Casella CEL Software for Nomad (Standard Operation) - Manual (Page 33)

5. DYNAMIC DATA EXCHANGE
Dynamic Data Exchange (DDE) allows one application to access data and / or
control another.
The application providing the data is called the server and the one
requesting the data is the client. Online Pro acts as a server.
Online Pro allows other applications to request information from it
about the real time data it is collecting from monitor system. This data can
then be used for calculations in a spreadsheet, included in a word processor
report, or even used to keep a web site updated.
For details of how to use your applications as DDE clients, please
refer to their individual documentation.
DDE data transactions are based on a three level hierarchy, the top
level being the application (or service) name, then the topic and item names.
The Online Pro application / service name is OnlinePro (no space). It
always has available the topic information, that provides general information
about the state of the application. In addition, it has one topic for each
monitor system defined in the system, with the topic name being the same
as the monitor system name.
The Information Topic can be used to obtain these names. It
provides basic information about the application with the following items:
Item name Description
Realtime Gives the string “Yes” if Online Pro is
currently in real time mode, or “No” if
not.
MonitorSystem Gives the number of monitor systems
defined in the application.
MonitorSystem# Gives the name of the numbered monitor
system (e.g. item MonitorSystem2 gives
the name of the second monitor system).
This name can then be used itself as a
topic name to request information about
individual monitor systems.
# is a number between 1 and the number
returned by the MonitorSystem item.
The Monitor System Topic gives the following information about the channels
on the monitor systems:
Item name Description,
Channels Gives the number of channels on the
monitor system,
Name# Gives the name of the channel,
Channel# Gives the latest data value of the monitor
system channel.
# is a number between 1 and the number
returned by the Channels item.
DDE
Page 33 of 68
ONLINE Pro Application Software for
Automatic Monitor Systems - Users Handbook