Configure an ArchestrA group object

Although the ArchestrA namespace is flat, ArchestrA groups provide an artificial grouping hierarchy. Items are added in the same way at both the ArchestrA data source and group levels. In both cases, the same ArchestrA attribute is referenced, the exception being the ArchestrA Item ID Prefix that is provided at the group level.

Add a group object to your ArchestrA data source hierarchy

1. Right-click the new data source object, and select Add ArchestrAGroup Connection.

   • A new object is created in the hierarchy tree and is named New_ArchestrAGroup_000 by default (in "edit mode"). Rename it, if desired. You are allowed to add up to 100 new group objects.

     The New_ArchestrAGroup_000 Parameters configuration view (right pane) is displayed.

2. Configure the new group object according to the following option definitions:

   • Device Group Name: Name of the topic that DDE or SuiteLink clients of Gateway Communication Driver connect to in order to access items at the ArchestrA group. Default value is the concatenation of the names of the ArchestrA object and the group object. This cannot be edited.

   • ArchestrA Item ID Prefix: A string prefixed to item names added through this ArchestrA group. For instance, a prefix of "Blower_" is added to an item such as "001.Temp1" to create an item request of "Blower_001.Temp1". Default value is blank.

   • Read Only: Check this box for the Gateway Communication Driver to make all the items connected through the ArchestrA data source as ‘read-only’. This is in addition to other read-only conditions that ArchestrA imposes. Clearing the selection removes the read-only condition for the item imposed by the Gateway Communication Driver. By default, the Read-Only check-box is selected.

Name an ArchestrA Group

• Each ArchestrA group or topic must be uniquely named for the data source associated with it.

• The ArchestrA group name should not be identical (same in a case-insensitive manner) to an item prefix. This can cause a name clash and an unexpected behavior.

• The ArchestrA group name should not be identical to an item name, or the first part of the item name. This can cause an ambiguity in Gateway Communication Driver namespace. For example, do not name an ArchestrA group "Float" if a "Float.PV.Value" item exists in the Galaxy.

For more information, see Use item prefixes.