Dynamic Data Exchange (DDE)
Dynamic Data Exchange (DDE) allows other applications to "talk" to
SpectraPLUS-SC -applications can send commands to the analyzer and
request data in return. This powerful feature allows you to build
custom signal processing solutions using SpectraPLUS-SC.
DDE is supported by all major spreadsheet programs, databases and
programming languages. We recommend using Visual Basic for
Applications (VBA) which Microsoft has incorporated into the latest
versions of all their major applications. This provides a very
flexible yet easy to learn macro language which is consistent across
their entire product line. Note - DDE has support has been removed from
Visual Basic (v5.0 and up); however Excel still supports DDE through
VBA (Visual Basic for Applications).
DDE support consists of two major types of operations - Commands and Data Requests.
Commands are actions messages such as "Run" and "Stop" which are sent to SpectraPLUS-SC for control purposes.
Data Requests are messages such as "THD" or "Spectrum" which cause
SpectraPLUS-SC to send the corresponding data values to the requesting
Establishing a DDE Hot Link automatically:
It is possible to set up what is known as a "hot link" wherein
SpectraPLUS-SC will send an "advise" message whenever it has computed
new data values. When the application receives this advise
message it should then request the corresponding data. A
hot link can be quickly established using the external application's
<Paste Special> or <Paste><Link> menu command.
For example, to establish a hot link with Excel, perform the following
Highlight the Spectrum View in SpectraPLUS-SC.
Click on the <Edit><Copy> menu command in SpectraPLUS-SC
Go to Excel, highlight a destination cell and click on the <Edit><Paste Special> menu command.
Click "Paste Link" as the source type and press Ok.
At this point a "DDE hot link" will be established. Whenever the
spectral data changes, the spreadsheet contents will update
immediately. Any cells computed from these spectral values will
Estabishing a DDE link manually:
Before an application can "talk" to SpectraPLUS-SC it must first
initiate what is known as a "DDE conversation". When initiating a
conversation, the program must know the name of the DDE server and the
topic. When requesting data, the name of the item must be
known. All available Item names for SpectraPLUS-SC are documented
DDE Server name:
Topic names Supported: