A DTM instance can offer command functions. These functions do not have a user interface, they can have arguments and optional default values.
Each command function shall be mapped to a method in the MethodSet of the device instance (see Figure 15). The arguments are mapped to the InputArguments and OutputArguments for the methods. Optional arguments shall be included.
Figure 15 – Example for source of function information
Table 65 – Method node information mapping
|
OPC |
FDT |
|||
|
Attribute |
Interface |
Method |
Data member |
Description |
|
BrowseName |
IFunctions |
FunctionInfo |
FunctionItem.Label |
|
|
DisplayName |
IFunctions |
FunctionInfo |
FunctionItem.Label |
|
|
Description |
IFunctions |
FunctionInfo |
FunctionItem.Descriptor |
|
The DTMInfoBuilder can offer information about static functions that are independent of a DTM instance. Such FDT Static Functions may be mapped to methods on the device type created for the DTM. The execution of the method on a device object will need to be mapped to the execution of a static function with a StaticFunctionProvider. The Frame/Server will need to hold the reference to the provider internally and use it for execution of the method (see Figure 16).
Figure 16 – Example for source of static function information
Table 66 – Method node information mapping for Static Function
|
OPC |
FDT |
|||
|
Attribute |
Interface |
Method |
Data member |
Description |
|
BrowseName |
IStaticFunctionInformation |
GetStaticFunctions |
StaticFunctionDescription.Label |
|
|
DisplayName |
IStaticFunctionInformation |
GetStaticFunctions |
StaticFunctionDescription.Label |
|
|
Description |
IStaticFunctionInformation |
GetStaticFunctions |
StaticFunctionDescription.Descriptor |
|