Link type – Rockwell Automation 8520-9API 9/Series OCI API Developer's Guide User Manual

Page 57

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4–9

OCI Data Server Data Items

Publication 8520-6.6 - August 1999

Your OCI application program must choose the link type to be used
based on your specific data needs. When you create an OCI
application program, you must choose the link type that meets your
needs. If your OCI application program requests a:

Manual Link. Data that is identified as a manual link type must
be requested by your application program to get an update.
Changes to the data are not automatically updated on the OCI
station by the control. Your application must request that the
control update the OCI station. The application program receives
only one update of the data from the control when the request is
made.

OCI

Server

1

2

9/Series Manual Link

1

3

DDE Application

RSLinx

The DDE Application requests the current data value for an

item contained in the OCI Server.

The Server sends the current value of the item to the DDE

Application.

2

The Server reads the current value from the processor

containing the item data point through RSLinx.

3

2

9/Series

CNC

OCI

Server

1

2

9/PC only Manual Link

1

3

DDE Application

The DDE Application requests the current data value for an

item contained in the OCI Server.

The Server sends the current value of the item to the DDE

Application.

2

The Server reads the current value from the 9/PC

processor containing the item data point.

3

2

9/PC
CNC

2

Link Type

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