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The SpecView DDE Server allows the retrieval and setting of Instrument parameters across the Windows DDE Interface.

 

NOTE: DDE is an option for SpecView. If the option has not been purchased DDE will not function.  To find out if it is available see the list under Help - Registration Info

You can upgrade  your copy of SpecView by phone. Contact your SpecView distributor for details.

 

DDE Application Name

DDE Topic Name

DDE Status Topic

SpecView DDE Restrictions

Getting data from SpecView via DDE (DDE Read)  and Example of getting data

Setting data into SpecView via DDE (DDE Poke)  and Examples of setting data

 

The SpecView DDE Interface is somewhat unorthodox in its implementation due to practical considerations. as follows:

Normally, a DDE server would 'register' a whole set of topics and items for which conversations can be transacted.  For SpecView, this would mean that each and every variable in the SpecView Variables List    would have to be registered, and furthermore, each one would have to be requested over the comms link to supply any DDE Client that happened along.  This is clearly unfeasible.

Consequently, the SpecView DDE Server registers no variables by default - nor does it request anything from the comms.  When a DDE request comes in from a DDE Client, if it is the name of a variable or parameter that SpecView understands, then that variable begins to be requested over comms.  In the meantime, SpecView must have answered back to the DDE Client to allow the client to continue processing. SpecView can only answer back that the request succeeded - even if the instrument is down or the comms link has failed - this is because it could be up to 3 or 4 seconds before the comms engine knows (due to re-tries etc.) that the variable is not online.