Rockwell Automation 8520-9API 9/Series OCI API Developer's Guide - Manual (Page 13)

1–4 Open Control Interface (OCI) Overview
Publication 8520-6.6 - August 1999
To access a piece of data named num_axes on a specific CNC, you
enter this information into your application’s DDE Link function:
Service (or Application) Name Topic Name Item Name
ABOCISERVER CNC_1 NUM_AXES
Once you specify this information in your application program and
execute the request, the application establishes a link to the OCI data
server and requests the data or command.
Once installed and executing, the OCI data server is used to converse
between a 9/Series CNC (using RSLinx) or 9/PC CNC and your
application program (using DDE). Refer to your OCI Installation
Manual or 9/PC Installation and Integration Manual for details on
OCI installation and configuration.
The OCI data server provides a DDE interface for your application
program from a specific CNC. The service name for the OCI data
server is:
ABOCISERVER
The OCI data server runs in the Microsoft Windows NT
t
(4.0 or higher) operating environment.
OCI Data Server Read Data Requests
Your OCI application can request data from the CNC. Read requests
can be automatic or manual. Automatic items are added and
maintained on a watchlist at the control. Manual items are placed on
the watchlist just long enough to report the current value of the item.
Refer to page 4–1 for details on reading data items.
OCI Data Server Write Data Requests
Information can be written to your CNC using a Poke operation.
When a Poke request is made by your application program to the
OCI data server, the data server passes this data on to the CNC
processor which (if valid) will change the data item value.
The OCI Data Server