Add-On Instruction guidelines

Use the

aoi

keyword to declare an add-on instruction instance and definition.

Add-on instructions do not support inheritance.

Add-on instructions are allowed to have only specifically named routines. The routine names represent what the routine is for. Like the program, the AOI’s routine names define whether the routine is a logic, prescan, or enableInFalse routine. For example, to add an enableInFalse routine, add a routine called enableInFault.

To create an instance within a routine, you must add the instance and, at some point, provide the backing tag.

The backing tag is passed into the add-on instruction as the first parameter.
The data type comes from the add-on instruction definition and is updated when the definition changes.
The datatype name is the add-on instruction name with
_TYPE
appended to it. For example, for an add-on instruction named myAOI, the data type is named myAOI_TYPE.

You can specify routines in add-on instructions as Inline and external routines. To define an add-on instruction as a single file, you must specify the routines as inline.

You can mark the parameters of an add-on instruction as visible (true or false), which determines the default visibility of the parameter. Pins are visible by default.

Example qualifiers specific to add-on instructions	Description	Can be a qualifier
Visible	Default visibility of the parameter for the add-on instruction instances.	Yes
Required	Specifies that the parameter is required, and the pin is automatically visible. If visible is set to false, a warning should appear to the user.	Yes

      Aoi someAOI (input dint input1, output hidden dint output1) {
        tag dint localTag; 
      }