LinuxCNC Uspace

it gets bigger and bigger
i hope bigT will get lubuntu on the system soon

I wanted to update here that I was able to install the preempt kernel from the debian repo on my actual mint 19.1 computer. I've also managed to compile, configure, and run linuxcnc 2.9. All appears to be working as expected with the debian repo's kernel.

AgentWD40 wrote: Is the 4.9 kernel suitable? John's instructions are for the 4.19 kernel.

I've been doing some testing on my J1900 and the kernel you use seems to be dependent on the CPU. For example on the J1900 an older CPU 5.> the servo thread latency is ~250us, 4.19 is ~150us, 4.4 gives me ~50us. So picking the best kernel version depends on your hardware and may require some testing.

After building a few kernels I wrote a bash scrip to automate the unpacking and patching process.
gnipsel.com/linuxcnc/uspace/latency.html

Make sure you run the script as source, this means in the terminal it's dot space dot slash . ./rt.sh

JT

AgentWD40 wrote: I wanted to update here that I was able to install the preempt kernel from the debian repo on my actual mint 19.1 computer.

It is probably worth documenting exactly how you did this.


Experimenting, I thought that I might have found an easy recipe for getting a realtime kernel:
This appears to work on an existing Stretch 4.9.0-9 kernel installation, but failed on Jessie. (but Jessie uses a 3.x kernel)
YMMV.

andypugh wrote:

AgentWD40 wrote: I wanted to update here that I was able to install the preempt kernel from the debian repo on my actual mint 19.1 computer.

It is probably worth documenting exactly how you did this.

Andy, your recipe looks much easier than mine! But for what it's worth here is what I did:

From a fresh install of Mint 19.1 Mate edition.

Go to Synaptic Package Manager -> Settings -> Repositories -> Additional Repositories -> Add
Click Ok and exit the package manager.

If I run sudo apt-get update now it will throw some errors about missing keys for the debian repo. If I try to update from Synaptic it fails and doesn't tell me why. From the terminal I got an error message that displayed exactly which keys I needed, they were 8B48AD6246925553, 7638D0442B90D010, and EF0F382A1A7B6500.

So from the terminal run these commands to install those keys, the kernel and install grub customizer while I'm at it:

Launch grub-customizer
In the list configuration tab find the new rt kernel, in my case it says "Ubuntu, with Linux 4.9.0-9-rt-amd64". Select it then use the arrow keys in the toolbar to move this entry to be the first listed kernel under the "Advanced options for Ubuntu" folder. I tried setting the default entry under the General settings tab but that didn't seem to work.

After I was done customizing grub click save and make sure to wait for the save to complete. Reboot and check that it worked by running 'uname -a' in the terminal to see which kernel is loaded.

At this point I went back to the Synaptic Package Manager and disabled the debian repo. I assume packages in the mint repo would take precedence but I didn't want to take the chance of creating conflicts so it's disabled for now.

AgentWD40 wrote:

andypugh wrote:

AgentWD40 wrote: I wanted to update here that I was able to install the preempt kernel from the debian repo on my actual mint 19.1 computer.

It is probably worth documenting exactly how you did this.

Andy, your recipe looks much easier than mine! But for what it's worth here is what I did:

From a fresh install of Mint 19.1 Mate edition.

Go to Synaptic Package Manager -> Settings -> Repositories -> Additional Repositories -> Add

Code:

deb http://deb.debian.org/debian stretch main

Click Ok and exit the package manager.

If I run sudo apt-get update now it will throw some errors about missing keys for the debian repo. If I try to update from Synaptic it fails and doesn't tell me why. From the terminal I got an error message that displayed exactly which keys I needed, they were 8B48AD6246925553, 7638D0442B90D010, and EF0F382A1A7B6500.

So from the terminal run these commands to install those keys, the kernel and install grub customizer while I'm at it:

Code:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 8B48AD6246925553 7638D0442B90D010 EF0F382A1A7B6500 sudo add-apt-repository ppa:danielrichter2007/grub-customizer sudo apt-get update sudo apt-get install linux-image-rt-amd64 sudo apt-get install grub-customizer

Launch grub-customizer

Code:

grub-customizer

In the list configuration tab find the new rt kernel, in my case it says "Ubuntu, with Linux 4.9.0-9-rt-amd64". Select it then use the arrow keys in the toolbar to move this entry to be the first listed kernel under the "Advanced options for Ubuntu" folder. I tried setting the default entry under the General settings tab but that didn't seem to work.

After I was done customizing grub click save and make sure to wait for the save to complete. Reboot and check that it worked by running 'uname -a' in the terminal to see which kernel is loaded.

At this point I went back to the Synaptic Package Manager and disabled the debian repo. I assume packages in the mint repo would take precedence but I didn't want to take the chance of creating conflicts so it's disabled for now.

Nice work!!!

bevins wrote: Andy, your recipe looks much easier than mine!

Maybe, but simple is no good if it doesn't work.

But for what it's worth here is what I did:

Thanks.

In trying to update OpenGL drivers so I can run qtpyvcp, I totally borked my whole system so I did a fresh install of debian 10 (buster) as stretch seems no longer available. Trying to install linuxcnc-uspace has several unmet dependencies which I am unable to resolve. Will the instructions be updated any time soon to include buster? If not, I can go back to stretch (I hope).

Don't know how "soon" but I did download Debian 10 this morning.

Try using the VTK display widget instead of the Gremlin display widget.

JT

When I posted, I didn't realize buster was only released a couple days prior, so of course it is completely unreasonable to expect you to be on it already. I redid a fresh install of stretch using your excellent instructions and everything is restored. Thankfully, I make periodic backups.