raspberry pi 4 B(RAM 4g and 8g) cant install linuxcnc

I started to buy a Raspberry Pi 4b 8G version, and an error occurred in the error below when installing LINUXCNC at the boot stage. I saw in the official instructions that the 8G version may not be compatible with LINUXCNC, so I bought a 4G version. Now, the error in the error below still appears. I hope someone can help me.
 

We are currently testing this and will update it shortly but there is a set of instructions to install Debian Bookworm for the Pi 4B here 
github.com/rodw-au/linuxcnc/blob/rodw-ge...etting-linuxcnc.adoc
From a session today:
Just change the download link  to
raspi.debian.net/daily-images/
and where we say to use tasksel, instead try 
I don't think an 8gb pi should be an issue but I have no experience

​​​​​​We have tested on 2gb and 4gb so perhaps you can test with your 8gb? (I might add 4gb is enough for Linuxcnc)

Hi I spotted this myself
It's not an issue with the Pi being 8Gb, I have one myself

In the case of the Pi4 it has an eeprom on the board
The eeprom can be updated ether at the factory before it's shipped
or due to a new / current version of raspian running which has then updated the eeprom automatically

If the files within /boot; typically "start*", "fixup*", "bootcode.bin" are out of date (don't match the newer eeprom)
That's what causes the problem.
This wouldn't crop up with running a raspian image normally as the image is updated on a regular basis.
Although the main RPI4 image linked on the linuxcnc site is kinda out of date which causes the problem.

I did create a patched version of the image here with the fixed boot files
lfs.hecatron.com/linuxcnc/linuxcnc-2.8.1-pi4-fwpatched.7z
However it's still quite old and things will break as soon as you try and update any of it (due to it trying to update the kernel)

With that in mind it's probably better to use the links rodw has posted above instead
 

garlicbread wrote:

I did create a patched version of the image here with the fixed boot files
lfs.hecatron.com/linuxcnc/linuxcnc-2.8.1-pi4-fwpatched.7z
However it's still quite old and things will break as soon as you try and update any of it (due to it trying to update the kernel)

With that in mind it's probably better to use the links rodw has posted above instead
 

I have two people experimenting now. Both got to running linuxcnc. One said tasksel was confusing which is resolved with the other command mentioned above. ​​​​I think there are a number of optimisations we can do yet.

The other issue is flickering artefacts on the desktop screen. Any ideas how to fix that?

As far as flickering screens if this is on the Rpi then it might be ether a power supply issue
or a setting within /boot/config.txt in relation to the hdmi video output such as overscan
I've put my own config.txt file here for reference - github.com/Hecatron-Cad/LinuxCNC.Notes/b...pts/setup/config.txt
Some folks use cheap phone charger cables, but the Pi4 needs a bit more current than that ideally.

As far as tasksel I'm afraid I've never used that one, so far I've been using dietPi instead of raw debian or raspian
this means I can use the dietpi-software / dietpi-config tools to install and set up the desktop instead of tasksel
I might also give Armbian a try as well since I've heard it might be used as a basis for the next official image
Although I've not tried out it's setup toolset just yet

I've put together my own set of notes on github - github.com/Hecatron-Cad/LinuxCNC.Notes/tree/master/docs/content
Including a script I pulled from another site that uses irqbalance and tuna to try and isolate cpu's 2 and 3 more
although I'm not sure it makes any difference at this stage.
 

Thanks for that.
Yes when I googled the screen issue is usually crappy power or HDMI cable.
isolcpus can be set in boot.txt and do make a difference.

These are the settings I have gleaned from other threads as additions to config.txt

Armbian is quite cool but you'll probably have to use their armbian-build to compile the PREEMPT_RT kernel to get the patches in.
First build a normal image to configure the build environment. Then copy the patches you want into the right folder under /userpatches
At this point assuming a bootable image, just build the Debs as its a lot quicker. INstall with dpkg -i

Thank you guys very much. I successfully used this ISO  lfs.hecatron.com/linuxcnc/linuxcnc-2.8.1-pi4-fwpatched.7z to enter the Rpi 4b 8G version into the system today, but I still have several other projects to do, So I have to work on others, I will test later and find out the error reason, and then I will contact you or help others who have the same problem with me.

When I looked at /boot/config.txt within that image I did noticeSo that should cover it.

It's an issue that's been fixed within later kernels I think (or at least I've not seen it on 6.3)
But the kernel version in that image is much older.
 

Thank you very much, I have successfully realized my original plan, Linuxcnc + raspberry pi + ethercat, thank you very much.