RPI4 Raspbian 64 bit & LinuxCNC

cakeslob wrote:

Trying to test out the new image elovalvo, your work is appreciated, but just a few comments
For some reason, every image I download from you (this is the 4th so far), it says the image is corrupted when I unpack the rar files. Ive even redownloaded and it still says corrupted but images appear to load fine.
Unpacked, this image is 8gb so it takes a long time to load it to sd card, I think it took me like 3-4 hours or something.
Lastly, what power supply/setup are you using? When I load the 2.9pre_rt64a on my setup it is incredibly power hungry. it boots the os, but trying to do anything causes huge latency spikes related to not enough voltage. I can assume the improved latency is related to the power draw, but ive only been able to successfully run these images on a CM4 with 12v power supply. this newest one with even latency improved even more(2.9pre_rt64b), I cannot fully boot to os on 2 of my setups so far(normal RPI4). I will try a few more later today, and report back.
That being said, I have had unwavering success with the 32bit 5.4 images you posted some time ago, and have it loaded on several of my setups without issue. Thank you for your work.

Dear cakeslob,
I preferred to use a complete image (and therefore inevitably large) to avoid having to redo a series of commands that are reported in the first post of the topic and that allow you to change the 64-bit operating system with the Preempt_rt and load the version of LinuxCNC compatible with this.

In any case, the image is ZIP-ped and not RAR-red, so as to be able to use the Raspberry Pi Imager directly without unpacking the archive.

Even for the installation I did not have the problems that you report.
I used a common PC with the Raspberry Pi Imager using a USB 3.0 card reader with an SD card at least class 10.
The procedure in this case takes about 10-15 min.

The power supply, as reported in
www.raspberrypi.org/products/raspberry-p...el-b/specifications/
must provide a power of at least 3 Amps.
Check your power supply.
 

My power supplies are alright, its just a noticeable difference from 32bit images so I was curious , but it appears Ive been wasting a lot of time unziping these images, thank you

Hi All

I have "succesfully" installed the image that Elovalvo mentioned above on a RPI4B-8G unit, but my values are not very good, not to say terrible.
Trying to speed up the boot process, I installed the system on the SD card, and then moved it to a 128GB SSD M.2 disk, running it from there.

Running "top" from command line - I'm barely getting below 2.50 and have seen numbers of 4.60.
Latency tests don't go below 100000ns - But i have seen values above 250000!
That said, latency is not my biggest concern, since I am going to use a 7i76e to control my mill,- but even then - numbers as big as 250000 - would that even work ?

I haven't connected the mesa board yet, since my dell 2418HT touch monitor is also bugging me. It's a very fine monitor, but I have a 1/2 inch black frame all way around the desktop, and I can't auto adjust the monitor, no to talk about thew flickering i sometimes get on the lower 1/4 part of the screen (but that's only when I use the attached mouse - which will be disconnected once touch is fully working).
According to this link - Dell 2814HT with Raspberry Pi 4 - the 2418HT should be working with RPI4, but maybe it's the LinuxCNC distro that needs tweaking..?
Also still working on getting the touch screen calibrated to actually point where I touch.

My biggest concern at the moment is the performance of the system though.
Aside testing different IsolCPUs settings, what else could i tweak on to get better performance ?

Any input is highly valued!

Thanks in advance

I was able to lower my latency a good bit by disabling Bluetooth and wifi. And if you need more turn off audio.
My latency also got a bit better after giving it an overclock.

Disabling wifi and bluetooth really helped.
I am now getting numbers steady at 105000,- with 7 x glxgears running.
Starting youtube pushed it straight to 250000, but hen again - I won't be running youtube on this machine when its done. It pure CNC.
Without glxgears and youtube, I'm steady below 80000 - which should be fine accoring to Andypugh's comment
Enabling overclock actually just made it a lot worse - so i'm sticking with the above.
Thanks for the help
Also found a thread about the black border. It suggested that disabling overscan could solve it.
Gonna check that out later today.

interesting that the overclock made it much worse.
did you not only increase the clock but also voltage and gpu clock?
Also the RPi4 runs hot stock so a small 1" heatsink plus fan helps a ton.

Hello, 

I have successfully built the 5.10 RT kernel as well as compiled linuxcnc on a RPi with 64bit Raspbian. Axis GUI is working as well. However when I try to start Gmoccapy I get the following error: 

This looks to me like the python-gtksourceview2 module is missing. So I tried to install it with

This fails with the following message: 
But on the the 32bit version of Raspbian the package is available. 

Is the problem really linked to this missing package. If so, how can I solve this?

Best regards, 

Marc


 

As mentioned in the first post of this thread, 
forum.linuxcnc.org/9-installing-linuxcnc...uxcnc?start=0#178299

you can solve the problem like this:

cd ~/
wget ftp.it.debian.org/debian/pool/main/p/pyg...2_2.10.1-3_arm64.deb
sudo dpkg -i python-gtksourceview2_2.10.1-3_arm64.deb
sudo apt --fix-broken install

Thanks a lot! Missed that one...