User manual

Computer Gateway User Manual A-1 5/96

CG POINT PREPARATION

Appendix A

This appendix summarizes the requirements for preparation of specialized CG data points that

regulate the execution of control programs and hold results of control calculations for exchange

with other LCN nodes.

A.1 CG POINT BUILDING OVERVIEW

As explained in Section 2, there are two types of data points that reside in the CG, the

Advanced Control Interface Data Point (ACIDP) and the Calculated Results Data Point

(CRDP). Both point types can be used to store calculated results that are to be exchanged

between the host processor and other LCN nodes. The ACIDP also contains the

parameters that control the scheduling and execution of an associated ACP in the host

processor.

Both point types are built at an Operator Station that is running in the Engineering

Personality; however, each point that includes data storage must reference a previously

prepared Custom Data Segment (CDS) that defines the special parameters to be added to

that point.

A.2 CUSTOM DATA SEGMENT CONSTRUCTION

NOTE

The following information on preparation of Custom Data Segments is intended only as an

introduction. Please consult the

Control Language/AM Reference Manual

for details of CL

program preparation and the

System Control Functions

manual for additional information on

Custom Data Segments.

Custom Data Segments allow you to define new (nonstandard) parameters and add them to

data points. Once you define new parameters and add them to data points, they can be

accessed in the same manner as standard parameters. Up-to-10 Custom Data Segments can

be associated with any ACIDP or CRDP.

Custom Data Segments are constructed as Control Language (CL) Packages, each

consisting of a single CDS. These CL "packages" are compiled, then stored on the History

Module or on Floppy Disk for use when the individual data points are built. The Data

Entity Builder (DEB) is used to add instances of a CDS to one or more data points.

Each CDS consists of a Heading plus one or more parameters.