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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?
47 responses total.
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.
Are there weather apps for cell phones? There is a "Squeezed Arm" puppy linux for the Pi. Puppy SAP. Alpha.
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.
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.
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.
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.
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.
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.
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.
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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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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
VNC can provide arbitrary desktop sizes and works better over a WAN pipe than X11. Not sure about RDP.
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.
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.
It's also easier to power from a battery and the GPIO pins are potentially handy for monitoring and/or controlling things in a way that is awkward from a modern PC.
Absolutely. Lower power usage is one ting I'm looking for in a computer these days.
Okay, so after giving TightVNC a try for a while, I'm rather liking it. It is fast to connect and start up a desktop. Once you have the settings tweaked to your liking, the desktop looks very crisp and readable. It is also the only way I've been able to run the Mathematica GUI on the RPi. I need to see if I can get this going on my BeagleBone Black. So far, that has been working fine with RDP, but I'm sure I can get tightvnc going there, too. Be sure to check out maxima on Grex. It is reasonably close to Mathematica in syntax. maxima is free and might be helpful to people dealing with mathematics either in school or in their job, or just for fun.
My mathematics tends to be limited to base conversion and Mr. Ohm's law. I use VNC every day and find it very useful, not least because it's cross-platform so I can view my X desktop from whatever I happen to sit in front of: MacOS, Windows, Unix, Linux, Android and probably iOS too. It works the other way as well: I've used it in the past to manage Windows desktops remotely.
I have a Raspberry Pi model B and for Christmas I got a Raspberry Pi 2 model B. Sadly I don't get much time to potch with them. Now there's a Raspberry Pi 3 as well!
Yup, I hear you. The Pi 3, of course, looks interesting. More CPU, for example. The price is still cheap.
Here is an article about using the RPi as a thin client with a Citrix connection. https://www.citrix.com/blogs/2016/02/08/can-the-raspberry-pi-disrupt-the-t hin- client-market-and-the-pc-market/ http://bit.ly/1SKDWWC
Yesterday I hooked up a Raspberry Pi 2 at the office, where it may replace an old Pentium 4 desktop PC. At present I have it booting NetBSD/evbarm from an 8G microSD card. It is (very slowly) fetching pkgsrc onto a USB flash drive. X11 works but I haven't tested video or audio playback yet.
I just got a pi3. Fun little unit. I haven't done anything useful with it yet.
My young neighbor told me they can function as ad-blockers for your router.
RetroPie is a suite of game emulation software that I put on my raspberry pi 2 over the holiday. I had to tweak some settings to get sound to play through HDMI, but after that I could run roms from systems ranging from the original NES to first generation sony playstation and microsoft xbox.
I put 25 Pi3s into a compute cluster. I'm not sure why.
Running simulations? Anyway, sounds like fun.
bitcoin mining?
Not fast enough for that, probably, though if you are patient it might work. The issue is the electricity used costs money and often more than the bitcoin value you get. For a hobby, though, that might not be an issue.
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