Thank you for the post. I have developed many LabVIEW VIs for Multisim (some that we haven't posted yet - so please stand by) and I have had this happen on occassion and it is likely due to one of several issues as outlined below.
A) I have forgotten to change the Instrument ID (in the block diagram - not on the front panel) to something unique in the VINAME_multisimInformation.vi (thus a conflict and therefore Multisim cannot load the instrument as something unique.
B) I have changed a label or deleted a control on the front panel that I am not supposed to - such as the Repeat Data control for a Source Instrument (LV input to Multisim) or Sampling Rate or Interpolation Method controls for a Measurement Instrument (Multisim output to LV). Although they don't connect to anything, these are necessary for the instrument to load.
C) Before targeting the build as a llb I save the target VI as a ".vi" and not a ".vit" as required.
If you would like, you can send the VIs and Project to myself or Nestor and we can take a look and try to build this for you and provide feedback to the group (as it may be a common problem that everyone can benefit from).
Business Development Manager
National Instruments - Electronics Workbench Group
50 Market St. 1-A
S. Portland, ME 04106
Tel. (207) 892-9130
Fax. (207) 892-9508
Officially, Multisim 9 supports LabVIEW based VIs created in version 8.0, however, it's not possible to run LabVIEW based instruments created in version 8.5.
In the meantime, a possible workaround is to create your VIs with LabVIEW 8.2.1. I already did some tests with input/output instruments (created in LabVIEW 8.2.1) and they worked in Multisim 9. Here is my suggestion:
C:\Program Files\Electronics Workbench\EWB9\lvinstruments
Your custom instrument must be placed in the same folder.
Please let us know how this works.
National Instruments, EWB Group.