Introduction and installation question

Hi all. My son and I have been wanting to do our own CNC machine together. We started thinking we would like to do a scratch-build and have since shifted our thinking to saving-up for a Zen Toolworks 7x7 kit. Since a major illness I have not been able to work full-time for about 18 months so our funds are extremely limited and we are in the process of trying to procure a cheap (hopefully free) computer to run everything. We were delighted to see that there is such a fantastic piece of software... LinuxCNC ... available to us.

We have already been using Linux on an old Gateway PC that my father gave me for Arduino development and my son is using it for his college computer programming classes.

So my mother just gave me a Gateway laptop that is a Pentium 4 running at 2.2GHz. Installing the "lite" version of Mint crashed and burned after several attempts but the latest Lubuntu release installed like a dream and runs VERY well on it.

Now the question.... can I run LinuxCNC on Lubuntu? I tried to get the "Live" cd running and it won't even boot to a point where I get anything on the screen. I'm not afraid of having to compile and possibly rebuild the kernal if needed (been working with Unix of lots of flavors since the late 1980's) but all of my Google-fu skills have come up short in this department.

If I can't get this to work, I may have to abandon the LinuxCNC route and go with a PC interfacing with an Arduino to drive the machine unless I can score a better computer somehow... or convince my son that I need our other Linux box for the CNC

Hi

I tried to get the "Live" cd running and it won't even boot to a point where I get anything on the screen.

Which Live CD did you try?

The 10.04 based one may well not even boot, but the 8.04 Live CD will even install on a PII (albeit runs like c**p)

With a P4 that is the one you should be trying, but laptop is probably not the right one, unless you can turn a lot of power management etc off without melting it, it is unlikely to perform well

regards

I agree with the laptop suggestion. I just installed the latest distribution of LinuxCNC on a laptop. It runs, but I get "unexpected realtime delay" warnings.

thanks. I was afraid that might be the case. I was trying the 10.04 Live CD version.

I went out and scored an old P4 desktop for $25. It runs the 10.04 version with decent results on the latency test.. I'll most likely build around this PC.

I went out and scored an old P4 desktop for $25. It runs the 10.04 version with decent results on the latency test

Sounds the way to go.

I would still advise burning a 8.04 based Live CD, booting from it and choosing 'Try Linuxcnc' to test it without having to install
Once running from CD try the latency-test.

I have yet to test a single processor machine which did not run better on the Uni-Processor built 2.6.24-16-rtai kernel with the 8.04 build

regards

Thanks again for all the good advice everyone.

ArcEye wrote:

I have yet to test a single processor machine which did not run better on the Uni-Processor built 2.6.24-16-rtai kernel with the 8.04 build

Is that the default kernel that comes with the 8.04 Live CD? If so, I think I'll try that. I already have the Live CD burned.

Is that the default kernel that comes with the 8.04 Live CD?

Yes it is

Thanks for all the help everyone. I am going to go ahead and use this desktop. I put the 8.0.4 release on there andran the latency test with glxgears, ffirefox, gimp, some other stuff. Max jitter never went over 10990. So I think this system will work great!

FWIW it is a P4 2.8 GHz 512k cache 533MHz bus with 1GB RAM.

I'll keep the Lubuntu laptop for in-the-field Arduino development which it seems to do great with.

OK another related question... I have LinuxCNC installed from the 8.04 Live CD and I've been playing with it in some of the PC-speaker simulation modes so I know the install went just fine. It runs nice and smooth, but of course nothing is actually hooked-up just yet.

Now, I notice the software package is "EMC2 v2.3.0." Is it OK to upgrade to the latest-and-greatest version of LinuxCNC under 8.04 or will I break something?

(I know I am supposed to leave the Ubuntu version alone at 8.04 or I definitely WILL break something.)