Debian 10 Buster PREEMPT-RT ISO

Hello,

I am a German user and have been running a milling machine with Linux-EMC (first very old Ubuntu and now an old Debian Hybrid-ISO) on the parallel port for a few years.
Works also so far everything smoothly.
Now it is so that I can no longer update the old Linux operating system and would like to integrate the computer into the network.

I have now read that there is a new ISO on Debian 10 basis.
Link:
linuxcnc.org/downloads/

Quickly made a Linux USB stick with it and installed on the same computer but new hard drive.
Installation has worked so far.
Unfortunately this ISO is based on the PREEMPT-RT patch and I have a high latency of 50000. With the former
RTAI kernel only about 27000. So I could work very well.
In the manual
Link:
linuxcnc.org/docs/2.8/html/getting-start...#cha:Installing-RTAI

it says how to update to a RTAI kernel.
Unfortunately the manual is not correct anymore.
The command

sudo apt-get install linuxcnc

leads to nothing. There is no package linuxcnc.

Yes I know that this kernel and the associated linuxcnc is experimental. But then you should remove that from the instructions.

What bothers me a lot are the many manuals in the internet that refer to outdated Linux (EMC) distributions. When I set up my machine years ago, it was a cramp to get the right information. As it seems nothing has changed. You can always find a piece here and there.
Maybe the authors should exclude old or even better call a new page into life where really only the newest is to be found.

I installed the new image on an industrial mainboard Kontron D3543-S with J5005 CPU. But it also has a latency of about 50000.
Also it only allows installation in UEFI mode. Old Linux images are not possible.

Ok, but that does not help me now. Does anyone have an idea how to get to the RTAI kernel?

What about Debian Bullseye and RTAI kernel in the future? Makes sense, since it includes a 5 year support and is quite current.


Sincerely. Max


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Hello,


Yes I copied all the commands and ran them in the terminal.
The package sources were also updated.
Only the last command sudo apt-get install linuxcnc brought an error message that this package is missing.
I restarted the computer and started synaptic to see if the package linuxcnc is present. But it is not.

can anyone confirm this?

MfG. 

Thanks andypugh,

Everything works through this link.
I can now install LinuxCNC without any problems. This also installs the RTAI kernel.
Also the latency was reduced from almost 50000 to 32000.

I was of course interested why it does not work with the original instructions
Link:  linuxcnc.org/docs/2.8/html/getting-start...#cha:Installing-RTAI

I found that the command

echo deb linuxcnc.org/ buster base 2.8-rt | sudo tee /etc/apt/sources.list.d/linuxcnc.list
creates a new linuxcnc.list.

If you now use the command:
echo deb-src linuxcnc.org/ buster base 2.8-rt | sudo tee /etc/apt/sources.list.d/linuxcnc.list
the linuxcnc.list you just created will be regenerated.
The line is then missing 
"echo deb linuxcnc.org/ buster base 2.8-rt | sudo tee /etc/apt/sources.list.d/linuxcnc.list"

If you enter both lines like the link from you and save everything works.

Can it be that in the manual a wrong syntax was written.

MfG

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Thanks now it works.

What always amazes me that no one says anything.
Even the creator of this documentation should check something like that again.