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Raspberry Pi
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Jul 11 00:48 UTC 2015 |
The Raspberry Pi is a range of very small, very
affordable microcomputers that can be used with a keyboard,
mouse and screen and have input/output pins that can be used
to monitor or control other circuitry or devices.
This is an item where we can share our experiences with
the Raspberry Pi (and similar computers) and ask questions.
If you have one, what version is it and what do you use it
for?
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| 47 responses total. |
kentn
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response 1 of 47:
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Jul 11 22:13 UTC 2015 |
I've got a Beaglebone Black, which is similar to the Pi. The Pi has
better video output, though. These little computers are about the size
of a pack of cigarettes. One of the problems I have with it is keeping
it on the table. It's easy to tug on a cable and pull it on the floor.
You can, in theory, screw them onto the back of a monitor that has the
appropriate connections.
A number of different operating systems run on these computers,
including the distribution of Linux that came preinstalled (the
Beaglebone uses Debian, the Pi uses Raspbian), Risc OS, Plan 9, other
Linux distributions, and Android, so you have lots of choices. Probably
someone is getting another OS running on a Pi right now.
There are accessories for these little computers, as you might expect,
such as expansion boards you can connect that provide additional
functionality. Beaglebone calls them "capes." If you don't have an
ethernet port or wi-fi, a card can add that functionality, for example.
You could, if you were motivated, use a Raspberry Pi as a desktop
computer. It isn't the fastest, but it will do the job and it's not
very expensive. With free office application software like Open Office
or LibreOffice you can do spreadsheets, word-processing, etc.
I'd like to use mine for monitoring my weather station. Right now
I'm using an old laptop running Windows for that, but it draws a lot
more electricity than this little single card computer. For something
runs constantly like that, having a low power computer do the work
would save some money.
They are definitely lots of fun and use for not much money.
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keesan
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response 2 of 47:
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Jul 12 03:20 UTC 2015 |
Are there weather apps for cell phones?
There is a "Squeezed Arm" puppy linux for the Pi. Puppy SAP. Alpha.
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ball
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response 3 of 47:
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Jul 12 15:26 UTC 2015 |
A cellphone might work if the weather station offered a
BlueTooth interface and if you were comfortable programming
a cellphone. I suspect that the input/output pins on boards
like the Raspberry Pi and BeagleBone would make those more
convenient.
I have a Raspberry Pi model B. I've used it
experimentally as a graphical terminal and to run network
tests. One drawback is that the wired Ethernet port is a bit
slow. I look forward to trying the Raspberry Pi 2 model B at
some point. It has a faster processor and faster Ethernet.
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kentn
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response 4 of 47:
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Jul 12 15:32 UTC 2015 |
Yes, there are weather apps for cell phones. Weather Underground is one
such. However, I'm sending data from my weather station, not checking
the weather. It is something that runs 24/7, else you get e-mails from
wunderground saying your station hasn't reported for X hours. After a
while of not reporting or reporting bad readings, they drop you from
their system and you need to get all set up again (or argue why you
should be allowed to connect). I'd rather not do that. I can't do
anything about power outages of 4 hours, the cable company drops it
connection, if the computer crashes, or similar. But I try to keep
the station reporting as much as possible. So far, those are the only
things that have knocked it off line for a few hours. This is not a
frequent occurrence.
There are a couple porgrams for Unix to allow weather stations to send
data. One is weewx. They can be made to work on a Pi or Beaglebone or
similar credit-card computer.
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kentn
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response 5 of 47:
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Jul 12 16:22 UTC 2015 |
BTW, my weather station is wireless (wi-fi) and connects to a small
base station LCD readout, which then connects via USB to an old laptop
I have. But, to try to wire it into a Pi directly would be more pain
that I want to endure (and more wires than I want to run from the back
yard to the front of the house). But, it probably could be connected
directly if you wanted to fiddle with things for fun. The Beaglebone
Black has an ethernet port for network connection and a USB port where
you can connect a USB hub if you want. I have a wireless Logitech
mouse/keyboard USB dongle connected there right now. That works as
expected.
Let us know how the Pi 2 works. Sounds interesting.
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ball
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response 6 of 47:
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Jul 12 16:43 UTC 2015 |
I've used a USB hub with my Raspberry Pi model B, so
that I could have keyboard, mouse and a 16G USB flash drive
plugged in at the same time. It boots NetBSD from an SD card
and I use the USB flash drive for pkgsrc.
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kentn
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response 7 of 47:
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Jul 12 20:12 UTC 2015 |
I've seen on the weewx googlgroup that some people are using
a Raspberry Pi to collect the data from their weatherstation,
so it's possible. I figured it was.
Yes, these little computers definitely need some sort of
keyboard, mouse and monitor if you want to sit on the console
and use them. You can also connect to them from other computers,
so can do work that way. Pretty neat, all the way around.
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kentn
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response 8 of 47:
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Jul 14 22:25 UTC 2015 |
That new Raspberry Pi (the Pi 2) looks pretty neat. Quad-core CPU, 1
gig of RAM. Should be quite speedy and useful and still very small (same
size as the rest of the Raspberry Pi models).
What I've been reading and researching lately is using a Raspberry Pi to
extend an Apple 2 computer. You can use the Pi to handle the network
connections and web browsing (and email, IRC, etc.) and still view the
results on an Apple 2. Or not. Some people have been able to attach a
modern monitor to the Pi and do work on both the Pi and the Apple 2 at
the same time. Kind of neat. That's one way to make an old computer
useful and a lot cheaper than buying an ethernet card for the Apple 2.
I've seen two ways to do it. One is to use a null serial cable to
connect the Pi to the Apple 2 with a Super Serial card. Then use a
terminal program (e.g. ProTerm or Kermit) on the Apple 2 to connect to
the Pi and watch applications run on the Pi via the terminal program.
The other is to connect the Pi to a special Apple 2 interface card. The
card integrates the Pi output with the Apple 2's output and you can
switch back and forth between the two computers.
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kentn
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response 9 of 47:
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Jul 25 20:28 UTC 2015 |
Somewhere along the line in one of these items someone mentioned RDP
(remote desktop protocol) connections, and somewhere I read that
Raspberry Pi (and Beaglebone Black) can connect that way. So I tried
it. It worked! You end up on a desktop and can start applications
such as xterms or other terminals, along with other things like file
browsers and web browsers, etc.
I ended up installing xrdp on my FreeBSD box so I could connect to a
remote desktop there, too. Quite nice. Now, when my desktop computer
hibernates, or installs a Windows update and reboots, I don't lose my
xterms. I just restart the remote desktop and there they are running
happily on the unix server, be that a Raspberry Pi, a Beaglebone
Black or my FreeBSD server. So, another neat feature of these little
credit-card sized computers, due to the OS setup they are running.
This also means you can use the monitor on a desktop computer to work on
your Pi or Beagle without hooking up a monitor directly.
If I remember correctly, the Beagle uses LXDE as its window manager.
I've got xfce4 running on my FreeBSD box and that works, okay, too.
LXDE can also be installed on FreeBSD quite easily. I'm not sure what
the Raspberry Pi uses.
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kentn
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response 10 of 47:
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Jul 29 12:00 UTC 2015 |
Since this new Raspberry Pi 2 with the quad-core processor looks so
neat, I thought I'd look into getting one. I've usually ordered from
Adafruit for most things, and they've done great. I looked on Amazon,
however, and although a number of suppliers are almost 5 star rated,
there are some disconcerting 1-star ratings in there where people got
a totally different Pi model. I know sometimes competitors do things
like that, so it's hard to tell about the reliability. And, we're not
talking a significant number, either. A supplier wouldn't get almost-5
if they had lots of 1's and 2's.
So, my questions would be: when you've bought your credit-card computer,
which source/supplier did you use? What experiences did you have in
buying?
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ball
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response 11 of 47:
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Aug 2 02:07 UTC 2015 |
This response has been erased.
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kentn
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response 12 of 47:
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Aug 2 18:13 UTC 2015 |
Sounds, good, Andy. I've bought several things from Adafruit
and been happy with the experience. As you say they provide
lots of information on how to use/set up what you get and
that really helps for parts that are not largely plug and
play.
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kentn
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response 13 of 47:
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Oct 14 12:52 UTC 2015 |
Adafruit came through in excellent fashion for me again. I ordered a
Raspberry Pi 2B with case and power supply. All arrived in 3 business
days. Now I just need to get Raspbian on a microSD card and see if it
will boot. That's one thing I liked about the Beaglebone Black: it
booted right out of the box into a Debian-ish OS. But, this Raspberry
Pi 2 is quite a bit more powerful than the Beaglebone Black. They are
essentially the same size. I'm looking forward to having more RAM and
a quad-core processor. That should help some applications, like web
browsers, run more smoothly.
Once again, I was happy with Adafruit's information about how to install
the RPi 2 in the case. It snaps in with quite a bit of force. Part of
the trick was to get the connectors on the HDMI side of the board into
the cutouts on the side of the case and line the board up evenly. Then
they told how to push one side and then the other into the clips in the
case. The main thing was they said don't worry, it takes a lot of force
to break the clips. Of course, if you don't have it lined up right, the
board sits on top of the clips and won't push down. Having the pictures
on the Adafruit site helped a lot. This was one of the Adafruit plastic
cases (the snap on lid is separate).
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kentn
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response 14 of 47:
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Oct 18 03:38 UTC 2015 |
Okay, I got raspbian jesse installed on a microSD and that worked to
get my Raspberry Pi 2 B working. Now I'm setting it up. I don't
have a keyboard or mouse or monitor on it right now, but of course
I can connect to it with ssh and work on it. Next up will be hooking
a monitor to it.
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ball
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response 15 of 47:
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Oct 20 01:50 UTC 2015 |
I used an HDMI to DVI-D cable with my Raspberry Pi model
B. I daresay an ordinary HDMI cable would work too if your
monitor has a suitable input for that.
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kentn
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response 16 of 47:
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Oct 20 02:19 UTC 2015 |
Yup, it will. I got it pretty much set up (a few more packages to
install). It is accessible from my FreeBSD box just fine via xterm,
and also via xrdp and a remote desktop connection from Windows. What I
was playing with today was the wolfram command line. The Mathematica
app wouldn't start (well, it loaded its kernel and as it came to its
opening screen, it took my whole remote desktop connection down). So,
something needs to be configured. I had to do the "add the user to the
video group" thing to get to the wolfram command line, so maybe there is
something else I need to do to get the Mathematica app running.
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ball
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response 17 of 47:
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Oct 20 12:30 UTC 2015 |
I tend to use VNC for headless work (including my main
PC, which currently runs NetBSD/i386 6.1.5). When I had my
Raspberry Pi set up at work though, I had it plugged into a
monitor.
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kentn
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response 18 of 47:
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Oct 21 03:09 UTC 2015 |
I might try VNC. It sounds fairly decent. Also plugging it into
a monitor. It's on the LAN via an Ethernet cable. The plastic
case I got is working out okay. It's not very heavy, of course,
but protects the board and still allows access to the ports,
the microSD card slot and other connections on the pi. It seems
reasonably speedy, as it should.
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kentn
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response 19 of 47:
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Oct 21 19:26 UTC 2015 |
Okay, I've got TightVNC installed and can access the Pi from
Windows now. I'll see how it goes. I still like Xrdb okay.
Part of the fun with VNC was knowing which port it was running
on, but checking running processes showed that fairly quickly.
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kentn
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response 20 of 47:
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Oct 22 00:49 UTC 2015 |
BTW, Mathematica is a lot fun, especially playing around with graphs
and symbolic math. On Grex, about the closest we can come to this is
GNU Octave, which is installed. Another we have installed is Freemat.
Anyway, for less than $100 in computer hardware, to be able to run
Mathematica (for personal used) is quite amazing, and even more so since
it is free with the Raspberry Pi.
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kentn
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response 21 of 47:
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Oct 27 01:03 UTC 2015 |
Maxima is now installed on Grex, and it is closer to Mathematica in some
ways, although Octave can do an awful lot, too.
TightVNC works well for running Mathematica in GUI mode. So I've been
using VNC for that.
Xrdp, to me, still provides a better desktop, but perhasp VNC can be
configured to provide a similar size of desktop.
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ball
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response 22 of 47:
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Oct 28 00:06 UTC 2015 |
VNC can provide arbitrary desktop sizes and works better
over a WAN pipe than X11. Not sure about RDP.
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kentn
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response 23 of 47:
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Oct 28 03:26 UTC 2015 |
I've got it more or less using most of the screen now. Took
a little messing around to get it. I'm not sure about the
quality of the image though. Terminals, for example, are
rather hard to read.
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kentn
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response 24 of 47:
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Oct 31 20:06 UTC 2015 |
Okay, the quality of the image was due to whatever magnification
was being applied. When I set it 100%, it started looking sharp
and crisp like it should. Terminal text was a bit fuzzy before
that. I'm quite liking this little computer in terms of the speed
and the remote desktop capability. It's mainly a neat thing to
play with right now, but it's not difficult to see that it could
be used for serious work if a person couldn't afford a more
powerful computer. And the size means it can fit in a lot of
places where a desktop computer wouldn't fit.
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