Introduction

The PI Interface for OPC HDA is an OPC HDA COM interface for bi-directional data transfer between an OPC HDA Server and a PI System. The interface accesses data from an OPC HDA Server. The design of the interface allows running multiple instances of the interface simultaneously. Each interface instance can connect to an OPC HDA Server, which may be on the same or a different machine. The interface may reside on a PI home node or a PI interface node.

Note: This interface has been built against a UniInt version (4.5.0.59 and later), which now writes all its messages to the local PI Message log.

See UniInt Interface Message Logging for UniInt 4.5.0.x and later Interfaces in the %PIHOME%\Interfaces\UniInt directory for details on how to access these messages.

[PIHOME] variable

The value of the [PIHOME] variable for the 32-bit interface depends on whether the interface is being installed on a 32-bit operating system (C:\Program Files\PIPC) or a 64-bit operating system (C:\Program Files (x86)\PIPC).

The value of [PIHOME64] variable for a 64-bit interface is located at C:\Program Files\PIPC on the 64-bit Operating system. In this documentation, [PIHOME] will be used to represent the value for either [PIHOME] or [PIHOME64].

The value of [PIHOME] is the directory which is the common location for PI client applications.

Note: We are revising product documentation and other literature to reflect the evolution of the PI Server from a single server to a multi-server architecture. Specifically, the original historian core of the PI Server is now referred to as the Data Archive.

Originally, the PI Server was a single server that contained the Data Archive and other subsystems. To add features and improve scalability, the PI Server has evolved from a single server to multiple servers.

While the Data Archive remains a core of the PI Server product, the product name "PI Server" now refers to much more than the Data Archive. Our documentation, including this user manual, is changing to use "PI Server" in this broader sense and Data Archive to refer to the historian core.