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Data can be sent down to the Instrument using the DDEPoke command.

Read the DDEPoke Examples

Due to the fact that (A) there can be a significant time delay before the data is sent, and (B) the data may not be accepted by the instrument (over-range etc.), the SpecView DDE Server reports back immediately that the DDEPoke succeeded.  It is the responsibility of the Client to only make one Poke request at any time.

The Status of the write process is reflected in the SpecView DDE Status Information.  These DDE items can have one of the following values:

•        Idle

•        Writing

•        Written

•        Write Error X

When a Client makes a DDE Poke request, it should monitor the PokeStatus item.  This will be changed as the state changes.  The Client will only know that the Poke request actually gave data to the instrument if the PokeStatus shows 'Written'.  If 'Write Error X' is shown, then the write failed for the reason given.

'Idle' is shown before the very first Poke request is actioned, and never afterwards (because 'Written' or 'Write Error' is shown after any Poke.

Data is sent to SpecView using the CF_TEXT format, and SpecView formats it to the correct type depending on the variable prior to sending.  This may or may not require more or less decimal places for numbers that is supplied. SpecView will add or truncate  as necessary, so it is always best to send the full resolution (all decimal places) to be written.

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