We had another good point today in the lab. One of the computers arrived earlier in the week and I installed linux in preparation for use. We got the proprietary software, SPEC by Certif, to control the diffractometer over the weekend. It’s the same software package I saw at Argonne and to a lesser extent in graduate school (though we didn’t need it for the SAXS-speckle experiments).

I am thankful for that experience as having to learn it at this point would require a major undertaking. Granted I’m still “learning” it, but I’m more or less able to function on my own. That goes double for having spent so much time learning linux in graduate school. Anyways, the software compiled and installed with not even a hiccup.

But we did much better. I managed to hook up a couple of motors to the controller/driver electronics, a couple of old MCU-2 racks from Advanced Control Systems. I can control the motors manually direct from the front panels, but the fun thing was to get those communicating with the linux box running SPEC. Now I can control the motors straight from the computer. From here I can control the number of steps/sec, the number of steps/degree, etc... and drive the motors to arbitrary positions.



A very large part of a diffractometer comes down to being able to control the motors with a high degree of precision and reproducibility, and all of it with a computer. So in essence, we’ve demonstrated this as a solved problem and it’s just a matter of repeating that solution in a few forms.

The MCU-2 units are sort of the “backup/extras”. For the primary 4-8 motors I’ve already purchased a nice set of modular step-pak controllers. That should give me a total of 12 controllable axes from the computer. That sure beats standing around inside a hutch turning a dial!