Boolean Variable

Specifies whether to evaluate the parameter by value or by reference. ByReference is appropriate for most use cases, where parameters map to channels in a system definition, because calling by reference allows changes to the value of the channel to propagate across all sequences that use the parameter.

• ByReference—When another real-time sequence calls this real-time sequence as a subsequence, the calling sequence operates directly on the mapped variable value. If the subsequence updates the parameter value, the mapped variable in the calling sequence also is updated. If the calling sequence updates the mapped variable value while the subsequence executes from another task, the parameter value in the subsequence updates as well. ByReference parameters can only be called by variables of the same data type as the parameter.
• ByValue—When another real-time sequence calls this real-time sequence as a subsequence, the parameter maps a copy of the variable value. If the calling sequence updates the mapped variable value while the subsequence executes, the parameter value in the subsequence is not affected. If the subsequence modifies the parameter value while the subsequence executes, the value of the mapped variable in the calling sequence is not affected. ByValue parameters can be called by variables of any logical data type.

Specifies the default channel in the system definition to assign to this parameter. The real-time sequence uses the Default Assignment unless you override the parameter value when you call the real-time sequence from a stimulus profile.

You can specify a channel by its alias or by the path to the channel in the system definition, for example: Targets/Controller/System Channels/Model Count

This property only appears if you use the variable as a parameter.

Specifies the default or initial value of the local variable. This property only appears if you use the variable as a local variable.