Tag Area Filtering
What is Tag Area Filtering?
Tag area filtering provides you with the means to prevent tags that have been configured with a specified area from loading on a given workstation when the application runs.
Why Should I Use Tag Area Filtering?
Tag area filtering can be used in systems were the demand for memory on a given PC (or PCs) is lessened. It is particularly useful on older PCs with limited memory, or on PCs where tag licensing is restricted.
How Does Tag Area Filtering Differ From Alarm Area Filtering and Realm Area Filtering?
Tag area filtering prevents tags configured with specific areas from loading on a given workstation. Alarm area filtering hides alarms that have been configured with specific areas on the Alarm page on a given workstation. Realm area filtering hides tags configured with specific areas from given users according to the group to which their security account belongs, and is not limited to any one workstation (i.e. the user may logon to any workstation and they will still only have access to the tags permissible under their group).
Note: Tag area filtering does not affect the data presented on the Alarm page (i.e. users will be able to view alarm data corresponding to the unloaded tags in the History and Configured lists, and the filtered areas will still be visible in the Area Filtering drop-down list.) If you wish to hide these areas from view on the Alarm page, you must employ alarm area filtering in addition to tag area filtering (see Alarm Area Filtering).
Where is Tag Area Filtering Configured?
Tag area filtering is best achieved using workstation.ini files. Workstation.ini files are simple text files that can contain the same sections, variables, and settings as those that can be found in your application's Config.ini file; however, because these workstation.ini files are named identically to the PC to which they apply (e.g. MyPC.ini or Workstation09.ini), their settings only affect a single PC (unlike Config.ini, whose settings affect all PCs running the application).
How do I Configure Tag Area Filtering?
The following elements are involved in tag area filtering:
• A workstation.ini file named for the PC to which it should apply (e.g. MyPC.ini),
• The AreaFilter variable,
• The AreaExclude variable, and
• The [AREAS] section and subsequent area declarations.
Workstation.ini File
For each PC to which you wish to apply tag area filtering you must create a workstation.ini file. To create a workstation.ini file:
1. Create a simple text file that is named for the PC to which its settings should apply, and which has the .INI extension (e.g. MyPC.ini).
2. Save this text file to the application directory on the applicable PC.
Note: A PC will only obey the workstation.ini file that carries its name; therefore, each PC running your application may have a copy of all workstation.ini files in their respective application directories without adversely affecting your application.
Once you have created your workstation.ini file, you must configure it appropriately for tag area filtering as indicated below.
AreaFilter Variable
The AreaFilter variable indicates to your application whether or not tag area filtering should be turned on. The AreaFilter variable should be entered into your workstation.ini file (e.g. MyPC.ini or Workstation8.ini) under the [SYSTEM] heading and should be set to 1 to turn tag area filtering on. To do so, enter the following text into your workstation.ini file(s):
[SYSTEM]
AreaFilter = 1
Once you have added the AreaFilter variable to your workstation.ini file(s), you may add the AreaExclude variable as instructed below.
AreaExclude Variable
The AreaExclude variable indicates to your system what should be done with any areas not explicitly referenced in your workstation.ini file.
• If AreaExclude is set to 0, then any area not explicitly specified in your workstation.ini file will be loaded at startup. This is the default setting for the AreaExclude variable.
• If AreaExclude is set to 1, then any area not explicitly specified in your workstation.ini file will not be loaded at startup.
Note: If using AreaExclude, be careful that system areas are included in the list of tag areas to load, otherwise you may find that ports, drivers, fonts, etc. will not be loaded, thereby preventing the application from running properly on the workstation.
The AreaExclude variable should be typed on the line directly below the AreaFilter variable under the [SYSTEM] section in your workstation.ini file. An example is displayed below.
[SYSTEM]
AreaFilter = 1
AreaExclude = 1
Once you have added the AreaFilter and AreaExclude variables to your workstation.ini file(s), you may begin to reference the tag areas that you wish to load on each workstation using the [AREAS] section.
[AREAS] Section
The [AREAS] section is the workstation.ini section heading under which you may specify which tag areas to include or exclude from loading at startup. The [AREAS] section heading should be typed after the [SYSTEM] section heading and its variables (as indicated in the example below). Following the [AREAS] section, you may enter one of the following:
• To load tags configured with a specific area when the application runs, type the area, followed by an equals sign, followed by a 1.
• To prevent tags configured with a specific area from loading when the application runs, type the area, followed by an equals sign, followed by a 0.
• Tags in areas not specifically listed are loaded or not depending on the AreaExclude setting.
Note: Wildcard characters are not permitted in tag area filtering.
[SYSTEM]
AreaFilter = 1
AreaExclude = 1
[AREAS]
Tanks = 1
Pumps = 0
Note: Once you have completed the configuration of your workstation.ini file(s), save the files and restart your application. (Workstation.ini files like Config.ini files are only read when the application initially runs.)
Some examples of different tag area filtering scenarios are provided in the sections that follow.
Tag Area Filtering Example 1