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5.3 Variables ToC Previous Next

For all Variables specified in NamespaceIndex 0, the Attributes named in Table 5 shall be set as specified in Table 5.

Table 5 – Common Variable Attributes

Attribute Value
MinimumSamplingInterval Optionally, a server-specific minimum sampling interval is provided.
AccessLevel The access level for Variables used for type definitions is server-specific, for all other Variables defined in this standard, the access level shall allow reading; other settings are server-specific.
UserAccessLevel The value for the UserAccessLevel Attribute is server-specific. It is assumed that all Variables can be accessed by at least one user.
Value For Variables used as InstanceDeclarations, the value is server-specific; otherwise it shall represent the value described in the text.
ArrayDimensions    If the ValueRank does not identify an array of a specific dimension (i.e. ValueRank <= 0) the ArrayDimensions can either be set to null or the Attribute is missing. This behaviour is server-specific.If the ValueRank specifies an array of a specific dimension (i.e. ValueRank > 0) then the ArrayDimensions Attribute shall be specified.
Historizing The value for the Historizing Attribute is server-specific.
AccessLevelEx If the AccessLevelEx Attribute is provided, it shall have the bits 8, 9, and 10 set to 0, meaning that read and write operations on an individual Variable are atomic, and arrays can be partly written.

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