystem Outport block inherits its initial output value, after the model has been updated or run, an badge is displayed next to the Outport block.
You can also determine whether a conditional subsystem Outport block
inherits its initial output value by using the
If you are using classic initialization mode, selecting
signal causes an error. To inherit the initial output value from an input
signal, set the Source of initial output value parameter to
Dialog, set Output when disabled to
held, and set Initial output to the
. The badge is not displayed in classic initialization mode.
See Classic Initialization Mode.
Specify Initial Output Values Using Dialog Parameters
Explicitly set the initial output values in cases where you want to:
Test the behavior of a model with various initial values.
Set initial values to steady state and reduce simulation time.
Eliminate having to trace input signals to determine the initial output values.
To specify initial output values:
Open the dialog box for an Outport block within a conditional subsystem.
From the Source of initial output value list, select
In the Initial output box, enter the initial value.