RSView Supervisory Edition Installation Guide

8 • WORKING WITH TAGS• • • • •Minimum and maximumHMI tags allow you to set the minimum and maximum values that can be written to thenetwork device or data server. These values do not affect what is read from the device orserver.For example, if you specify a minimum of 0 and a maximum of 100, RSView would beable to read a value of 200 from a device and store it in memory, but would not be able towrite this value to the device.8 • PlaceholderStoring values in RSView’s memoryA memory tag can be used to store values without the need for an attached or accessibledevice. For example, you can use memory tags:• to store the result of a calculation.• temporarily, for example, to act as a counter or index.• to maintain information about the system’s current state, for example, which graphicdisplay was last displayed.For information about creating memory HMI tags, see Help.Setting up HMI tagsThese are the tasks involved in setting up HMI tags in an application:1. Create an HMI server if the application doesn’t already have one. Each HMI servercontains one tag database.2. In the tag database, create memory tags, or for device tags, map each tag name to adata server or DDE address.3. In graphic displays, alarm summaries, or anywhere else you plan to access a tag’svalue, map an object to a tag. At run time, the tag’s value is passed to the object.Browsing for tagsTo use a tag, you can type its name and path, or browse for it using the Tag Browser. Howyou open the Tag Browser depends on where you are in RSView.Opening the Tag BrowserTo open the Tag Browser, use one of these methods:• In the Command Wizard, for commands that take tags as parameters, click the browsebutton beside the Tag box.8-5