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on sysVar

Valid for: CANoe DE • CANoe:lite DE • CANoe4SW DE • CANoe4SW:lite DE The event procedure type on sysVar is provided to react to value changes of system variables in your CANoe DE product. In contrast to messages, system variables are not blocked by CAPL nodes in the Measurement Setup. Therefore, when there are two CAPL nodes in series, both react to the same system variable with the event procedure on sysVar. In the procedure on sysVar X{ ... } there is a reaction to the event change of system variable X. The system variable can be accessed by the key word this within the event procedure, e.g. to determine the value of the variable with the ‘@’ syntax or the function sysGetVariable.
The time stamp of the last system variable change (in nanoseconds since measurement start) can be retrieved with “this.time_ns”. X must be the fully qualified name of the system variable, i.e. the variable name preceded by all namespace names, separated by ”::”. The system variable must exist at compile time. Please note that the automatic make mechanism in your CANoe DE product currently does not trigger a compile whenever a system variable definition changes. The procedure on sysVar is called only when the value of the variable changes. It can also be written as on sysVar_change. If you want to be notified of value updates to the variable which don’t change the value, you should use on sysVar_update instead. You can also react in the same way to value changes of specific elements of a system variable of type struct or generic array. For this, add the element to the name of the variable. For additional clarity, you can also use on sysVarMember instead of on sysVar.

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Example

In the following example there is a reaction to a change on the I/O input DI_0 (first input port), and the new value of the I/O signal is assigned to the signal IOValue of a CAN message transmitted by the node Gateway. 
on sysvar IO::DI_0
{
    $Gateway::IOValue = @this;
}

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Note

Starting with CANoe DE version 7.1 SP4, you can also define handlers for several system variables. For this, use the syntax “on sysVar (sysVar1 | sysVar2 | ...)”, e.g. “on sysVar (IO::DI_0 | IO_DI1)”. The handler is called whenever one of the system variables changes (or is updated if you use on sysvar_update). The keyword this can only be used in such a handler if all variables have the same data type. CAPL programs which contain such handlers cannot be used with versions < 7.1 SP4. Since version 7.2, you can retrieve the name of the system variable as a string constant with this.name and its namespace with this.namespace.