Berkeley Pi: Next meeting on Jitsi Sunday the 21st

[tom r lopes]

meet.jit.si/berkeleypi 

Sunday June 21 2020 from 11am to ? 

Pi news:  

Pi foundation announced the 8GB version of the Pi 4 https://www.raspberrypi.org/blog/8gb-raspberry-pi-4-on-sale-now-at-75/

So this means now we need a 64bit OS.  Recall that Raspbian is 32bit only.  I hadn't realized myself but Raspbian isn't actually 

put out by the Pi foundation.  It is actually a 3rd party.  https://www.raspbian.org/FrontPage

So the foundation is creating their own called Raspberry Pi OS https://www.raspberrypi.org/forums/viewtopic.php?f=117&t=275370

which has a 64bit image (in beta).  

Newer Linux kernels have much better support for Arm cpu so there is not as much need for a heavily modified distro.  

Ubuntu has official 20.04 server for the Pi https://ubuntu.com/download/raspberry-pi You could probably install Ubuntu 

server then sudo apt install whichever desktop you like.  (I haven't tried myself, yet)

Pi foundation announced USB boot firmware for the Pi 4.  (beta, again)  Previously USB boot was only for 

Raspberry Pi 3B, 3B+, 3A+ or a Raspberry Pi 2B v1.2. You can find the documentation here: 

https://www.raspberrypi.org/documentation/hardware/raspberrypi/bcm2711_bootloader_config.md

(Scroll down the page to see USB)  Note that it is for USB mass storage device.  If it is detected to be 

USB Attached SCSI  This is another thing I have to try out!

New official Pi hardware:  New camera module that they are calling HQ (for High Quality)  

It has an 12.3mp sensor and standard screw for tripod mount.  It doesn't come with a lens.  

For that you will have to provide your own.  It takes C-mount lens and also comes with CS-mount adapter.  

Now, I don't know much about photography and cameras, so I may be wrong in what I say.  

So I understand that C and CS are common for Closed Circuit cameras (CCD) they both use the same thread (1 in dia.) 

but the CS holds the lens farther from the sensor.  https://www.raspberrypi.org/blog/new-product-raspberry-pi-high-quality-camera-on-sale-now-at-50/

I've ordered one of these and should have it by the meeting, but I forgot about the lens though.  Just ordered the 

official telephoto lens and hopefully it makes it by Sunday.  But I have a couple that I got off Ebay and one I found on the sidewalk.  

https://photos.app.goo.gl/AYSJ2RizU4UXC8os6  The black ones are from Ebay both C-mount.  Both have control cabling.  

Small one has a cut cable and looks like 4 conductors.  Large one has an 8 pin DIN.  

Silver one I found walking around. The thread is 1 1/4 in but I found that the inside thread accommodates the C/CS.  So 

maybe an adapter is possible.  The lens says "Sony TV Zoom" But it doesn't appear to be a Sony standard thread mount 

(or of any other standard that I can find)  https://en.wikipedia.org/wiki/Lens_mount

Thomas

[Rick Moen]

Quoting tom r lopes (tomr...@gmail.com):

> Pi foundation announced the 8GB version of the Pi 4
> https://www.raspberrypi.org/blog/8gb-raspberry-pi-4-on-sale-now-at-75/
> So this means now we need a 64bit OS.

In case people are wondering _why_: 32-bit OSes cannot efficiently
address and use more than 4GB of RAM address space. So, if running a
32-bit distro like Raspbian on a 8GB or (future) 16GB RPi 4, quite a bit
of the RAM you bought would end up badly used, partially wasted.

The ARM Cortex-A72 CPU used in the RPi 4 series supports both a 64-bit
mode (called 'aarch64') and a 32-bit mode (called 'aarch32').[1]
Technically, these are two execution modes (think of them as
personalities) of the ARMv8 architecture's latest implementation (called
the ARMv8-A spec).

So, long story short, a Linux distro compiled for the aarch32 CPU
architecture (as is Raspbian) will work fine on any RPi 4, but will suck
at making proper use of any system RAM in excess of 4GB. OTOH, a Linux
distro compiled for the aarch64 CPU architecture will run even better on
RPi 4 in the sense of doing better at handling 8GB (and in the future
higher) machines.

Doing a search at Distrowatch
(https://distrowatch.com/search.php?ostype=All&category=All&origin=All&basedon=All&notbasedon=None&desktop=All&architecture=aarch64&package=All&rolling=All&isosize=All&netinstall=All&language=All&defaultinit=All&status=Active#simple)
suggests these open source *ix options (including BSD in addition to
Linux):

Manjaro Linux
Debian GNU/Linux
Fedora
KDE neon
CentOS
openSUSE
Ubuntu Kylin
FreeBSD
Q4OS
Alpine Linux
Ubuntu MATE
Void Linux
Mageia
Red Hat Enterprise Linux
Netrunner
ALT Linux
Raspberry Pi OS (in beta, which Thomas described)
Oracle Linux
Funtoo Linux
Bedrock Linux
Fugulta
Proton OS

aarch64 distros that Distrowatch hasn't yet caught up with, sucn as
Ubuntu Server 20.04 LTS and 18.04, and also Arch Linux ARM, Gentoo,
Blackarch, BalenaOS, EasyOS, and Linaro, are not yet included in
Distrowatch search results (but should be).

[1] The Linux kernel developers and Debian have so far chosen to refer
to aarch64 by the name 'ARM64'. Everyone else, to my knowledge, as
followed the lead of the GCC developers, who invented the name
'aarch54': Doing cross-compilation for aarch64 Linux in GCC requires
specifying target architecture 'aarch64-linux-gnu-gcc'.