Category Archives: Raspberry Pi

Let’s make an Amazon Alexa device!

Wow, it’s been a while since I posted on here. I’ve been really busy working on programming projects with some of my friends and just haven’t had anything super interesting to blog about.

Enough with that though, let’s get on to what this is actually about! I recently saw a video done by the Youtuber Novaspirit Tech where he takes a Raspberry Pi 2 and implements the Amazon Alexa system!

I’ve had a Pi Model B since a few months after they initially launched and more recently received a Pi 2 from Element14 (you can watch my video reviews of them over on my, admittedly also recently neglected, Youtube channel AEVES Tech) and have been looking for interesting projects to do with them.

This hit the spot perfectly, and so I started out setting up my Pi Model B! Now, most of the tutorials use the Pi 2 as the base device, but my Pi 2 is currently serving as a code server for me, and I didn’t really want to go through the trouble of transferring everything over. Plus, I figured it might make the process a bit more interesting, in case I had to tweak some values.


Setting up the Pi

Obviously, the first thing needed here is to get the Raspberry Pi up and running.

The process of installing Raspbian differs a bit between whatever OS you’re using (Linux, Mac OS X, Windows) so I’m just going to give you a link to the official Raspberry Pi foundation’s page on how to do it.

Once you’ve got the SD card flashed, go ahead and stick it in the Pi. The next part depends on whether or not you want to have the Pi connected over WiFi or not. If you’re planning to just connect over Ethernet then you can skip over this section and move on.

I’ve always used the Edimax EW-7811UN and never had any problems with it on Raspbian, so if you need to buy an WiFi dongle I can definitely recommend this one.

I set up WiFi via the Terminal over SSH, which can be a little bit complicated, so I’m going to go over that here. If you’ve got your Pi connected up to screen and are using the GUI it’s easier.

Once you have terminal access (via SSH over Ethernet or via a Serial to USB cable) you’re going to need to find the SSID for your network. To do this, go ahead and run sudo iwlist wlan0 scan.

This is going to spit out a whole bunch of information, most of which we’re not going to need. Look out for these two lines:

  • ESSID:"networkNameHere"

    This is the network name that you want to connect to. Make sure it’s your network, we’re going to use this value later on.

  • IE: IEEE 802.11i/WPA2 Version 1

    This is the security type. Most modern routers are set up to use WPA2 Personal, and this tutorial will work with both that and WPA, but it may have issues with WPA2 Enterprise or WEP. If your network is set up with WEP, then you’ll have to adjust the setup a bit later on, and you really should think about changing to WPA2.

Now that we have that information, go ahead and run sudo nano /etc/wpa_supplicant/wpa_supplicant.conf and enter the following text:

network={
    ssid="networkNameFromEarlier"
    psk="yourWiFiNetworkPassword"
}

If you’ve got a WEP network, then you’ll need to change out the psk line for wepkey0=your104BitWEPkey. Make sure you don’t put quotes around that key.

To save the file, press Ctrl-X then Y and then Enter. This will save the file. Go ahead and reboot the Pi via sudo reboot.

Once you’ve rebooted, you can check if you’re connected or not via running ifconfig wlan0 and seeing if there is an IP address next to the inet addr field:

$ ifconfig wlan0
    wlan0 Link encap:Ethernet HWaddr 80:1f:02:bf:04:ec 
     inet addr:192.168.0.12 <-- there is a number here Bcast:192.168.0.255 Mask:255.255.255.0
     inet6 addr: fe80::8ec:9767:b412:4a91/64 Scope:Link
     UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
     RX packets:20891 errors:0 dropped:209 overruns:0 frame:0
     TX packets:7167 errors:0 dropped:4 overruns:0 carrier:0
     collisions:0 txqueuelen:1000 
     RX bytes:22347220 (21.3 MiB) TX bytes:996632 (973.2 KiB)

If you have an IP address, then we can move on. Otherwise, make sure you typed the network password correctly in that file and try again.


Setting up Alexa

Hooray! You got the Pi set up, now we get to get started on the fun part, setting up Alexa!

You’re going to need to sign up for an Amazon Developer account, which you can do here. You’ll need to sign in to your Amazon account, and then go to this address: developer.amazon.com/edw/home.html. Once you’re there, click on the Get Started> button for Alexa Voice Service:

Selection_019

From there, you’re going to click on Register a Product and in the drop-down, select Device:

Selection_020

Now, you’re going to proceed through the four parts of the setup process. They’re personal choice for the most part, and the site does a good job of guiding you through, so there’s nothing I really need to explain other than the Web settings part.

This is important because of how you get permission to use Alexa (via OAuth), you have to set up origins and return URLs, otherwise you won’t be allowed to connect to the Alexa voice service. So, you’re going to need your local IP address for the Pi. This is pretty simple to get, just run ifconfig wlan0 | grep "inet addr" (swap wlan0 for eth0 if you’re connecting over Ethernet.). You’re going to want to take the value right after the red text:

Selection_021

In my case, it’s 192.168.0.106.

Take that value and under the Web Settings tab on the Security Profile page:

Selection_024

put that value in like this:

Selection_023

swapping out 192.168.0.106 for whatever IP address you got. Finish up the rest of the setup, and you’re ready to get on to the rest of the setup. Make sure to write down the Device Type ID, Security Profile Description, Security Profile ID, Client ID, and Client Secret – you’ll need them for the setup script later.

I’m using the code from sammachin’s AlexaPi repository, but it’s going to require a few tweaks to actually work. For now, just run git clone https://github.com/sammachin/AlexaPi and it should get the code right off Github!

If you get an error about git not being installed, just run

sudo apt-get update && sudo apt-get install git

and then try again.

Once you get the code, go ahead and type cd AlexaPi and then sudo ./setup.sh. This is going to install a few different required libraries and set up the Python code. You’re going to need the credentials you got from Amazon earlier, so put those in as requested.

Now, the setup script doesn’t work correctly, it doesn’t actually create the required creds.py file, so we’re going to have to manually do that ourselves.

Run mv example_creds.py creds.py and then nano creds.py. You’ll get a file that looks something like this:

# RENAME THIS FILE TO creds.py before use!
import os

#Alexa Settings
ProductID = ""
Security_Profile_Description =""
Security_Profile_ID  = ""
Client_ID = ""
Client_Secret = ""

# Alexa Refresh Token
refresh_token = ''

and put in the information from Amazon where it belongs in the file. Don’t worry about refresh_token still being blank, that gets taken care of in a bit.

If you are logged into your Pi as root, then you’re ready to go, go ahead and skip down to the hardware setup section. If not, read on.

The original code was written to be run as root, but this isn’t exactly good practice, so we’re going to have make a few changes to make it run correctly.

First you’re going to need to edit the startup script in /etc/init.d/alexa, run sudo nano /etc/init.d/alexa and look for the line

python /root/AlexaPi/main.py &

and change out /root for /home/pi. Once you do that, save and exit via Ctrl-X, Y, Enter.


Setting up the hardware

Since the Pi doesn’t have a built-in Microphone port, you’re going to have to use a USB device. It can be a USB microphone or a USB soundcard that has a microphone port. Plug that in, as well as connecting a speaker, either via the Pi’s 3.5mm jack, or via USB.

I’m using my CAD U1 USB microphone, and connecting a speaker up via the 3.5mm jack and it works just fine.

You’re also going to need to hook up a push-button connected to GPIO pin 18 and GND. Part of the terms & conditions of using the Alexa voice service is you can’t have it be voice activated, so we have to manually activate the listening via pressing a button.

Here’s a diagram to show you how to connect it up, if you don’t already know:

pi_alexa


Final Setup

Now that we have the microphone, speaker, and button connected, we can go ahead and finish everything up!

You’re going to need to run sudo python auth_web.py and then go in a webbrowser to yourPisLocalIPAddress:5000. This will redirect you to an Amazon page asking you to log in and then confirm that you want this device to have access to parts of your account. Go ahead and continue through the login process.

After you log in, it should show a page letting you know that it succeeded and you can now reboot your Pi. Go ahead and do that via sudo reboot and wait for it to reboot.

You should now be able to boot your Pi and hear a female voice say “Hello”. Once you hear this, you can press and hold the button and ask Alexa a question!

If you don’t hear this after a while, you may have to SSH in and manually run the script. Just ssh in to the Pi and run

cd AlexaPi && sudo python main.py &

You should hear the “Hello” voice in a bit, and you can go ahead and ask away.

Congratulations, you’ve just created your own Raspberry Pi-based Alexa device!


Conclusion

Is this really useful? I suppose it depends on how you define that.

It’s a bit cheaper to build this than buy the $129 Amazon Tap, especially if you already have all the parts on hand. However, it looks far less pretty and isn’t officially supported by Amazon, so they could decide to end the AVS (Alexa Voice Service) at any time, leaving you with a Raspberry Pi connected to a speaker and microphone.

For the time being, it’s a fun little way to put your Raspberry Pi to use, and, if you really wanted an Amazon Echo and don’t mind a little bit of open circuitry, it’s saves you a little bit of money.

 

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PiTop Status Update – Indiegogo campaign launched today

You may remember a little while ago I posted about a cool new project I had found out about, the PiTop.

As you may remember, the PiTop is a project that gives you all the pieces you need to create a Raspberry Pi (Model B+) powered laptop. From the 3D-printed case, to the 13 inch HD screen, to the built-in WiFi & Bluetooth, you get to create a full-on, portable, Raspberry Pi-powered laptop.

If you want to know more about the project, go ahead and click through on the link above, as this post is just simple status update.

Status update inbound!

So, what’s this status update you’re talking about? Well, it’s that the PiTop’s crowd-funding, indiegogo campaign has been launched. This means you can now back the project, and get early-bird pricing on the product.

Currently $229, the Super Early Bird discount (full kit, including Model B+ Pi) has already sold out and the project is already at 47% of its $80,000 goal. Pretty impressive for the first day and the full goal should be easily reached, with an entire month left.

You can still pick up an early-bird version of the PiTop, albeit sans-Pi, for $209; and a full, non-Super Early Bird version for $249. Information on the project and all of the information about the campaign are available on the project’s Indiegogo campaign page.

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Pi-Top: The DIY, 3D-printed, Raspberry Pi-powered laptop

If you’ve been following the Raspi.Today blog at all you may already know about the Pi-Top. As the title suggests, it’s a Raspberry Pi-powered laptop, that you print and put together yourself.

Various such projects have happened in the past, ranging from Ben Heck’s Raspberry Pi point-and-shoot camera, to a Raspberry Pi-powered tablet by hacker Michael Castor (which, awesomely enough, I got to see in real life at Maker Faire Detroit, which I attended in July)

However, those were far more individual projects, something someone did on their own, for themselves. And this is where Pi-Top differs from the crowd.

Pi-Top:

Pi-Top is different from so many other cool Raspberry Pi-powered projects in that it is something that will hopefully eventually be sold as a kit for people to do for themselves.

“The Pi-Top Kit provides a basis to expand your knowledge in hardware and software innovation. Build and understand your own Raspberry Pi Model B+ powered laptop. We take you through each component and its functionality, so that you can use the Pi-Top as a tool for your own build projects in the future.”.

From the Pi-Top website, pi-top.com.
pi-top team

The Pi-Top Team – Image from Raspi.Today

The process is supposed to a learning experience, all while you are putting together a working, usable every day, project.

“Further your knowledge with our free beginner to advanced Hardware & Software Innovation lesson plans, where we break down complex elements so you can start 3D printing, designing your own PCBs and creating products from start to finish.”

From the Pi-Top website, pi-top.com.

The project boasts some impressive specs, purportedly having a fully integrated laptop keyboard and trackpad as well as extra ports beyond the B+ Pi’s 4 USB, HDMI, audio, a 13.3″ HD screen, and 6-8 hour battery life with WiFi.

The team plans to launch their Indiegogo campaign on the 14th of October, just a week away. I’ll be sure to keep providing updates on this project and maybe even get one of my own (hopefully.)

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Epiphany – A speedy, highly-improved web-browser for the Raspberry Pi

As many of you Raspberry Pi nuts out there may know, the Raspberry Pi has been…lacking in the Web Browser department. If you want features, you had to use Midori, which, although a great browser, was very resource heavy and was not optimized at all. On the other hand, if you wanted speed, you went with NetSurf, but had to give up features. It was an annoying situation to say the least. Yes, you could muck about in config files, tweaking to get performance, but that’s pain for little gain.

Meet Epiphany

Epiphany is the new, improved, optimized, web browser for the Raspberry Pi, developed by the Raspberry Pi Foundation in coordination with Collabora. It is based off GNOME Web, which was previously known as Epiphany.

The first Beta was originally announced back in December of 2013, and it created some hullabaloo in the Raspberry Pi community. In the 8 months since then, the web browser has garnered an impressive set of features, becoming comparable to many full-fledged desktop browsers.

  • First and foremost, hardware-accelerated video decoding and hardware-accelerated video scaling has been added via gst-omx, making Youtube and other video sites useable. During the first beta of Web/Epiphany they were able to get 640×360 videos at 0.5fps, now 25fps 1280×720 videos play smoothly.
  • Next up, Epiphany features Javascript JIT fixes for ARMv6.
  • HTML5 support has been greatly increased.
  • Rendering is much improved, especially in regards to graphics, as new, ARMv6-optimized, blitting functions have been added.
  • Page interactivity and scrolling have been improved (more interactivity while the page is still loading and faster scrolling,) with the addition of progressive tiled rendering.

A full list is available on Marco Barisione’s blog; Marco Barisione being a developer at Collabora, and a member of the team that worked on Epiphany.

In future releases of Raspbian and NOOBS Epiphany will replace the venerable old version of Midori that currently ships with Raspbian Wheezy, but you can also install it to your current installation. Unlike the beta releases, you shouldn’t have to worry about it messing with your installation. However, it is still the first official release, so back up your installation prior to installing Epiphany, just as a safeguard.

The software is already in the Raspbian repositories, no need to muck about with compiling software, just fire up Terminal and enter:

sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get install epiphany-browser

I hope to try this out soon! Let me know down in the comments section what you’ve been using for your web-browsing on the Pi and what you think of Epiphany on Pi!

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It’s been a while since I lasted posted about the Prodigialis Robot project, and while I’m not finished with that, I haven’t worked on it for a while. I’m planning on continuing it later on, but for now it’s on the back burner, one of the reasons being that during development I short-circuited one of the servos beyond use and I haven’t yet ordered a replacement.

However, I’ve recently purchased the PiTFT kit from Adafruit, a miniature TFT+Touchscreen kit for the Raspberry Pi as well as a new Camera Module, and a battery pack. Any idea where this is going? I’m working on the DIY WiFi Raspberry Pi Touchscreen Camera project from Adafruit!

IMG_0148

PiTFT – Soldering Fun!

I heard about the project when it first came out, during January, and really wanted to do it then, but was a bit squeemish about spending $100 on all the parts for a novelty/hobby project. That is, I was a bit squeemish until I heard about the Raspberry Pi Camera photo contest. You can win $314 if your entry is chosen and there are 14 $30 runners-up, with the one catch that you have to use the Pi Camera Module or a webcam attached to the Pi.

Obviously, this was an awesome reason to purchase the parts, and I’m working on setting up the Portable Pi Camera project right now! I’ll try and remember to take photos as I work, though, as many of you may understand, I can get into the project and then never really take a break, even one to snap a few pictures.

Leave a comment down below with any suggestions for this project, features and what-not, and/or any experiences you’ve had with the Pi camera!

New Project coming to town!

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New Raspberry Pi – Model B+

a new Pi

Who’s this? A new Pi? Wot wot?

Heads up Raspberry Pi Enthusiasts! If you don’t already read the Raspberry Pi Blog, or just haven’t checked it lately, I suggest you do so now, as they’ve just announced a new Raspberry Pi! You can read the official post on the official Raspberry Pi blog.

This new Pi isn’t entirely new, quote:

This isn’t a “Raspberry Pi 2″, but rather the final evolution of the original Raspberry Pi.

The original Raspberry Pi being the Model B (512MB of RAM.) However, this doesn’t make it any less cool, at least in my opinion. It still has the same SOC (CPU, GPU, RAM) with all the same specs, so this one isn’t any more powerful. However, it has several new features that I find quite lovely.

New Features on the Model B+

Raspberry Pi Model B+ - USB Ports

Raspberry Pi Model B+ – USB Ports

More USB. We now have 4 USB 2.0 ports, compared to 2 on the Model B, and better hotplug and overcurrent behaviour.

First off the most obvious change is that there are now two double USB ports, giving you have double the room (saying double sounds so much more impressive than two more) to plug in various thingamabobbers like mice, keyboards, WiFi and/or Bluetooth dongles, etc.

Raspberry Pi Model B+ – GPIO Ports

More GPIO. The GPIO header has grown to 40 pins, while retaining the same pinout for the first 26 pins as the Model B

Next, also pretty obvious, is the fact that the number of GPIO ports has expanded to 40! Forty new ports for you to breadboard and interface with, woo hoo! Also, the pinout remains the same for the first 26 GPIO headers, so most of your boards should work with the Model B+!

rpi model b+ audio/composite jack

Raspberry Pi Model B+ – New Audio/Composite video jack

Better audio. The audio circuit incorporates a dedicated low-noise power supply.

An interesting new feature is the combination AUX (Audio) and Composite Video jack. They have combined what used to take up two large port spaces into one, which looks quite nice, and enables the more compact design. Also on the topic of sound, the audio circuit now incorporates a dedicated, low-noise power supply, so all of you using your Pi for sound can get even better sound now!

rpi model B+ power regulating circuit

Raspberry Pi Model B+ – New Power-regulating circuit

Lower power consumption. By replacing linear regulators with switching ones we’ve reduced power consumption by between 0.5W and 1W.

The Pi has new power regulation circuit, which is supposed to be more efficient, dropping power consumption by somewhere between 0.5W and 1W. This is great thing for battery users, as it means their portable projects will be able to work that much longer on one charge! Also, the micro-usb power port has been moved to the right side of the board, sharing space with the HDMI (same spot), the camera port, and the new sound/composite video port.

Raspberry Pi Model B+ - New Micro-SD card slot

Raspberry Pi Model B+ – New Micro-SD card slot

Micro SD. The old friction-fit SD card socket has been replaced with a much nicer push-push micro SD version.

One of the issues with the previous evolution of the Model B was that the SD card slot was a plastic, friction-fit, slot that was prone to breakage. Not anymore, the Model B+ has a fancy, new, metal , Micro-SD card slot. And yes, I meant Micro-SD, the Model B+ no longer uses full SD cards, it uses the new push-push Micro-SD card slots. For the NOOBS users out there, don’t worry. NOOBS will still work. All you have to do is take the Micro-SD card out of the full SD card adapter and stick it in your Pi. Right as rain!

Neater form factor. We’ve aligned the USB connectors with the board edge, moved composite video onto the 3.5mm jack, and added four squarely-placed mounting holes.

One final thing to mention is that, as you probably noticed already, is that the general form has changed. It’s still the same size (credit-card), but they’ve re-arraigned the ports. There are no longer any ports hanging off the front and left sides of the Pi, everything has been moved to the rear and right. This may be useful for case designers and embedders, or it could be a bane. Time will tell.

And, don’t fear, the regular Model B will still be in production while there is still a demand.

Production and community reviews

Supposedly you can purchase the Model B+ from the usual distributors (Farnell/Element14/Newark and RS/Allied Components) but I’ve had issues with Element14 not showing the price, not sure if that’s something on my end, or if it’s similar to what happened opening-day. Also, according to the blog it will be the same price as the current Model B, $35. However, the price on
Element14 is $50. Not sure what that’s all about.

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CamJam EduKit – beginning electronics for under $10

camjam edukit

CamJam EduKit – Introduction materials for electronics hacking

Say hello to the CamJam EduKit, a new product from The PiHut. Basically put, it’s a can that includes some of the basic parts that every aspiring/beginning hacker/maker needs to get started on breadboarding. From The PiHut’s site:

The CamJam EduKit features the following components all neatly packaged in a tin:
•A 400pt breadboard
•3 LEDs (Red, Yellow and Green)
•A button
•A buzzer
•Resistors and jumper cables
For under $10 ($8.58 to be exact), you get all that? That’s a pretty good deal, I have to say.
The idea was actually thought up by Michael Horn of the Raspberry Jams (which the USA, by the way, needs a couple of) and about the same time Jamie Mann of The PiHut had the same idea. So, they ended up collaborating, Jamie Mann procuring the parts and assembling the kits, Michael Horn writing the worksheets and testing them.
The worksheets I’m talking about are simple projects that you can do with the JamCam’s contents, a good starting point for parents and teachers wanting to get their children/students involved in electronics, with minimal effort.
I linked above to the CamJam, but in case you missed it, here’s another link to the CamJam EduKit on PiHut. Even if you haven’t purchased the EduKit you can still access the worksheets for free, and they don’t explicitly require the EduKit to work, just the components.
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Raspberry Pi Today – Raspberry Pi Podcast

I listen to the Ubuntu UK Podcast (which, by the way, is a great little podcast for keeping up with Ubuntu/Linux/FOSS news – clean, fun, and informing) and they mentioned a new Raspberry Pi podcast, Raspberry Pi Today. (That link. Click it. Check out the Podcast, it’s actually good.

raspi today logo

Raspberry Pi Today – Logo

I figured I would check them out, seeing as there wasn’t any other podcast like it at the time, and I have to say it was quite nice! I’ve only listened to the first two at the time of this post, but I’m definitely going to be listening to more. There are currently four episodes, three of which were mass-released on the same day.

The podcast really isn’t that old, having been officially started (or at least episodes released) on June 24th. The 4th, and most recent, episode was released just four days ago, on July 4th (Happy 4th of July y’all!), and they should continue to come out weekly.

From what I heard on the first episode and see in the descriptions, these podcasts are going to be mainly interviews; in the first he interviews Carrie Anne Philbin (aka…Geek Gurl) and in the second he interviews Ben Gray of Phenoptix.

You can visit the official site, Raspi.Today which I linked to above, to download all of the episodes. It’s also serves as his Raspberry Pi/hobby blog. I’ve also linked to all four of the episodes below (in iTunes, SoundCloud, and direct download.)

Podcasts

All podcasts can be accessed on the Podcast page of the site, as well as following the RSS feed.

Subscribe & Download for free:
iTunes
SoundCloud

  1. Adventures in Raspberry Pi:
  2. Screwdrivers & enthusiasm:
  3. AKA Theremin Hero:
  4. HDYourPi:

Check ’em out, and give the support that this needs, it’ll be great to have a well-done Raspberry Pi podcast!

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Raspberry Pi Compute Module dev kits now available for sale!

A while ago the Raspberry Pi foundation announced a new product, the Raspberry Pi Compute Module. Essentially, it’s the Pi’s core (CPU/GPU/RAM) as well as a 4Gbyte eMMC Flash device (serves as the SD card would on a regular Pi,) on a board the size of a RAM chip (67.6x30mm board – standard DDR2 SODIMM connector – same as for laptop RAM.) The Compute Module was, quote Official Raspberry Pi Blog:

The Compute Module is primarily designed for those who are going to create their own PCB

In that same post the foundation announced they were working on a development kit, also known as the IO board (shorthand, the CMIO) that you can plug the CM (Compute Module) into to develop on and experiment on the CM before going to the expense of fabricating a full PCB.

That post was back at the beginning of April (the 7th to be exact) and now, as of June 23rd, the CMIO (Compute Module IO board) is available for sale from RS and Element14 in the form of a dev kit. The kit, which goes for MRP $200, comes with the IO board (obviously), a Compute Module, adapters to convert the CMIO board camera and display interfaces to connect to the Raspberry Pi Camera (and the display, which is hopefully coming later this year,) as well as a 5V power supply and a micro USB cable for flashing the eMMC from a host PC.

cmio dev board

Compute Module Development Boards Development Kit – Also includes 5V power supply & MicroUSB cable – those aren’t shown

As of the official release post the only operating system that is “Compute Module Aware” is the latest version of Raspbian (as of 6/20/2014.) You’ll have to grab that and flash it onto the Compute Module. Work is being done to make the other OSes usable. Right now using NOOBS or any of the others will probably not work, but YMMV.

The foundation is working on the software stack to make developing easier on the Compute Module. There is a new system in the works to make remapping the GPIO pins, which have closed source code, much easier. Also in the works is the ability to use dual cameras. Basically put by the foundation, early adopters – if it works on a Pi now, it will work on the CMIO board. Dual cameras or screens or any other interfaces that don’t work on the Pi almost definitely aren’t working on the CMIO board either or will be far more tricky to do than they will be.

To get started with your Compute Module Development Kit you can head on over to the official Raspberry Pi Compute Module documentation. Also, the foundation says to feel free to post questions on the forum.

 

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I use my Raspberry Pi as a headless server, and thus SSH in all the time. While I can shut down the Pi and remove the SD card to load files on, or use a USB stick, those require accessing the Pi (and in the case of the USB stick – running wires to a USB hub.) This can be a pain, so if I need to download a file I just use wget.

It comes installed with Raspbian by default as far as I know. It makes sense that it would, as so many core software rely on it. Thusly, I use it download files from the internet or, if I need to put a file on it from my Ubuntu laptop, I just pop the file into my local server and download it onto my Pi. Works great!

However, there is one issue that I have run across, and that is that just running a simple wget command like

wget soandso.com/thisZIP.tar.gz

results in an error:

Resolving dl.dropboxusercontent.com (dl.dropboxusercontent.com)... failed: Name or service not known.
wget: unable to resolve host address `dl.dropboxusercontent.com'

Kind of issue, you might say. It took me ages to figure this one out, but finally I discovered that if you add the -4 flag to the command, it forces wget to use IPv4 addresses, thus resolving the issue and allowing downloads to happen!


Bonus Tip!
If you are downloading a large file and the download gets interrupted, tack on the -c flag on the wget command and it will continue from where you left off. Pretty nifty, eh?

Raspberry Pi Tech Tip #1 – Fix Unable to Resolve Host Address error for wget on Raspbian

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