Labwindows/CVI TCP/IP Instrument Drivers...

[Srinivasa Rao]

Hi,

I am in the process of exploring possibility of writing Labwindows/CVI instrument
driver to support TCP/IP interface with SCPI. Our SCPI provides interface
for GPIB, Serial & TCP/IP. We wrote Instrument Driver to support GPIB & Serial
interface. Do anybody has idea of TCP/IP interface and whether Labwindows/CVI
supports it or not? Do u know of any downloadable TCP/IP instrument driver
which could act as an example.

Thanks in advance.

Thanks & Regards,
Srini

[Andy Toth]

Srini,

I have been using LabWindow/CVI with TCP/IP lately. NI does provide for a nice example found under C:\MeasurementStudio\cvi\samples\tcp I have been using the client based example. The only issue is that based on multiple read operations I can only get 11 samples/sec. (0.090 ms). I have been trying to change/manipulate the example to get te speed up. I am running SCPI code. I had used the VISA layer and at best I was arround 4 samples/sec or (0.280 ms). Our instrument can run faster 50 sample/sec. in VB, but I am not sure how NI wrote their interface. There should be way to decrease packet size and sleep time. If you need help please contact me at atoth@keithley.com If you find out how to increase the speed through TCP/IP and LabWindows/CVI let me know?
I am working on the code at this minute (04/16/03) and trying to get the CVI app comminucate faster for TCP/IP.

Andy Toth
Keithley Instruments
Ph(440)498-2948