6.5. Domain Settings

The Domain Settings area of the Cascade Connect Setup window allows you to configure which datahub domain(s) Cascade Connect will retrieve its data from. You can work with multiple domains (Cascade DataHub) in a single Windows client program. The domain name gives each Cascade DataHub autonomy within the group. If a Cascade DataHub is run with no arguments then the domain name remains set to default.

Note

If you are using Cascade Connect without the Cascade DataHub you can leave the default value as shown, and disregard the rest of this part of the Setup window.

Figure 6-5. Domain Settings

Cascade Domains is a list of all the domain names currently in use. To add a new domain name, type the name into the entry field below the list, and then click the Add button. Domain names can be deleted by selecting a name in the list and clicking on the Delete button. The default for this field is the string: default. The configuration file syntax for this field is:

    domain   domainname
    domain   domainname
      .
      . 
      .

Multiple entries are written one per line.

Default Domain allows you to select a domain from those entered in the domain list, to use as the default domain. The default domain is the domain from which values are retrieved when they are referenced without a domain name. The default for this field is the string: default. The configuration file syntax is:

    default   domainname

Domain Separator is the character used in the Windows client program (i.e. InTouch, Excel, Word, etc.) to make a logical separation between the domain name and the point name. This option exists because not all Windows client programs allow for Cascade Connect's default separator, which is the colon (:) symbol. Each Windows DDE client has different rules for which characters are legal in defining tagnames, and this is why we have supplied a list of possible substitute values for the domain separator symbol.

The domain character you pick is only used to refer to data outside of your default domain. Variables or tagnames that are being gathered from a single datahub do not need the domain name or the separator character in the tagnames. The default entry for this field is a colon (:). The configuration file syntax is:

    colonsub   character

6.5.1. Examples using domain names

  1. Examples of data point names are:

        LIC02-432-PV
        
        AREA2:LIC02-442-PV

    The first data point above would be retrieved from the Cascade DataHub defined under the default option while the second data point would look for data in a domain called AREA2.

  2. Excel does not allow most punctuation characters in the names of its cells, so to pass a point with a domain separator you should use the period (.) character.

    Assume you are using Excel to read data from two Cascade DataHub (one in a domain you have called CONTROL and the other in a domain called LAB). Let's also assume you have defined the CONTROL datahub to be your default datahub domain (the domain you read most of your data from). Here is how you would define points for your Excel spreadsheet.

    • To retrieve data from the LAB datahub domain you would use the domain name, separator, and point name within your Excel spreadsheet, like this:

          LAB.LIC02_PV
    • To describe a data point from the default CONTROL datahub you would use the point name definition alone:

          LIC02_PV
  3. InTouch has a restriction that states that a tagname cannot contain the colon (:) symbol, so we use the @ symbol instead.

    Assume you are using InTouch to display data from three Cascade DataHubs: (AREA1, AREA2 and AREA3) and you have defined AREA1 as your default datahub domain. You may define the following points within your InTouch application.

    • To retrieve data from the AREA2 or AREA3 datahub domains you would use the following point name definition within your InTouch application:

          AREA2@LIC02_PV
          
          AREA3@FIC11_SP
    • To show a data point from the default AREA1 datahub you would use the following point name definition:

          AIC05_MV

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