Topics

RPi (Raspbian) on LAN

Gordon Haverland
 

Well, I got tired of waiting for some adapter to show up, so I got a
HDMI/DVI cable and the Raspberry Pi 3B+ booted up just fine. Set the
keyboard, location and timezone stuff, it wants to do updates, and then
it is ready.

I suspect all RPi running Rasbian get the same hostname (raspberrypi).
I am going to guess that Raspbian is one of these Linuxen which does
the sudo crap.

Is there a list of things a person should do, when adding RPi to a LAN,
so that they are all "unique"? I guess if you want to be able to SSH
to the RPi, you need to create some file. If all you do is touch the
file, it seems that on the next boot, it starts a ssh server and then
deletes this file. Can you just set it imutable so that you always get
ssh?

Thanks.

--

Gord

Gordon Haverland
 

On Wed, 8 Jan 2020 12:31:46 -0700
"Gordon Haverland" <ghaverla@...> wrote:

Well
Running raspi-config I can change some of the stuff I want to change.
Something that is here, is Lennart (systemd). TheRegister had a blurb
a day or so ago. There are 28M lines of code in the Linux kernel.
Systemd has more than 1M lines of code.

Raspbian seems to be Debian based. I believe Armbian is Debian based
as well. I suspect both default to systemd. Bleech!


Little computers (like routers) seem to suffer from entropy
production. And it was nice to see
apt-get install haveged
work. There are other things a person can do to feed entropy, but
haveged is one that I have grown used to.

The Raspberry Pi I bought is a 3B+, and it came with a case and a
touchscreen (3.5 inch). A blurb on the raspberry pi website, was about
installing touchscreen support. And it started with installing things
that shouldn't have anything to do with the package, changing IP
addesses and sorry, there has to be a better way.

It may be that support for the touchscreen is already here, if nothing
else when I plug in power (even before having the HDMI to DVI-D cable),
the touchscreen came up white. Which apparently what the support is
supposed to do.

I though dmesg might show me something. It may have shown me
something, but I don't know enough to recognize what it is. So, I am
going to install some hw tools to see if it can glean what this touch
screen is.

A small touchscreen with no keyboard is going to be vastly different
anything else. But I am wondering just why I was able to find a "kit"
with a touchscreen, and no instructions.


We had a slight amount of snow, and so I had my tractor with no cab
plugged in for 5 hours, and it was a little sluggish to start. I let
it warm up a lot, hydraulics on the loader were slow.

I recently tried making a home-made version of vanilla cream for
coffee. FORTRAN-vanilla? Nope, sorry. French-Vanilla. The stock
recipe I found (almond milk, coconut milk) did NOT impress my Mom. She
want's the addition of "cream" to "whiten" the coffee.

Some people advocate for adding gelatin to "thicken" these home made
creams. Other sites advocate using flours (like tapioca). The basic
problem, is that you need to heat the "cream" to near boiling. Which
is going to alter the taste profile. Maybe you prefer the altered
profile, but shouldn't you be able to find the unaltered profile some
how?

Some particles look like dots, some look like lines and some look like
circles. Clay particle tend to look like circles, and so they have a
large surface area for a small volume. Which means they thicken
liquids they interact with, quite significantly.

If you find your self a rotary cheese grater based on a microplane, and
you grind yourself some "flakes" of nuts and add them to the almond
milk/coconut milk mixture that is too thin, you will find that it
thickens the mixture. I've gone through 2 iterations with ading
macadamia nut flakes to almond milk/coconut milk; and this last
iteration was a big improvement. It probably isn't the answer you were
looking for.

But, if you are making almond milk from scratch and adding coconut
milk/cream; then continuing to added grated almond will eventually get
you to a viscosity which approximates adding commercial creamer to
coffee.

Joan Leach
 

I remember reading a DYI article in Instructables.com newsletter where he made his own portable Raspberry with a touchscreen. On Distrowatch.com, I think they link to Raspberry mags and Distros, etc.

Joan in Reno

On Wednesday, January 8, 2020, 04:53:21 PM PST, Gordon Haverland <ghaverla@...> wrote:


On Wed, 8 Jan 2020 12:31:46 -0700
"Gordon Haverland" <ghaverla@...> wrote:

> Well

Running raspi-config I can change some of the stuff I want to change.
Something that is here, is Lennart (systemd).  TheRegister had a blurb
a day or so ago.  There are 28M lines of code in the Linux kernel.
Systemd has more than 1M lines of code.

Raspbian seems to be Debian based.  I believe Armbian is Debian based
as well.  I suspect both default to systemd.  Bleech!


Little computers (like routers) seem to suffer from entropy
production.  And it was nice to see
apt-get install haveged
work.  There are other things a person can do to feed entropy, but
haveged is one that I have grown used to.

The Raspberry Pi I bought is a 3B+, and it came with a case and a
touchscreen (3.5 inch).  A blurb on the raspberry pi website, was about
installing touchscreen support.  And it started with installing things
that shouldn't have anything to do with the package, changing IP
addesses and sorry, there has to be a better way.

It may be that support for the touchscreen is already here, if nothing
else when I plug in power (even before having the HDMI to DVI-D cable),
the touchscreen came up white.  Which apparently what the support is
supposed to do.

I though dmesg might show me something.  It may have shown me
something, but I don't know enough to recognize what it is.  So, I am
going to install some hw tools to see if it can glean what this touch
screen is.

A small touchscreen with no keyboard is going to be vastly different
anything else.  But I am wondering just why I was able to find a "kit"
with a touchscreen, and no instructions.


We had a slight amount of snow, and so I had my tractor with no cab
plugged in for 5 hours, and it was a little sluggish to start.  I let
it warm up a lot, hydraulics on the loader were slow.

I recently tried making a home-made version of vanilla cream for
coffee.  FORTRAN-vanilla?  Nope, sorry.  French-Vanilla.  The stock
recipe I found (almond milk, coconut milk) did NOT impress my Mom.  She
want's the addition of "cream" to "whiten" the coffee.

Some people advocate for adding gelatin to "thicken" these home made
creams.  Other sites advocate using flours (like tapioca).  The basic
problem, is that you need to heat the "cream" to near boiling.  Which
is going to alter the taste profile.  Maybe you prefer the altered
profile, but shouldn't you be able to find the unaltered profile some
how?

Some particles look like dots, some look like lines and some look like
circles.  Clay particle tend to look like circles, and so they have a
large surface area for a small volume.  Which means they thicken
liquids they interact with, quite significantly.

If you find your self a rotary cheese grater based on a microplane, and
you grind yourself some "flakes" of nuts and add them to the almond
milk/coconut milk mixture that is too thin, you will find that it
thickens the mixture.  I've gone through 2 iterations with ading
macadamia nut flakes to almond milk/coconut milk; and this last
iteration was a big improvement.  It probably isn't the answer you were
looking for.

But, if you are making almond milk from scratch and adding coconut
milk/cream; then continuing to added grated almond will eventually get
you to a viscosity which approximates adding commercial creamer to
coffee.




Gordon Haverland
 

Incomplete documentation makes life interesting.

I guess I need to find out what particular model I have. So, I will
work at that.

I connected the RPi to a monitor and keyboard for this setup. The
monitor is a fairly big Benq. Unlike the 3 Devuan machines around it,
the RPi never does put the monitor into a proper sleep mode. So
although the display was "black", quite a lot of light leaks out at
night.

--

Gord

Gordon Haverland
 

On Thu, 9 Jan 2020 09:45:49 -0700
"Gordon Haverland" <ghaverla@...> wrote:

I guess I need to find out what particular model I have. So, I will
work at that.
The preferred way for someone to find out something about this
hardware, is apparently to scan a QR code. Wonderful. I did find the
description XPT2046.

It seems that there are many different resistive touchscreens of a
similar nature. That in of itself is not an indication of anything
bad. There are a bunch of 120 VAC temperature controllers that all
seem to work well, of a similar nature.

Stack exchange has a page on this:

https://raspberrypi.stackexchange.com/questions/78334/what-have-you-done-to-make-generic-tft-touchscreen-display-work

On that page, they explicitly point to this URL

https://github.com/goodtft/LCD-show

This particular github site seems to be forked a number of times. This
site has the last commit being Nov 7, 2019 (fairly recent). The other
git sites I looked at, seemed to be older.

So, I am guessing this is probably one of the better variants to use.
There are instructions for Ubuntu, Kali, Retropie and Raspbian.

This repository no longer calls these monitors by part numbers that
look like XPT2046. The 3.5 inch one is called one of: MPI3501, MPI3508
(HDMI), MHS3528 or MHS35xx (X not 28?).

There is a link to an English wiki page, which states that the touch
screen controller is an XPT2046.

A few sites talking about this hardware, mention a package called
xinput-calibrator that is in the Raspbian system. I suspect the
version numbers all these comments use, is the first one to work? So
you want this, or newer?

If you clone the github site onto your RPi, there are a bunch of
programs which are part of this. Presumably they are all the result of
a compile. And presumably a person should read the source code, save
the binaries to some other place, re-run make (or whatever) to remake
the binaries to see that the binaries haven't been replaced with
something nasty.

--

Gord