Slow data transfer from FieldMax with USB and ActiveX to LabVIEW

[S. Piepho]

I have written a LabVIEW VI which gets data from a Coherent FieldMax-TOP laser power meter via a USB interface with ActiveX. The VI works and I get the LastData on the meter. But the transfer rate is very slow (about 2 seconds per data point). How can I speed up the data transfer rate?

[Ankita A.]

Hi,

If there is a driver associated with your device, you can use LabVIEW to call the driver dll directly. This would speed up the data transfer because there is overhead associated with ActiveX. Another option might be to use VISA with your device so long as you know the device communication protocol(see the following link)
http://zone.ni.com/devzone/conceptd.nsf/webmain/6792BAB18242082786256DD7006B6416?opendocument

If you want to keep using ActiveX, then try closing all teh other applications on your pc and that might increase the transfer rate.

Regards,
Ankita A.

[ohmduke]

Hi, I can't help you to speed up the data transfer because I'm trying to use the FieldMax Top ActiveX, but it
doesn't show all methods and properties I need :
FieldMaxRunMode
FieldMaxAdded
FieldMaxRemoved
FieldMaxData
DataDeliveryEnable
LastData
I'm using LabView 7.0 Express and I can't open your FieldMax.vi, can you save this vi in previous version 7.0 so I
can try it and undertand if LabView 7.0 is incompatible?
Thanks

[ohmduke]

Hi,
I just have modified your FieldMax.vi and now the speed is equal to
refreshing rate of FieldMax (about 10 readings for second).
I didn't be able to reply before, because I'm using LabView7.0
and I had to find someone to convert your vi from 7.1 into 7.0.

[resrchengee]

Hi, did you write your own ActiveX controller? The people at coherent told me that the ActiveX controller they made is not compatible with labview drivers? If you did would you mind sharing it?

[ohmduke]

Hi,
I didn't write the ActiveX, I have used the Coherent one.

[resrchengee]

Oh, ok .. I could not find the activeX controller from coherent. I downloaded the .exe with all the labview drivers etc. but the activeX control was not listed in the activeX .net panel

[Devin_K]

resrchengee,

I installed the software from Coherent's site, and it looks like the ActiveX server DLL is located at:
C:\WINDOWS\system32\FieldMax2DLLServer.dll
There is also another DLL there: FieldMax2Lib.dll

I think the DLL should be registered during the installation, but if not, have a look at the following document:
How Do I Register or Unregister An ActiveX Control?

Unfortunately I don't have your hardware or know the details of how to use this in your application.  Look for an explanation of using ActiveX with it in the Coherent product manual.

[xNIx]

Hi,

I know this is an quit old issue but just just now I have following demand:

I am using Labview 6.0 and the fieldmax TO drivers are only available from LV 7.x

Questions:

- Is there a chance to use USB in Labviw 6.0?

- Could anyone convert the VI to a version which could be run in LV 6.0?

Thx in advance!

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ohmduke wrote:
Hi,
I just have modified your FieldMax.vi and now the speed is equal to
refreshing rate of FieldMax (about 10 readings for second).
I didn't be able to reply before, because I'm using LabView7.0
and I had to find someone to convert your vi from 7.1 into 7.0.

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