Instrument emulation for testing purposes

[ilyak]

Hi All:

This is a more general question about software system design:

I have a program, written in C++, that talks to several NI instruments on different buses - there is GPIB, Ethernet, DAQmx, serial. The program performs some testing functionality, controls the instruments, stores the results, etc. Fairly standard stuff.

However, we keep making changes to the aforementioned program and, before it can be released to into the wild, it itself has to be tested. What I wanted to do is to script this testing and test some of the components of the program that don't involve talking to the instruments. This can be done off-line on the build server automatically, for example. But in order to do that I will have to turn off, sort of speak, the instruments beforehand.

Does anyone have experience designing support for this sort of instrument emulated mode? What are general design strategies to do that? What caveats should be avoided? Perhaps there are tools/libraries available that do that.

Thank you,

-Ilya.

[Adam G]

Hello Ilya,

I do not have any experience doing what you are asking. I was wondering if you are running into any problems when implementing this? Does anyone else out there have experience with this?

Best Regards,

Adam G 

[ilyak]

Hi Adam:

I'm not running into any problems with this feature.

At this point I'm just collecting data and creating initial design.

I asked this question to see, first of all, if this kind of software already available and I don't have to write it from scratch. If this isn't the case I wanted to know if someone else had to do this kind of software before and if they can share the experience.

-Ilya.

[D_Biel]

Illya,

National Instruments does not offer a test environment for C++. However, If you would like to test your application using a 3rd party testing environment and would like to simulate your devices, this is available for DAQmx, GPIB and Serial. Through MAX, you can simulate DAQ devices that will allow your code to run without any hardware hooked up. For GPIB and Serial, National Instruments sells an Instrument Simulator (http://sine.ni.com/nips/cds/view/p/lang/en/nid/10763). The Instrument simulator might be a bit expensive for simple testing though.

[Dennis_Knutson · Accepted solution]

For a software only option, you would use only IVI drivers for the serial/GPIB/Ethernet instruments. The IVI spec requires a simulation mode.

D Biel - that link does not work. Is that another AE only page that we see posted from time to time?

[D_Biel]

Thanks for the advice Dennis.

No the link is not an AE page, the ")." got caught in the hyperlink. Here is a better one:

http://sine.ni.com/nips/cds/view/p/lang/en/nid/10763