RPI3: Difference between revisions

From DaqWiki
Jump to navigation Jump to search
 
(15 intermediate revisions by the same user not shown)
Line 3: Line 3:
= Links =
= Links =


* AAA
* https://downloads.raspberrypi.org/raspios_full_armhf/release_notes.txt


= On-board hardware =
= On-board hardware =
Line 162: Line 162:
= cmdline.txt =
= cmdline.txt =


AAA
cmdlinux.txt provides the linux kernel command line parameters.
 
* rpi3-boot-4.4.21-v7+/cmdline-mmcblk.txt - boot from SD card
<pre>
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
</pre>
* rpi3-boot-4.4.21-v7+/cmdline-nfsroot.txt - boot from NFS
<pre>
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 ip=dhcp rw root=/dev/nfs elevator=deadline panic=60
</pre>
* rpi3-boot-5.10.17-v7+/cmdline-mmcblk.txt - boot form SD card
<pre>
console=serial0,115200 console=tty1 root=PARTUUID=641f3e0d-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles
</pre>
* rpi3-boot-5.10.17-v7+/cmdline-nfsroot.txt - boot from NFS
<pre>
console=serial0,115200 console=tty1 elevator=deadline ip=dhcp rw root=/dev/nfs panic=60
</pre>


= Create bootable CentOS7 SD card =
= Create bootable CentOS7 SD card =
Line 208: Line 225:
* make it bootable (see instructions above, select cmdlinux-mmcblk.txt)
* make it bootable (see instructions above, select cmdlinux-mmcblk.txt)
* add the Raspbian userland (follow CentOS-7 instructions above, but rsync Raspbian image instead of CentOS-7 image)
* add the Raspbian userland (follow CentOS-7 instructions above, but rsync Raspbian image instead of CentOS-7 image)
= Network-boot Raspbian =
Prepare the boot server in the usual way:
* setup dhcpd or dnsmasq to serve the IP address and the NFS-Root mount path for the userland image
* tftp is not used, is not needed
* setup NFS server to permit mounting the userland image. in /etc/exports have this:
<pre>
/zssd1tb/nfsroot @xxx_netgroup(rw,no_root_squash,async)
</pre>
* do not forget to enable dhcpd/dmsmasq and NFS to start on boot
* do not forget to run "exportfs -rv" and "systemctl restart dhcpd" after making any changes
Prepare a bootable SD card
* use SD card of any size (8 GB or bigger)
* follow instructions to make it bootable
* select cmdline-nfsroot.txt
<pre>
console=serial0,115200 console=tty1 ip=dhcp rw root=/dev/nfs panic=60
</pre>
Install bootable SD card into RPi, power up, and observe:
* RPi boots linux kernel
* linux kernel starts
* makes DHCP request, receives answer
* RPi pings
* RPi mounts the NFS-Root filesystem as specified by DHCP
* RPi OS boots normally
* there is a login prompt
* from boot server, RPi pings and ssh'es.


= Setup Python i2c tools =
= Setup Python i2c tools =
NOTE: DO NOT DO THIS!


<pre>
<pre>
Line 223: Line 272:


= Enable i2c drivers =
= Enable i2c drivers =
NOTE: DO NOT DO THIS!


<pre>
<pre>
Line 393: Line 444:
= I2C =
= I2C =


* if there is no /dev/i2c*, edit /boot/config.txt, uncomment "dtparam=i2c_arm=on", reboot
* if there is no /dev/i2c*:
** mount /dev/mmcblk0p1 /boot
** edit /boot/config.txt, uncomment "dtparam=i2c_arm=on"
** run "echo i2c_dev >> /etc/modules-load.d/i2c_dev.conf"
** umount /boot
** reboot
** after reboot check that i2c_dev and i2c_bcm2835 modules are loaded:
<pre>
root@lvdb04:~# lsmod | grep i2c
i2c_dev                20480  0
i2c_bcm2835            16384  0
root@lvdb04:~#
</pre>
* if no permission to open /dev/i2c*:
** edit /etc/group, add your user to group "i2c", for example:
<pre>
root@lvdb04:~# grep i2c /etc/group
i2c:x:998:pi,agdaq
root@lvdb04:~#
</pre>
** logout, login again (/etc/group is applied at login time)
* apt-get install python-smbus i2c-tools
* apt-get install python-smbus i2c-tools
* i2cdetect -y 1 ### found device at address 0x70:
* i2cdetect -y 1 ### found device at address 0x70:
Line 427: Line 498:
   
   
[[File:Rpi3 rs232 3 3v.jpg|thumb|Rpi3 RS233 3.3V wiring with a standard TTL-232R to USB serial cable (FTDI chip)]]
[[File:Rpi3 rs232 3 3v.jpg|thumb|Rpi3 RS233 3.3V wiring with a standard TTL-232R to USB serial cable (FTDI chip)]]
= Update RPi firmware =
!!! check that SD card is mounted as /boot/firmware !!!
<pre>
apt update
apt upgrade ### install latest eeprom
rpi-eeprom-update -a
</pre>
= RPi4 boot from network =
* run raspi-config, in advanced options, set boot order to network-first
* reboot
* check that the change took
<pre>
root@magpi03:~# vcgencmd bootloader_config
[all]
BOOT_UART=0
WAKE_ON_GPIO=1
POWER_OFF_ON_HALT=0
[all]
BOOT_ORDER=0xf21
</pre>
* shutdown, power off the RPi4
* remove SD card
* power up
* tail -100f /var/log/syslog
* observe RPi4 does DHCP and requests files from /tftpboot/SERIALNUMBER/
* give it files it want, copy the from the SD card /boot/firmware
* copy all of /boot/firmware/overlays to /tftpboot/...
* symlink kernel8.img and initramfs8 to files in /nfsroot/
* should have this:
<pre>
root@haicudaq01:~# ls -l /tftpboot/c914e0e6/
total 1732
-rwxr-xr-x 1 root root  56112 Nov 26 15:43 bcm2711-rpi-4-b.dtb
-rwxr-xr-x 1 root root      70 Nov 26 15:43 cmdline.txt
-rwxr-xr-x 1 root root    1245 Nov 26 15:40 config.txt
-rwxr-xr-x 1 root root    5456 Nov 26 15:42 fixup4.dat
lrwxrwxrwx 1 root root      27 Nov 26 15:47 initramfs8 -> /nfsroot/magpi03/initrd.img
lrwxrwxrwx 1 root root      24 Nov 26 15:47 kernel8.img -> /nfsroot/magpi03/vmlinuz
drwxr-xr-x 2 root root    339 Oct 22 06:05 overlays
-rwxr-xr-x 1 root root 2259296 Nov 26 15:37 start4.elf
root@haicudaq01:~#
</pre>
* cycle power on the RPi4, it should boot from the network (SD card removed)
* not so fast. it did not boot all the way, ssh does not work.
* go to /nfsroot/magpi03/etc/fstab, edit /boot/firmware to have "nofail" otherwise boot will stall at mounting the removed SD card:
<pre>
/dev/mmcblk0p1  /boot/firmware  vfat    defaults,nofail          0      2
</pre>
* cycle power on RPi4 again, now it should boot all the way to ssh
* ssh magpi03
* disable swap (swap to NFS does not/cannot work)
<pre>
systemctl stop dphys-swapfile
systemctl disable dphys-swapfile
rm /var/swap
</pre>
* done


= End =
= End =

Latest revision as of 16:06, 26 November 2024

Raspberry Pi3

Links

On-board hardware

  • AAA

Serial console

there is no useful serial console

Benchmarks

[root@armdaq05 ~]# uname -a
Linux armdaq05.triumf.ca 4.4.21-v7+ #911 SMP Thu Sep 15 14:22:38 BST 2016 armv7l armv7l armv7l GNU/Linux
[root@armdaq05 ~]# cat /proc/cpuinfo 
processor	: 0
model name	: ARMv7 Processor rev 4 (v7l)
BogoMIPS	: 38.40
Features	: half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x0
CPU part	: 0xd03
CPU revision	: 4

processor	: 1
model name	: ARMv7 Processor rev 4 (v7l)
BogoMIPS	: 38.40
Features	: half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x0
CPU part	: 0xd03
CPU revision	: 4

processor	: 2
model name	: ARMv7 Processor rev 4 (v7l)
BogoMIPS	: 38.40
Features	: half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x0
CPU part	: 0xd03
CPU revision	: 4

processor	: 3
model name	: ARMv7 Processor rev 4 (v7l)
BogoMIPS	: 38.40
Features	: half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32 
CPU implementer	: 0x41
CPU architecture: 7
CPU variant	: 0x0
CPU part	: 0xd03
CPU revision	: 4

Hardware	: BCM2709
Revision	: a22082
Serial		: 00000000852ec765
[root@armdaq05 ~]# 
[root@armdaq05 ~]# ./memcpy_arm 
memcpy       1 KiBytes:    710 MB/sec
memcpy       2 KiBytes:   1037 MB/sec
memcpy       4 KiBytes:   1340 MB/sec
memcpy       8 KiBytes:   1572 MB/sec
memcpy      16 KiBytes:   1703 MB/sec
memcpy      32 KiBytes:   2010 MB/sec
memcpy      64 KiBytes:   1780 MB/sec
memcpy     128 KiBytes:   1808 MB/sec
memcpy     256 KiBytes:   1421 MB/sec
memcpy     512 KiBytes:    971 MB/sec
memcpy    1024 KiBytes:    862 MB/sec
memcpy    2048 KiBytes:    824 MB/sec
memcpy    4096 KiBytes:    862 MB/sec
memcpy    8192 KiBytes:    817 MB/sec
memcpy   16384 KiBytes:    797 MB/sec
memcpy   32768 KiBytes:    767 MB/sec
memcpy   65536 KiBytes:    765 MB/sec
memcpy  131072 KiBytes:    766 MB/sec
[root@armdaq05 ~]# 

Original boot files with the CentOS 7.1 userland

NOTE: CentOS-7 userland is now obsolete. use Raspbian userland instead!

[root@armdaq05 ~]# blkid
/dev/mmcblk0p1: SEC_TYPE="msdos" LABEL="boot" UUID="70F7-FA1D" TYPE="vfat" 
/dev/mmcblk0p2: LABEL="el7" UUID="0ca625c5-8db1-4f78-a9fd-e6cce04f399e" TYPE="ext4" 
/dev/mmcblk0: PTTYPE="dos" 
[root@armdaq05 ~]# 
[root@armdaq05 ~]# fdisk -l

Disk /dev/mmcblk0: 31.4 GB, 31439454208 bytes, 61405184 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x5a7089a1

        Device Boot      Start         End      Blocks   Id  System
/dev/mmcblk0p1            8192      137215       64512    c  W95 FAT32 (LBA)
/dev/mmcblk0p2          137216     2713599     1288192   83  Linux
[root@armdaq05 ~]# 
[root@armdaq05 ~]# df -kl
Filesystem     1K-blocks    Used Available Use% Mounted on
/dev/root        1235136 1029272    125072  90% /
devtmpfs          469536       0    469536   0% /dev
tmpfs             473868       0    473868   0% /dev/shm
tmpfs             473868   29964    443904   7% /run
tmpfs             473868       0    473868   0% /sys/fs/cgroup
tmpfs              94776       0     94776   0% /run/user/0
/dev/mmcblk0p1     64456   21192     43264  33% /mnt/tmp
[root@armdaq05 ~]# 

Create bootable SD card

Original boot files are in daqstore:/daq/daqstore/olchansk/daq/RPI3:

rpi3-boot-4.4.21-v7+
rpi3-boot-5.10.17-v7+
  • use 32GB micro-SD flash
  • connect to USB-to-SD flash adapter, plug into linux computer
  • login as root
  • identify the /dev/sdXXX device corresponding to target media: use "fdisk -l", look for a 32GB disk with a single MS-DOS partition
  • ensure the partitions of /dev/sdXXX are not mounted, use "df -kl" and umount /dev/sdXXX1, etc.
  • run "fdisk /dev/sdXXX"
  • create MSDOS partition table: command "o"
  • create first partition 64Mbytes: command "n", primary "p", first sector "<enter>", last sector: "+64M"
  • set partition type "C": command "t", partition 1 is selected automatically, hex code "c"
  • mark bootable: command "a", partition 1 is selected automatically
  • confirm correct layout: command "p"
Disk /dev/sde: 31.1 GB, 31104958464 bytes, 60751872 sectors
   Device Boot      Start         End      Blocks   Id  System
/dev/sde1   *        2048      133119       65536    c  W95 FAT32 (LBA)
  • save new partition table: command "w", there should be no messages other than "syncing disks"
  • mkfs.msdos /dev/sdXXX1
  • mkdir -p /mnt/tmp
  • mount /dev/sdXXX1 /mnt/tmp, cd /mnt/tmp
  • rsync -av /daq/daqstore/olchansk/daq/RPI3/rpi3-boot-XXX/ .
  • sync
  • select boot method:
    • cp cmdline-mmcblk.txt cmdline.txt ### to boot from SD flash
    • cp cmdline-nfsroot.txt cmdline.txt ### to boot from network (dhcp and nfsroot)
  • sync
  • cd /; umount /mnt/tmp
  • eject /dev/sdXXX
  • try to boot from the SD flash - on HDMI video, should see Linux kernel boot all the way to a panic on failure to mount rootfs.

cmdline.txt

cmdlinux.txt provides the linux kernel command line parameters.

  • rpi3-boot-4.4.21-v7+/cmdline-mmcblk.txt - boot from SD card
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
  • rpi3-boot-4.4.21-v7+/cmdline-nfsroot.txt - boot from NFS
dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 ip=dhcp rw root=/dev/nfs elevator=deadline panic=60
  • rpi3-boot-5.10.17-v7+/cmdline-mmcblk.txt - boot form SD card
console=serial0,115200 console=tty1 root=PARTUUID=641f3e0d-02 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles
  • rpi3-boot-5.10.17-v7+/cmdline-nfsroot.txt - boot from NFS
console=serial0,115200 console=tty1 elevator=deadline ip=dhcp rw root=/dev/nfs panic=60

Create bootable CentOS7 SD card

NOTE: CentOS-7 userland is now obsolete. Use Rapsbian userland instead!!!

  • use a 32 GB micro-SD flash card
  • go through the steps to create a bootable SD flash card (see above)
  • connect and identify /dev/sdXXX same as above
  • ensure all partitions are unmounted, same as above
  • create second partion of maximum size:
  • fdisk /dev/sdXXX
  • command "n", "p", enter, enter
  • command "p" to see the layout:
Disk /dev/sde: 31.1 GB, 31104958464 bytes, 60751872 sectors
   Device Boot      Start         End      Blocks   Id  System
/dev/sde1   *        2048      133119       65536    c  W95 FAT32 (LBA)
/dev/sde2          133120    60751871    30309376   83  Linux
  • command "w" to save the changes
  • if it complains about "Device or resource busy":
    • eject /dev/sdXXX
    • remove it from usb adapter
    • connect to usb adapter and identify device again, same as above
  • ls -l /dev/sdXXX* to see there are two partitions "1" and "2"
  • mkfs.ext4 /dev/sdXXX2
  • mkdir -p /mnt/tmp
  • mount /dev/sdXXX2 /mnt/tmp, cd /mnt/tmp
  • rsync -av /ladd/data0/backup.os/armdaq06/ .
  • e2label /dev/sdXXX2 el7
  • sync
  • cd /; umount /mnt/tmp
  • eject /dev/sdXXX
  • try to boot, should boot all the way to the login prompt.

Create bootable Raspbian SD card

Two ways:

  • download and "dd" the Raspbian OS image (then customize it per Raspbian and Ubuntu instructions)
  • clone an already customized Raspbian image

To clone a customized image:

  • use a 32 GB micro-SD flash card
  • make it bootable (see instructions above, select cmdlinux-mmcblk.txt)
  • add the Raspbian userland (follow CentOS-7 instructions above, but rsync Raspbian image instead of CentOS-7 image)

Network-boot Raspbian

Prepare the boot server in the usual way:

  • setup dhcpd or dnsmasq to serve the IP address and the NFS-Root mount path for the userland image
  • tftp is not used, is not needed
  • setup NFS server to permit mounting the userland image. in /etc/exports have this:
/zssd1tb/nfsroot @xxx_netgroup(rw,no_root_squash,async)
  • do not forget to enable dhcpd/dmsmasq and NFS to start on boot
  • do not forget to run "exportfs -rv" and "systemctl restart dhcpd" after making any changes

Prepare a bootable SD card

  • use SD card of any size (8 GB or bigger)
  • follow instructions to make it bootable
  • select cmdline-nfsroot.txt
console=serial0,115200 console=tty1 ip=dhcp rw root=/dev/nfs panic=60

Install bootable SD card into RPi, power up, and observe:

  • RPi boots linux kernel
  • linux kernel starts
  • makes DHCP request, receives answer
  • RPi pings
  • RPi mounts the NFS-Root filesystem as specified by DHCP
  • RPi OS boots normally
  • there is a login prompt
  • from boot server, RPi pings and ssh'es.

Setup Python i2c tools

NOTE: DO NOT DO THIS!

su - root
yum install python-setuptools.noarch
yum install python-cffi
yum install python-devel
cd git
git clone https://github.com/bivab/smbus-cffi.git
cd smbus-cffi
python setup.py install

Enable i2c drivers

NOTE: DO NOT DO THIS!

(already done) edit boot config.txt, uncomment "dtparam=i2c_arm=on" and "dtparam=i2c1=on", reboot
echo modprobe i2c-dev >> /etc/rc.local
echo modprobe i2c_bcm2708 >> /etc/rc.local
ls -l /dev/i2c*
i2cdetect -l
i2cdetect 1
echo chmod a+wr /dev/i2c* >> /etc/rc.local
reboot, run i2cdetect again.

Script for creating boot files

~olchansk/git/scripts/clone/boot_rpi3.perl

Boot modes

See https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/msd.md and https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/bootflow_2711.md

  • RPi2, RPi3B - SD flash is the default. USB mass storage boot is disabled, but can be enabled.
  • RPi3B+ - default boot order: SD flash, USB boot
  • RPi4B - boots from internal SPI EEPROM (see recovery.bin). continues booting from SD flash. network boot (DHCP+TFTP), firmware 2020-xx-yy. (how to enable?). usb mass storage boot (not available as of 2020-apr-21).

Raspbian OS

Recommended RaspberryPi OS is "Raspbian".

Rapsbian images and kernel versions

  • 2016-09-23-raspbian-jessie-lite : Linux version 4.4.21+
  • 2020-05-27-raspios-buster-lite-armhf : Linux version 4.19.118-v8+
  • 2021-01-11-raspios-buster-armhf-lite : ???
  • 2021-03-04-raspios-buster-armhf-lite : Linux version 5.10.17-v7+

Raspbian boot from SD card

  • download here https://www.raspberrypi.org/downloads/raspbian/
  • unzip, dd to a 32GB SD flash card
  • insert card into RPi3, power up, it will boot into login prompt
  • default user: pi, password: raspbian, login change default password, install ssh keys for user pi and user root.
  • change default keyboard layout from UK (with the pound key): vi /etc/default/keyboard, set XKBLAYOUT="us"
  • change default locale from UK to "C" (en_US.UTF8 does not seem to be available): vi /etc/default/locale, set LANG=C.UTF-8
  • enable ssh server: apt-get install openssh-server, systemctl enable sshd.service, systemctl start sshd.service
  • reboot: shutdown -r now
  • RJ45 ethernet network will autoconfigure by DHCP, ssh pi@... and root@... should work
  • login as root, install missing packages:
    • apt-get update
    • apt-get install git emacs xemacs21 cmake
  • install additional packages as needed as listed here: https://daq.triumf.ca/DaqWiki/index.php/Raspbian and here: https://daq.triumf.ca/DaqWiki/index.php/Ubuntu

Backport python3-yaml to Debian Buster

Debian Bullseye ships pyYAML 5.3.1, it is relatively easy to build the package for Debian Buster.

1. Downlowd

http://deb.debian.org/debian/pool/main/p/pyyaml/pyyaml_5.3.1.orig.tar.gz

and

http://deb.debian.org/debian/pool/main/p/pyyaml/pyyaml_5.3.1-1.debian.tar.xz

from https://packages.debian.org/bullseye/python3-yaml (under "Download Source Package"). Note the bullseye in the URL.

2. Unpack pyyaml_5.3.1.orig.tar.gz and, inside the PyYAML-5.3.1 directory, pyyaml_5.3.1-1.debian.tar.xz.

3. Install some dependencies needed for the build:

sudo apt install python3-all-dev python3-all-dbg libyaml-dev cython cython-dbg python-all-dev python-all-dbg
sudo apt install dpkg-dev

4. Build the package (on the target architecture)

sudo dpkg-buildpackage -us -uc -nc

Openbox X Session

Have a look in /etc/xdg/openbox


Custom Raspbian Images

The official tool used raspberrypi.org is available here: https://github.com/RPi-Distro/pi-gen

It is working out of the box with Debian bullseye. The tool is built around debootstrap, all packages are pulled from http://archive.raspbian.org/ (not the official debian repos!).

The user has to provide a config file named "config" in the root directory. For instance:

IMG_NAME=MVM_GUI_TRIUMF 
RELEASE=buster
DEPLOY_ZIP=0
USE_QEMU=0
LOCALE_DEFAULT=C.UTF-8
TARGET_HOSTNAME=mvm_gui
KEYBOARD_KEYMAP=us
KEYBOARD_LAYOUT="English (US)"
TIMEZONE_DEFAULT="America/Vancouver"
FIRST_USER_NAME="mvm" 
FIRST_USER_PASS="gui"
ENABLE_SSH=0
STAGE_LIST="stage0 stage1 stage2 stage3 stage4"

To build the image, simply run ./build.sh and wait.

MVM example

Let's build an image tailored to the MVM GUI. The assumes the user is running Debian bullseye.

Optional Step: Setup a Local APT Cache

A local cache speeds-up things if you have to (re)build multiple images. The procedure supposes that you have docker and docker-compose installed on the build machine.

In the root directory, run

apt install docker-compose ### Ubuntu LTS 18.04
docker-compose up -d 

Add the line

APT_PROXY=http://172.17.0.1:3142 

to the config file

Main Procedure

Install dependencies (Debian):

sudo apt install coreutils quilt parted qemu-user-static debootstrap zerofree zip \
dosfstools bsdtar libcap2-bin grep rsync xz-utils file git curl bc

Install dependancies (Ubuntu LTS 18.04)

ssh root@...
apt-get install quilt qemu-user-static debootstrap zerofree bsdtar curl

Clone the TRIUMF repo:

https://gitlab.triumf.ca/mvmdev/GUIAutoBuild --single-branch slim-raspbian-buster

Run:

LANG=C.UTF-8 ./build.sh

Wait ... the images will be saved in the deploy directory.

GPIO

  • apt-get install wiringpi
  • gpio readall
  • gpio mode 24 output
  • gpio write 24 1
  • gpio write 24 0

SPI

  • if there is no /dev/spidev0.0 and /dev/spidev0.1, edit /boot/config.txt, uncomment dtparam=spi=on, reboot
  • CS pins are:
    • CE0 is J8 pin 24 (GPIO8) is /dev/spidev0,0
    • CE1 is J8 pin 26 (GPIO7) is /dev/spidev0,1

I2C

  • if there is no /dev/i2c*:
    • mount /dev/mmcblk0p1 /boot
    • edit /boot/config.txt, uncomment "dtparam=i2c_arm=on"
    • run "echo i2c_dev >> /etc/modules-load.d/i2c_dev.conf"
    • umount /boot
    • reboot
    • after reboot check that i2c_dev and i2c_bcm2835 modules are loaded:
root@lvdb04:~# lsmod | grep i2c
i2c_dev                20480  0
i2c_bcm2835            16384  0
root@lvdb04:~# 
  • if no permission to open /dev/i2c*:
    • edit /etc/group, add your user to group "i2c", for example:
root@lvdb04:~# grep i2c /etc/group
i2c:x:998:pi,agdaq
root@lvdb04:~# 
    • logout, login again (/etc/group is applied at login time)
  • apt-get install python-smbus i2c-tools
  • i2cdetect -y 1 ### found device at address 0x70:
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- -- 
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 
70: 70 -- -- -- -- -- -- --                         

WiFi and Bluetooth

The WiFi and Bluetooth interfaces can be disabled in the boot/config.txt. As a side effect, the PL011 UART is re-routed to the GPIOs 14 and 15. By default, the UART is used by the BT modem.

One has to disable the BT modem initialization service to avoid conflicts.

systemctl disable hciuart

Note: there is a second "MiniUART" aviabale on the Rpi, but its fonctionally are very limited. See https://www.raspberrypi.org/documentation/configuration/uart.md

# Disables the Bluetooth device (also restores UART0/ttyAMA0 to GPIOs 14 and 15).
dtoverlay=disable-bt
dtoverlay=disable-wifi

RS232

The Rpi3 has two serial interfaces (https://www.raspberrypi.org/documentation/configuration/uart.md). Levels are *3.3V*.

Rpi3 RS233 3.3V wiring with a standard TTL-232R to USB serial cable (FTDI chip)

Update RPi firmware

!!! check that SD card is mounted as /boot/firmware !!!

apt update
apt upgrade ### install latest eeprom
rpi-eeprom-update -a

RPi4 boot from network

  • run raspi-config, in advanced options, set boot order to network-first
  • reboot
  • check that the change took
root@magpi03:~# vcgencmd bootloader_config
[all]
BOOT_UART=0
WAKE_ON_GPIO=1
POWER_OFF_ON_HALT=0

[all]
BOOT_ORDER=0xf21
  • shutdown, power off the RPi4
  • remove SD card
  • power up
  • tail -100f /var/log/syslog
  • observe RPi4 does DHCP and requests files from /tftpboot/SERIALNUMBER/
  • give it files it want, copy the from the SD card /boot/firmware
  • copy all of /boot/firmware/overlays to /tftpboot/...
  • symlink kernel8.img and initramfs8 to files in /nfsroot/
  • should have this:
root@haicudaq01:~# ls -l /tftpboot/c914e0e6/
total 1732
-rwxr-xr-x 1 root root   56112 Nov 26 15:43 bcm2711-rpi-4-b.dtb
-rwxr-xr-x 1 root root      70 Nov 26 15:43 cmdline.txt
-rwxr-xr-x 1 root root    1245 Nov 26 15:40 config.txt
-rwxr-xr-x 1 root root    5456 Nov 26 15:42 fixup4.dat
lrwxrwxrwx 1 root root      27 Nov 26 15:47 initramfs8 -> /nfsroot/magpi03/initrd.img
lrwxrwxrwx 1 root root      24 Nov 26 15:47 kernel8.img -> /nfsroot/magpi03/vmlinuz
drwxr-xr-x 2 root root     339 Oct 22 06:05 overlays
-rwxr-xr-x 1 root root 2259296 Nov 26 15:37 start4.elf
root@haicudaq01:~# 
  • cycle power on the RPi4, it should boot from the network (SD card removed)
  • not so fast. it did not boot all the way, ssh does not work.
  • go to /nfsroot/magpi03/etc/fstab, edit /boot/firmware to have "nofail" otherwise boot will stall at mounting the removed SD card:
/dev/mmcblk0p1  /boot/firmware  vfat    defaults,nofail          0       2
  • cycle power on RPi4 again, now it should boot all the way to ssh
  • ssh magpi03
  • disable swap (swap to NFS does not/cannot work)
systemctl stop dphys-swapfile
systemctl disable dphys-swapfile
rm /var/swap
  • done

End