2.2 Adding an I/O Device Driver Tag

The tag browser should remain open from the last exercise. If you have closed it, open it again using the Tag Browser button in the Configuration Toolbox. The Tag Browser is currently displaying tags of the serial port tag type.

1.  Expand the Types drop-down list and scroll up until you see "Modicon Driver".

2.  Select Modicon Driver in the drop-down list.

Modicon Driver is now displayed in the Types field, and the tag list below it is empty, as no Modicon driver tags currently exist for this application.

3.  Click the New button.

Because the Modicon driver tag type is selected in the Types drop-down list, a new Modicon driver tag properties folder opens and displays the entry fields necessary to configure the Modicon driver tag.

 

Note that "System" is selected in the Area drop-down list by default. This is because it was the last known entry for the Area property. This VTS behavior is convenient in situations where you are configuring multiple tags with the same Area property, as it speeds data entry for your tags.

 

4.  Enter "Modbus1" in the Name field.

5.  Press the Enter key on your keyboard to set the name in the Name field.

6.  Enter "Virtual Modicon PLC" in the Description field.

7.  Press the Enter key to set the description in the Description field.

The properties of the ID tab are now complete and should appear as in Figure 20. The second tab for the Modicon driver tag properties folder is the Options tab. We do not require the properties of the Options tab at this time. Instead, we will skip to the properties of the Serial tab.

Figure 20

8.  Click the Serial tab. The properties of the Serial tab display as shown in Figure 21.

Figure 21

Note the properties of the Serial tab. These properties identify and establish a connection to the Modicon I/O device to be associated with this driver tag. Additionally, these properties identify the serial port tag that the Modicon driver tag should use to transmit data to the I/O device.

By default, our serial port tag has been automatically selected in the Port field, as VTS recognizes it as the only serial port tag for this application. The remaining properties are set to the VTS defaults, and do not require modification.

Note: If it should happen that the serial port tag created in the previous exercise is not selected in the Port field, click the tag button,  to its right. The Tag Browser opens, and the serial port tag is selected in the tag list. Click the Tag Browser's Select button to choose the serial port tag.

The remaining Options, Modbus Plus and Virtual I/O tabs are used when different cards and protocols are configured in actual Modicon I/O devices. For this tutorial, these tabs do not require modification. Our Modicon driver tag is complete.

 

9.  Click the OK button. The new Modbus1 Modicon driver tag is now displayed in the Tag Browser.