2.6 from LiveDVD - > New latency problems.

We have a Dell machine that is running the LinuxCNC V2.5 installed from the last CD based LiveCD (Ubuntu based)
Latency test report a jitter of ~5000ns.

We installed along side of it the new hybrid 2.6 version (Debian based) .
Latency test report a jitter of ~400,000ns.

The Stepconfig Axis test seems to run the machine smoothly but when running LinuxCNC we get bad grinding noise and the motors do not run smooth. (I assume it is the latency issue)

How do I start figuring this out ?

Thanks.

-Doron

it's probably due to the mix and something has screwed up.
install the hybrid to a fresh drive , and see

i'm using the hybrid on 3 machines without probs as far as latency
but mixing repro's is perhaps not a good idea

Hi

We installed along side of it the new hybrid 2.6 version (Debian based) .

I presume you mean on another partition?

The Stepconfig Axis test seems to run the machine smoothly

If you have a working config, why have you created a new one? Use the old one.

....................but when running LinuxCNC we get bad grinding noise and the motors do not run smooth. (I assume it is the latency issue)

What gives really rough grinding noise and slow movement, is often the stepper timings far too short.
Have you entered us values in the fields that are ns in stepconf?

Back to the original config, try using that.

regards

We are using the same configuration values as for 2.5 so its not the slow speed or timing but rather the 04ms jitter (movement is very rough)

We have tried to do a fresh install on a new drive...got same results.

We reverted to 2.5 on Ubuntu for now but it might be worth while to sort it out.

(FYI : on another Dell machine we have with a smaller CNC, we had no problems with 2.6)

cncbasher wrote:

it's probably due to the mix and something has screwed up.
install the hybrid to a fresh drive , and see

i'm using the hybrid on 3 machines without probs as far as latency
but mixing repro's is perhaps not a good idea

We have tried it to a fresh drive and to a separate partition with identical BAD results.

andypugh wrote:

I would go back to the 2.5 LiveCD then upgrade LinuxCNC _only_ to 2.6

There may be technical interest in figuring out the problem, but if you want a working system then there is no problem with running 2.6 on 10.04 + RTAI.

That machine has no internet access. Can you point us to How do we upgrade to 2.6 from DVD or USB?

Hi

If you have done an install to another computer and it works fine, I should just forget about it, there is obviously something basically incompatible with that machine.

That machine has no internet access. Can you point us to How do we upgrade to 2.6 from DVD or USB?

You just download the packages, put them on a USB stick, remove the old packages and install the new ones, using dpkg.

Machine with internet fetch these
linuxcnc.org/dists/lucid/2.6/binary-i386...uxcnc_2.6.2_i386.deb
linuxcnc.org/dists/lucid/2.6/binary-i386...c-dev_2.6.2_i386.deb

copy to USB

Host machine
sudo dpkg -r linuxcnc-dev
sudo dpkg -r linuxcnc

sudo dpkg -i -linuxcnc_2.6.2_i386.deb
sudo dpkg -i -linuxcnc-dev_2.6.2_i386.deb


Lemon squeezy

ArcEye wrote:

Hi

If you have done an install to another computer and it works fine, I should just forget about it, there is obviously something basically incompatible with that machine.

That machine has no internet access. Can you point us to How do we upgrade to 2.6 from DVD or USB?

That machine has been running 2.5 just fine.... We have no other machine to keep at that location....
I will try to manually upgrade just the 2.6 files with the older Ubuntu.
Do we need to copy the 2 files from the USB stick to any specific location for the rest of your instructions to work ?

Thanks.
-D

Do we need to copy the 2 files from the USB stick to any specific location for the rest of your instructions to work ?

No, you just have to be in that location when you issue the dpkg -i command or it will not find them

regards