I'm trying to help a colleague with LabVIEW experience interface a stepper motor into a piece of (biological) experiment apparatus. I know a little bit about steppers, and know they can be driven by a sequence of 5V Pulses (TTL) through four "inputs" (often called A, B, C, and D). A little bit of research found a number of Tutorials for LabVIEW control that involved running the Stepper through commands to an Arduino + "Stepper Driver Board" (to translate TTL inputs into "Current to Magnets") and a suitable 5V power supply to provide power for the motor.
Before watching the Video, my initial thought was to use a USB-DAQ device with some counter-timers (I had one lying around), but I was intrigued by the Arduino idea (and the much-lower cost!), though it would involve learning yet another Programming Language (well, I knew the mechanics of B+, but had never really done serious programming with it).
My current work setup is a PC running Windows 10 (64-bit), with LabVIEW 2019 SP1 (32-bit), LabVIEW Real-Time 2019, and the myRIO Software Toolkit (2019). Yes, I did think about using the myRIO, which I could easily program to give the set of TTL pulse trains to make the Stepper's Driver Board "do what I wanted", but that also seemed like "expensive overkill".
So I went to VIPM, downloaded LINX/MakerHub, and ran into a problem.
Well, that's (fortunately) not quite wat happened. I opened a VM that had a similar LabVIEW 2019/myRIO setup installed, and installed LINX on it. Seemed to install just fine. Ran through the Intro to MakerHub or LINX (I don't remember quite what it was), and then tried to load the first Demo routine. Got the message "Can't find Examples", and a suggestion that the Service "NI System Locator" was not running. "Nonsense", I thought, "I know it is running, because (a) I've been using Examples all the time, and (b) I often check the NI Services, particularly when I'm having problems installing/updating a LabVIEW system, and know its on my machine".
Nope, it was gone. But it was there (whew!) on "real" PC that was running the VM:. Unfortunately, I didn't clone the VM before the test, so I went through the process of removing NI Software and reinstalling LabVIEW 2019 + LVRT + myRIO Software Toolkit 2019 + other Bells & Whistles (OpenG). And, of course, NI System Locator reappeared.
So now I'll Clone First and test on Clone. But how do I install LINX on a "real" (i.e. not Community Edition) LabVIEW Professional system without getting NI System Locator "lost"?
I'll confess that when I did the Install, I did it "all at once", i.e. a single pass (except for the myRIO Software Toolkit), as opposed to the 2-4 pass system I usually use, i.e. LabVIEW, reboot, Toolkits and Modules, reboot, Drivers, with only necessary Additional Features added.
Anybody using Arduinos to drive Steppers "for real", i.e. not as a hobby? Has anyone seen something like this before?
I've had quite a few installation experiences, starting with LabVIEW 2011, where Services disappear and don't restart as part of the Installation procedure. Perhaps an alternate question which might be an even better solution (as NIPM Giveth, and NIPM seems to Taketh Away) would be "How can I restart an NI Service that "gets turned off" (or "not turned on") as part of an NIPM installation?"
Bob Schor
