couple basic questions

Hello again, I come here every 5yrs or so.

I have a functioning linuxcnc system based on 2.7.0.  I've made a number of changes to Axis over the years.  I have the config files, etc. as well as the AXIS code. This is running on a POS computer for reasons I can't remember but having something to do with inconsistent timing on a machine I built.  I think the application you run to test timing on the much faster machine reported a glitch in it of some type.  I've run the R45 mill on this slower machine limited to 60ipm.  On the faster machine, it was up to 130ipm or more, but the acceleration caused my house to shake and the glitch sort of worried me.  Also, the encoders I have on the servos are like 1000p/rev in quadrature and that of course impacted things.

Something is now failing intermittently on this slower machine and I need to make a change.  I have sitting by it an HP DL380-G7 dual socket with 2 x X5660 CPUs and a lot of memory.  I have a parallel port card for this machine.  I also still have the faster machine I built that had the timing glitch.

I use gecko drives, servos on X,Y, Z and stepper on A (rotary)

1) I've see people have run Linuxcnc on DL380s but they were like Gen5s and I didn't see an G7s but I didn't do an exhaustive search.
2) if I bring over my config files and older version of Axis, will they run as-is or do I have to rebuild the files and add my changes to Axis?
3) Given 2.7.0 ran OK for me, should I just get a copy of 2.7.0 and install that on the dl380?
4) either way, the download page was a little confusing.  I downloaded linuxcnc_2.9.1-amd64.hybrid but just noticed the word 'hybrid'.
5) I now see a later version on the top,  LinuxCNC_2.9.2-amd64.hybrid.iso . If I wanted to to the latest, is that the version? Again, the word hybrid.

Thanks


 

Just swap the hdd over and see how you go.

Don’t worry about the hybrid bit, it’ll work as long as the machine is 64 bit, 32 bit not supported.

They are some differences in config, most of the time Linuxcnc will pick it up and convert it, but you’ll want to read the docs to really understand. I’d start with the 2.8 ones.
Be aware that that using an RTAI kernel will mean searching the forums to get a good idea of what’s happening in that respect, as RT PREEMPT is the what the official ISO uses.
So yeah if you’ve been away for 5 years it’s going to be a bit of new experience.
But if you’re happy and able just to put the old hdd in the new machine is should be pretty painless. Or just clone it to another one if you wanna go that way.
That’s the good thing about Linux swapping hdds from machine to machine is pretty easy unless there’s something exotic going on, or there’s a difference in “bitness”.

Thanks, I forgot that linux can boot about anything. I'll probably clone the drive using clonezilla first and try it on the dl380. I think the current system is a 32bit though. So if I test it and it works, I'll set that drive aside and try to build a new version using my config files and my Axis version.

The current machine is slow, I can only get 60ipm out of it, max, mainly because the encoders on the servos are 1000cpr (250 in quadrature, I think they were). When I had the faster machine on this mill, I had it running at 130ipm and it accelerated in 1/4 turn of the drive. I have it on an R45 mill and the table and vise are easily over 100lbs and at that acceleration, it shook the house. But the faster machine had a glitch of some kind reported by the timing program, can't remember the name, so I had to back off to this POS that I can't wait to pitch.

Thanks for the reminder.

Jerry

I cloned the drive and the system came up sans parallel port. It was listed as a communications port in the bios for some reason.

So I put an alias in: /etc/modprobe.d/alsa-base.conf

And it looks like it loaded, I haven't tested it yet, it reports as a parallel port. When I had screwed up the address it gave me an error asking if there really was a parallel port there. I'll test that tomorrow.

thanks, this is much better than rebuilding

One thing I forgot, you could set the new drive as dual boot, dependent on available space, and maybe make a "slow transition". Have "old, reliable & stable" on one partition and "bleeding edge" the other. You'd still be able to use your old system whilst testing the new without anything more technical than a reboot. Another beauty of Linux.

Here's where I am:

1) DL380 has latency in the 100,000 to 120,000 range. I turned off everything (c-states, hyper, turbo, virtual, power, etc,) and searched my lab for a graphics card to put in it, no luck. Turning things off limited it to 120us whereas before that, it went up to around 200us. It needs a graphics card, but the slots are only 4x and pickings are slim. Other issue with the DL380 is that it takes like 3-4minutes to get to the boot screen, and it has an issue with the parallel card that I still haven't tested. See the comment on modprobe above.

2) I checked the old, slow machine and the latency is up around 65us. It has integrated graphics and that's probably the issue but it's worked fine for 10yrs until it started failing recently. It will hang on the splash, hang in general, the keys seem sticky on jog sometimes, so it has to go. I also think that microstepping around curves wasn't smooth but there are a number of factors that can cause that. I think the PS is weak in it but I would have to bodge-in an external supply and with metal flying around, its not a good idea. I had a piece get into a very small hole in the controller box once, shorted the gecko and had to be replaced. Smoke and all.

3) I have an old AMD64 machine, latency on that is under 8us no matter what I do. I had other plans for this POS that I might have to rethink. It has 16x graphics in it, SSD, etc.

So door number three it is but I have to test the parallel port as the same card that is in the DL380 would be used in this one and the old linux doesn't like it. But, "I had big plans for that machine! Acting lessons, singing lessons, I was going to make it a star!"

I appreciate the help Mr. Cornholio but now wondering if maybe a later version of linuxcnc has better latency? If not, then I guess I use the AMD64 box for CNC and then find another low-power box for data collection in the lab.

In #2 above, the POS is a Point of Sale Piece of S$$T. It was called a ShuttleX. That is the one hanging and needs to be replaced. I used it years after my faster 3.2Ghz machine smoked the motherboard under a memory stick. It's latency was never all that good, up around 65us.

In #3 above, that one is just an old Piece of S$$T PC that has to be 16 or 17yrs old, maybe 20. I found a faster AMD64 CPU and put it in a few years ago. It has 8G of memory. I was testing the AMD64 and with virtualization turned off, etc. I am now down to less than 5us of jitter. It found the parallel card and is ready to rock. I want to clone the IDE drive over to a SATA SSD. Then that will be the machine for the larger mill.

I had plans for this older AMD64 PC. I do a lot of testing that runs for days collecting data and I'm just trying to cut power consumption. I have several other older machines I can use just that its a hassle to back them up, etc. and get the adapters working that connect to the meters that collect the data.

Bottom line, until I scrape together something else, I'll use the AMD machine. I wish I could find a PCIE 4X video card to test that didn't cost much. I did some searching on Amazon and they seem to be around 80+USD.

Thanks

Jerry

wait, people keep mentioning the real time kernel, RTAI? I believe that is the one I am running. the kernel name ends in those letters. also, is there a 32bit version I might be running vs 64? and if so, would that help things?
I am running:

GNU GRUB version 1.99-27+deb7u3

Debian GNU/Linux, with Linux 3.4-9-rtai-686-pae

thanks

That's a 32 bit RTAI kernel.