ions as each I/O device object is created (or cloned).
Furthermore, classes inherit from other classes. For example, a motor starter class 80 may be created as a subclass of the analog class 66. Objects that are instantiated from the motor starter class 80 have all of the attributes and operations of the motor starter class 80 as well as those from the analog class 66. Thus, a motor starter object has automatically (without need for additional user data entry) the current and voltage limit attributes as well as many other attributes of the motor starter class 80 and the analog class 66.
The object oriented model 50 of the present invention presents the same type of graphical user interface (GUI) 84 to the user irrespective of what device objects are being created and on what network. Thus, the same GUI 84 is used to create device objects for a motor starter device object as for a temperature sensor device object.
Referring now to FIG. 3, a flowchart 86 shows the operational steps for the present invention. In step 87, control starts. In step 88, the user configures a first I/O device in order to set the attributes of the first I/O device. In step 90, the user makes a copy of the second I/O device from the first I/O device. In the preferred embodiment, an object copy operation is performed by right mouse clicking on the first I/O device object in order to make a copy of the second I/O device object from the first I/O device object. In step 92, the attribute values of the second I/O device object are modified if desired. In step 94, if other I/O device objects need to created, control continues with step 88.
The user can perform steps 1-3 either at the site of the local master control computer 10 or at a computer that is remote from the industrial site (this is shown respectively in FIG. 1 as the local master control computer 10 or the optional remote master control computer 10′). Preferably, the configuration is performed off-line. In other words, the master computer 10 and/or 10′ is not connected to the network since a network connection typically slows down the configuration process. The remote site configuration of the I/O devices 12 has significant advantages since the configuration can be performed by control software engineers at their own location and then electronically sent to the industrial site. The user can also do the configuration of the first I/O device 12 and of the other I/O devices on-line at the industrial site.
In step 96 in FIG. 3, the user connects the master computer 10 or 10′ to the network in order to send the created device objects to the proper devices that are on the network. In this way, the software on the network I/O devices are updated with the newly created device objects. The newly created I/O device objects then operate in accordance with the attributes and operations of the newly created device objects. Control ends with step 98.
FIG. 4 shows a GUI wherein the user uses a dialog window to select a new I/O device object from which other I/O device objects are to be cloned. The user highlights (as shown by reference 100) the I/O device object that is desired to be cloned. In the preferred embodiment, the GUI presents at reference numeral 102 the I/O devices in a hierarchical fashion, such as but not limited to, having at the top of the hierarchy the manufacturer's name followed by different device types. The hierarchical arrangement allows the user to more quickly locate desired I/O device objects.
FIG. 5 is a computer screen showing that a motor starter object has been selected and displays the attributes and values of the object as shown by reference numeral 110. The input and output characteristics of the object are shown by reference numeral 112.
FIG. 6 is a computer screen that is used to configure the attributes (i.e., parameters) for a first device object. Once the user has completed the configuration, the user saves the configuration. To add another device object to the configuration that is identical to the first I/O device object, the user selects the first I/O device object and