LinuxCNC still used

[vtpup]

I'm still using LinuxCNC over a decade later after the development so kindly provided in the old forum by Saintless for my old Thinkpad 600E laptop, and a CNC mill. https://oldforum.puppylinux.com/viewtopic.php?t=95640

Unfortunately as of today, both my two TP 600Es have died, and cannot be repaired. I have one other laptop with a parallel port left (required by LinuxCNC). I cannot use a desktop pc for lack of space and poor environment (unheated shop in winter time Vermont). A laptop can be carried into the shop when needed for a cut on the mill, but is kept in a heated space normally.

Anyway, my remaining parallel-ported laptop is a Thinkpad T43 (32 bit). It will boot and run the old live CD LinuxCNC ISO that Saintless made for the TP600Es called Ubuntu8.4-test-2.iso and is still available online for download. https://www.dropbox.com/sh/ca58blnh2m6h ... Th0oa?dl=0

However, there is a problem running it on the Thinkpad T43, and that is latency. The TP600E's were great under LinuxCNC with very low latency, but the T43 has a regular 64 second periodic latency spike, called the "SMI issue". It can be worked around according to http://wiki.linuxcnc.org/cgi-bin/wiki.p ... gSMIIssues. That involves adding a kernal patch module.

I thought I would give that solution a try, but to do so I wanted to first create a partition on the hard drive for a full installation of the Saintless' LinuxCNC version above. This would also make it easy to add the configuration file for my CNC Mill.

Unfortunately when I followed the instructions Saintless gave for installing here: https://oldforum.puppylinux.com/viewtop ... 34#p799834 the installation starts to boot almost to completion, but then fails

On starting I get what look like normal messages scrolling by some of which seem to be complaining about /var/log being a read-only filesystem. Eventually the program aborts saying it can't transfer a file to /var/log/old.

So, I guess maybe my options are to try to just run off of the live ISO, but somehow modify it to include the kernel module fix, and my CNC Mill's configuration files. The ISO can probably be started off of a thumb drive, instead of CD, to make it a little quicker to load.

Anyway, those are my present thoughts. But also just wanted to thank Saintless again, and say I still run this old program, on an old mill, from old computers, over a decade later!

[Wiz57]

Have you thought about a USB to Parallel converter cable? Might work! Here's an Amazon link...
https://www.amazon.com/parallel-usb-ada ... sb+adapter

[vtpup]

Thanks Wiz, but nope they don't work. There are a couple of very expensive versions that worked with Mach 3 (a discontinued cnc program for Windows) but only that one program. None work with LinuxCNC.

[Wiz57]

Well, my thought was you might could use a bit newer laptop, which mostly have USB ports, no parallel or serial, but with the
converter cable would allow you to use a USB port as a parallel port to connect to the CNC mill. Then install your CNC software
to the newer laptop. Something to consider anyway. Otherwise, finding a decent replacement Thinkpad of same vintage may
be next to impossible or cost prohibitive.

[wizard]

@vtpup

Your 600e had a Pentium 3 CPU (hacked in), the T43 has Pentium M, wonder if you used another Pentium 3 laptop, if it would work better. Is there a list of known working models?

wizard

[vtpup]

Well Wizard, I won't be buying another old laptop for this. I'd like to get the existing one working though if possible. Otherwise it's just a paperweight.

What I could use is some advice on how to either make the present installation work (get rid of the "read-only filesystem" problem which seems to be affecting /var/logs) or,

how to edit a CD ISO and then save it again.

[wizard]

@vtpup

The ISO can probably be started off of a thumb drive, instead of CD, to make it a little quicker to load.

Have you tried this yet? If you can install the ISO to USB and boot, seems it would solve the RO issue.

wizard

[proebler]

@vtpup
Perhaps you can get a HP Elitebook with a docking station.
I have two different ones, one for the 8460p and the other for the 6930p.
Both docking stations have serial and parallel ports. (the laptops don't have the ports)

[rockedge]

@vtpup
It might be as easy as fixing the owner and permissions of the /var/log at least to perhaps get further.

Can you check the permissions for /var/log ?

I made some time ago a Bionicpup32 with a full real time kernel I compiled for it and CNCLinux running on it that a guy in France was using to run a mill and lathe. He had good results using it on a 32 Bit Tower with parallel and serial ports.

So it is possible. It might go with Tahr-6.0.5 with one of my full real time kernels and CNCLinux.

We could try another RT kernel and firmware combination with what you have that almost boots.......

[vtpup]

Wow, thanks guys, a lot of interesting stuff!

@proebler thanks for the suggestion re. another laptop and a docking station. As I said before, I don't want to buy another laptop, or docking station and a docking station wouldn't be removable from the rough environment of the shop.

The Thinkpad T43 will presently run linuxCNC from a CD. What I need to do is modify that install -- either by editing a couple of things on the CD, or installing what's on the CD onto my laptop, and modifying it there. So far I have tried the installation method that Saintless originally suggested, which was basically unsquashing the ISO and placing the folder casper in a free partition, and then modifying grub's menu.lst with a new stanza pointing to the installation. That nearly booted but threw some quickly scrolling error messages re. read-only file system in /var/log when it tried to write log files.

@wizard, re. use ISO off of a thumb drive, instead of CD: no I haven't tried it yet because I would still need first to modify the ISO to add a kernel module, and a config file for my mill. Maybe I'm not understanding, why would putting the ISO onto a thumbdrive solve the read-only filesystem problem. Isn't that related to the ISO form itself, rather then the medium it's on?

@rockedge Hey thanks rockedge! I did think of that misplaced permissions possibility, and I checked /var/log/ properties. It says root,root
and owner has read,write, and exec permissions.
group and world only have read permissions

The log files also list root, root
owner read and write.
group and world read

re. a puppy running LinuxCNC -- a long time dream of mine! However Saintless was unable to get a DebDog working on the TP600E so we went to a chopped down Ubuntu, which did work.

Now on this T43, I don't know -- it's a later computer than the TP600E, so maybe it is more amenable to something other than Ubuntu. That would be great. I'm not an Ubuntu fan, but I can put up with it for a single use computer.

Remember though, if you are thinking about doing something along those lines, remember this is a 32 bit machine.

Thanks for all the suggestions!

[vtpup]

I'm wondering if the permissions thing is an Ubuntu flavored quirk. Maybe root isn't the one trying to write the log files in Ubuntu. There are all kinds of program groups and entities in Ubuntu.

I might have a look at the CD and what groups have permissions for writing logs there.....

[wiak]

Why would the partition created full install be a read only filesystem? It isn't an iso... sounds like hard drive issue. Otherwise, that old saintless advice talked about using a patched initrd so as to allow a frugal install with save persistence. That save mechanism won't be read only either:
https://oldforum.puppylinux.com/viewtop ... 84#p801084

[vtpup]

Why would the partition created full install be a read only filesystem? It isn't an iso... sounds like hard drive issue. Otherwise, that old saintless advice talked about using a patched initrd so as to allow a frugal install with save persistence. That save mechanism won't be read only either:
https://oldforum.puppylinux.com/viewtop ... 84#p801084

Wiak, honestly I don't know why the full install would be a read only filesystem. I was hoping somebody here could explain it to me. But it sounds like it isn't possible.

I was wondering if when Saintless said to add "ro" to the grub menu.lst stanza had anything to do with it, but I tried it without and no change.

I have other hard drives I can easily plug in to check the drive, but the Puppy alternate boot on the existing drive (puppy 432 v3) is set up to do a fsck every boot, and the CNCLinux partition (sda7) is freshly formatted ext3 journaling. I'd be surprised if the hard drive has a problem, but worth checking, I guess.

I'm going to take some photos of the messages when booting from sda7, and of various file permissions in /var when running on the CD, and also a photo of the unsquashing installation process when writing to sda7. Photos because I can't screenshot those particulars while they're moving.

Thank you for any help. Oh also -- re. the saintless patched initrd is no longer available on those linked servers in that post.

[vtpup]

First, the file permissions in /var on my system while it's running LinuxCNC as a liveCD.

[vtpup]

Next, three screens from the startup in the installed version at the end when it aborts:

LinuxCNCFullInstallStartupMessages1.jpg (112.55 KiB) Viewed 969 times

LinuxCNCFullInstallStartupMessages2.jpg (113.07 KiB) Viewed 969 times

LinuxCNCFullInstallStartupMessages3.jpg (106.61 KiB) Viewed 969 times

[vtpup]

I'm in the process of switching out the heard drive, per Wiak suggestion to see if that makes a difference....

[vtpup]

I switched out the hard drive. I created a fresh set of partitions and installed Tahrpup. I wrote a fresh copy of the LinuxCNC on a new DVD in a new USB writer I just got. I verified the checksum of the new DVD against the original ISO. I followed the original saintless instructions, installing it.

I got exactly the same results.

The only other "media" possibility is that the ISO file is bad. I'll verify the checksums after dinner.

[rockedge]

@vtpup Now looking at your screenshots I realize I saw this exact thing a few days ago . I'll have to check to see what I was doing.....

I don't quite remember if I fixed it and how that was done.

[vtpup]

Thanks Rockedge!

ps. MD5sum of the ISO was correct.

[vtpup]

Found this old (14 yrs) blast from the past:

https://forum.linuxcnc.org/9-installing ... uppy-linux

[vtpup]

Well, I'm giving up on LinuxCNC. I'm going to tear out the breakout board in my stepper controller in a few minutes and substitute an Arduino Uno with GRBL firmware. Then I can run easily on any Puppy running on any USB equipped computer that will run any one of a number of available GRBL controller programs. I will give up true real time control, but it looks like GRBL controllers have come a long way since I last tried one about ten years ago that left me somewhat unimpressed for use with a mill. Seemed okay for a 3D printer. But I think now things have changed.

I'm just tired of trying to find the right old-age computer with low latency and a parallel port running the right kernel obsolete Ububntu or Debian Linux in a full install that actually boots.

Time to use my mill to do something!

[Wiz57]

@vtpup
On your new hard drive install, I assume you're using grub4dos or grub2 as bootloader...
if grub4dos, locate the file "menu.lst" as in "menu.list, not the number one st"...open in text editor, check the
line that reads "pmedia=XXX", make sure XXX is something like atahd, or atausb (for save on demand)
It depends on how your Puppy was "installed", but I suspect it used a "pmedia=cdrom" line! This will
tell whatever Pup that the system is booting from a read only CDROM!
If using grub2, look for a file named grub.cfg, look for the same pmedia=XXX line and edit as desired.

[vtpup]

Thanks @Wiz57. I checked and it's grldr and menu.lst on sda1 on the T43 Thinkpad, In the linuxcnc stanza there is no PMEDIA at all. The other stanzas for various puppies do have PMEDIA=idehd

Here is the actual LinuxCNC stanza:

title EMC2
uuid 29221672-c70f-49d7-b02f-6a4ad120c891
kernel /boot/vmlinuz-2.6.24-16-rtai root=UUID=29221672-c70f-49d7-b02f-6a4ad120c891 ro
initrd/boot/initrd.img-2.6.24-16-rtai

[wiak]

I wondered if the issue is something to do with the way your partition is being mounted.

If you run the command mount by itself, you should be able to see the mount status such as if it is ro or rw or nosuid and so on.

I don't know if the partition could be remounted with different status from the already running distro, but I have a recollection that it can, but really I remember very little about such matters.

I was thinking along the lines of using something like:

mount <partition> -o remount,rw

along with whatever mount options you might want, but maybe just assume default will be okay.

I also remembered a different discussion regarding KLV-Airedale rather than Puppy, but had mount permission related problem when trying to use a portable app. No idea if any of this is helpful:

viewtopic.php?p=79901#p79901

[vtpup]

Thanks Wiak.

Unfortunately, mount shows:
/dev/sda7 type ext2 (rw,relatime,errors=continue)

Could it be some missing flag when I unsquashed the ISO, per saintless:

unsquashfs -f -d /mnt/sda7 /path-to/casper/filesystem.squashfs

[vtpup]

I've removed the hard drive from my old TP600e and though the computer is dead, the hard drive is intact and I can now read it with a USB adapter cable. So I can actually see the LinuxCNC installation that worked. I'm going to see if I can use what I find there on the newer Thinkpad T43.

The working stanza in the TP600e grub menu.lst reads:

title Ubuntu 8.04.2, kernel 2.6.24-16-rtai
root (hd0,4)
kernel /boot/vmlinuz-2.6.24-16-rtai root=UUID=4547aabd-29e7-46fe-830c-c7a16fc96973 acpi=off pci=noacpi pnpbios=off nosmp ro quiet splash
initrd /boot/initrd.img-2.6.24-16-rtai
quiet

It also looks like the boot folder was located in sda5 (/mnt/home where frugal Puppies resided) and the boot folder contained:

Screenshot121(1).jpg (35.58 KiB) Viewed 447 times

Which kinda looks like that boot folder contained the linuxCNC installation, itself. There are also apparently test full linux installations on sda2 and sda6, but I don't think they were used or successful. Interesting....

[vtpup]

Well, well, what do you know, the TP43 boots up over USB from the TP600e hard drive, and not only that, runs the LinuxCNC that was installed on it!

So just to preserve that precious 40 gb drive, I just copied it via dd to an 80 gb drive to play with. I replaced the new 80 gb drive into the TP43. So now it's a dedicated cnc machine. It already has the old Kelling Mill configuration I needed, so now I only need to see if I can do the latency kernel mod.

Lots of other stuff on that old drive, including old puppies back to Lupu 528 and Puppy 432 and 411.

I'm also curious why it boots LinuxCNC when we couldn't get that working normally before on this computer.....

[Wiz57]

Excellent! Now, what kinds of work do you do on that CNC mill? Reason I ask...well, when I "retired" from pharmacy, I went to work in a local machine shop!
They don't have CNC mills, just ancient ones, like a broken down Hercules, an old Kerney-Trecker from like 1947 (rebuilt that year from Navy surplus, lol).
Me...I started there running a refurbed Brown & Sharpe #2 single spindle machine, also ran an older B&S 00 machine. The B&S I ran most was refurbed to use servo and some CNC rather than full gear/cam driven. In 2020, I tansferred to running a Citizen A20 6E2 5 axis automatic lathe, then to a Tsugami B850, now back to a Citizen 7F3! I make parts for oil exploration/drilling/pumping etc, as well as various valves, etc. Now I'm not only retired, but I get tired, hehe! The milling dept has 4 Bridgeports and I don't know how many drill presses, but that dept isn't as busy as it once was. The B&S dept has slowed as well. Keeps me busy though, helping the young folks learning about that stuff.

[vtpup]

(Hey Wiz57, I was just about to post the following, when I got notified you'd written the post above before I could post this -- I'll answer you next post!)

I've cleaned up the new 80GB drive after dd-ing the old 40 gb drive to it, removing most of the old puppies and extraneous partitions, and expanding the usable ones. The LinuxCNC installation still runs fine.

I made the rtai kernel module changes mentioned in my first post in this thread to try to solve the bad latency problem on this T43 laptop, and that worked! So I'm pretty sure I can start cutting metal with the mill again using LinuxCNC!

Other notes: on this same hard drive, I tried starting the Win98SE on the first partition, but it won't boot from grub -- gets stuck at "stage 2".

I'd like to replace it with a Win XP partition image that was on the just removed T43 drive. That XP install includes some old proprietary CNC hot wire foam cutting software which I'm not sure I can get a replacement license for. You have to get a new license code from the old one-man shop developer every time you re-install it. So I can't just start a new XP instance with it.

So I'm wondering if I can just dd that one into the sda1 on this present drive. But will that screw up booting for the whole disk? Presently, boot goes to sda5, and that's where /boot/grub/menu.lst is located. There doesn't seem to be anything like grldr in the present non-functional Win98 sda1 partition, and no menu.lst there. The WinXP partition I'd like to put dd there DOES have grldr and menu.lst, so I'm not sure what would happen after a partition replacement.

I guess I could go the other way, and copy the linuxcnc install to the winXP drive. If I could do that with just a regular file copy (not a dd image) and have it work -- that might be a better idea. I guess I would have to change the disk references in grub, but wouldn't that likely be all that was needed to port it over?

[vtpup]

Hey @Wiz57, I actually do lots of manual machining, and so this CNC stuff has fallen into disrepair. But I want to use it now for making a few small parts and some patterns (foam) for casting. The present project is a Stirling type hot air engine that I built 18 years ago, and am now experimenting with by substituting different parts for. Here's a pic of it as originally built:

No83-1.jpg (53.34 KiB) Viewed 371 times

I have been casting and machining since 2002. I am completely self taught, and have built most of my tooling from scratch. I built my own lathe (a Gingery) that year from my own patterns and castings:

LatheandPatterns.jpg (71.7 KiB) Viewed 371 times

About ten years ago I built a second lathe to my own design, also casting almost all of the parts myself. These are photos from construction - I actually don't have a photo of the full lathe, finished. Mainly because the shop I work in is so small that I can't get back far enough to fit it all in a photo!

DSCF0439-800.JPG (108.04 KiB) Viewed 371 times

That shows the Tee slotted boring table that I can bolt a toolpost, or a topslide or any number of other things to.