RPI4 Debian 64bit

(download Raspberry Pi imager program (https://www.raspberrypi.org/downloads/)
(use it to burn rpi4-debian64-rtkernel64.img.xz image from (https://forum.linuxcnc.org/9-installing-linuxcnc/38494-rpi4-debian-64bit))
(connect RPi to wired network, plugin keyboard )
(login as user debian, passwd=debian)
sudo passwd root             (change it to debian)
sudo apt-get -y update
sudo apt-get -y upgrade
sudo reboot
sudo sh /boot/install.sh
       (copied there after flashing the sd card (before booting Pi with it)
       from https://www.raspberrypi.org/forums/viewtopic.php?t=42836, which suggests using
       install.sh from https://github.com/EmilGus/install_raspi-config)
sudo apt --fix-broken install (raspi-config install failed so someone online suggested this and the subsequent --expand-rootfs worked okay)
sudo reboot
(login as debian/debian)
sudo raspi-config --expand-rootfs
sudo reboot
sudo dpkg-reconfigure locales      ( choose en_US.UTF-8 )
sudo dpkg-reconfigure keyboard-configuration
sudo dpkg-reconfigure tzdata       ( choose US/Eastern )
sudo reboot
sudo tasksel                                  ( choose XFCE )
sudo reboot
sudo apt-get install cifs-utils (to mount samba utilities)
sudo mount.cifs //mycomputer/share /home/debian/mnt/lcnc-binaries/ -o user=myusername,pass=<place password here>
cd /home/debian/mnt/lcnc-binaries/.../<path to zip files from (https://forum.linuxcnc.org/9-installing-linuxcnc/38494-rpi4-debian-64bit)
mkdir /home/debian/linuxcnc-install-files
cp linuxcnc-debs-2.8.zip /home/debian/linuxcnc-install-files
cp linuxcnc-mem-services.zip /home/debian/linuxcnc-install-files
cd /home/debian/linuxcnc-install-files
sudo unzip /home/debian/linuxcnc-install-files/linuxcnc-mem-services.zip   -d /etc/systemd/system
unzip linuxcnc-debs-2.8.zip
mv linuxcnc\ debs\ 2.8/ linux-cnc-debs-2.8
sudo mv /etc/systemd/system/mem\ services/set* /etc/systemd/system
sudo rm -rf /etc/systemd/system/mem\ sevices/
sudo systemctl enable setmempermissions.service
sudo systemctl start setmempermissions.service
sudo systemctl enable setgpiomempermissions.service
sudo systemctl start setgpiomempermissions.service
sudo reboot -n
sudo ls -l /dev | more             (looking for mem and gpiomem)
sudo apt install gdebi gdebi-core
sudo gdebi -n /home/debian/linuxcnc-install-files/linux-cnc-debs-2.8/linuxcnc-doc-en_2.8.0~pre1_all.deb
sudo gdebi -n /home/debian/linuxcnc-install-files/linux-cnc-debs-2.8/linuxcnc-uspace_2.8.0~pre1_arm64.deb
sudo reboot
(login to XFCE gui as debian, and run the LinuxCNC Jitter test)