Tested on Raspberry pi 3B+, Pi 4B, Pi400
1) Download from
www.raspberrypi.com/software/operating-s...spberry-pi-os-legacy
a image of stable legacy version of Raspberry Pi OS Buster
and install to an SD card (with Raspberry Pi Imager or similar)
2) Update OS
Code:
sudo apt update
sudo apt upgrade
3) Install the realtime kernel (5.15.65-rt49)
As reported in
github.com/kdoren/linux/releases
Code:
sudo su
cd /tmp
wget https://github.com/kdoren/linux/releases/download/rpi_5.15.65-rt49/linux-image-5.15.65-rt49-v7l+_5.15.65-1_armhf.deb
apt install ./linux-image-5.15.65-rt49-v7l+_5.15.65-1_armhf.deb
KERN=5.15.65-rt49-v7l+
mkdir -p /boot/$KERN/o/
cp -d /usr/lib/linux-image-$KERN/overlays/* /boot/$KERN/o/
cp -dr /usr/lib/linux-image-$KERN/* /boot/$KERN/
[[ -d /usr/lib/linux-image-$KERN/broadcom ]] && cp -d /usr/lib/linux-image-$KERN/broadcom/* /boot/$KERN/
touch /boot/$KERN/o/README
mv /boot/vmlinuz-$KERN /boot/$KERN/
mv /boot/initrd.img-$KERN /boot/$KERN/
mv /boot/System.map-$KERN /boot/$KERN/
cp /boot/config-$KERN /boot/$KERN/
cp /boot/cmdline.txt /boot/$KERN/
cat >> /boot/config.txt << EOF
[all]
kernel=vmlinuz-$KERN
# initramfs initrd.img-$KERN
os_prefix=$KERN/
overlay_prefix=o/$(if [[ "$KERN" =~ 'v8' ]]; then echo -e "\narm_64bit=1"; fi)
[all]
EOF
4) Optimizing kernel (
gnipsel.com/linuxcnc/rpi4-11-emc.html
)
Code:
sudo nano /boot/$KERN/cmdline.txt
Add 'isolcpus=1,2,3 idle=poll' to the end of the string then press Ctrl x, y, Enter
Logout and Reboot
5) Install LinuxCNC
Boot the Pi and open a terminal
Add the LinuxCNC Archive Signing Key to your apt keyring
Code:
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com --recv-key 3cb9fd148f374fef
Add the apt repository:
(
linuxcnc.org/docs/html/getting-started/g...th_preempt_rt_kernel
)
Code:
echo deb http://linuxcnc.org/ buster base 2.8-rtpreempt | sudo tee /etc/apt/sources.list.d/linuxcnc.list
echo deb-src http://linuxcnc.org/ buster base 2.8-rtpreempt | sudo tee -a /etc/apt/sources.list.d/linuxcnc.list
Update the package list from linuxcnc.org
Code:
sudo apt-get update
sudo apt-get install linuxcnc-uspace linuxcnc-uspace-dev
The image is downloadable at this link:
linucnc-2.8.4-buster_armhf_rt.zip
