This blog post contains information relevant to the presentation Fab and I are giving at NIWeek 2019, titled Simplifying your HAL with LVOOP and DQMH®. The bit.ly/NIWeek2019-DQMH-HAL takes you back to this post. You can find the code we used for the demonstrations in a Bitbucket repository.
Have you ever wanted to create a Hardware Abstraction Layer for measurement instrumentation but were unsure where or how to start? With all of the documentation available (White Papers, Blogs, PowerPoint Presentations), you are introduced to terminologies such as OOP, Dynamic Dispatch, and Hardware Abstraction. For some, putting all this together can be a daunting task. Well, there is good news: this post provides an answer to this task. With a simplified process and tools readily at your disposal, you can create decoupled reusable Hardware Abstraction Layer (HAL) components. You can clone the repository or download it as a zip file. The Readme file on the repository includes instructions on how to set up the code on your computer, such as installing DQMH and some additional instrument drivers. The attached document contains the step by step instructions to create the code that you can download from the repository. For the latest version of this document, see the one in the repository. We will walk you through how to create a HAL using a DMM class. When we are done, you will know exactly how to create a reusable DQMH DMM HAL that provides an API that works well in both LabVIEW and TestStand. Ready? Let us dive in.
Version as of May 31st, 2019
[download id=”2478″]Initial version of the document:
[download id=”2461″]
On page 13 of the pdf, it says to add DMM.lvlibp as the top-level library. But I believe it is supposed to be the HAL Utility Library that was just created
Thanks for the catch. I have updated the document with the correct images.
Great post. Do you know where I can find part 2? Thanks.
Thank you HLT. I hope the post was helpful and you found it useful for future architectures. As for the part 2, I have not written part 2. The second part will discuss the Measurement Abstraction Layer (MAL) and the DQMH.
waiting for part 2, thanks for sharing! very informative and useful
Question to the overwrite of NameAndVersionNumber.
When I pull the packed library HAL Untility.LVLIBP like described in the PDF I’m getting Error 7 when attempting to overwrite it. If I replace the packed library with the unpacked on from the DEV directory it works like expected. What I’m missing here? Thanks, and looking forward to the part 2.
I’m not sure how you are getting the Error 7 when overriding a VI. Try rebuilding the HAL class again. Also, I noticed that you wrote “overwrite”. Do you mean override?
Great tutorial. Thank you for sharing your knowledge. Looking forward to Part II.
Q#1: DMM can be controlled through GPIB, USB, LAN or Serial port, etc. It seems DMM_Level0 class is designed for serial communication only? How to incorporate this change?
Q#2: Serial communication can be modeled as a separate class and DMM “use a” DMM. How will you make the change?
excellent post !
looking forward for next part !
Great article, thank you.
Just a little mistake, page 10, you asked “right click the protected folder”, but it is the class we should use
Hello,
great article, thank you!
It translates not only to labview but to many other tools as well :).
Any news on part 2? 🙂