Tag Archives: Raspberry Pi

Monitoring your Gas Consumption with a JeeNode and a nRF24L01+

via Hack a Day» hardware

[Sven337] just blogged about a gas consumption monitoring setup he finished not long ago. As his gas meter was located outside his apartment and nowhere near any electrical outlet, a battery-powered platform that could wirelessly send the current consumption data to his Raspberry Pi was required. His final solution therefore consists of a JeeNode coupled with the well known nRF24L01+ wireless transmitter, powered by 3 supposedly dead alkaline batteries.

[Sven337] carefully looked at the different techniques available to read the data from his meter. At first he had thought of using a reflective sensor to detect the number 6 which (in France at least) is designed to reflect light very well. He then finally settled for a magnetic based solution, as the Actaris G4 gas meter has a small depression intended for magnetic sensors. The PCB you see in the picture above therefore has a reed sensor and a debug LED. The four wires go to a plastic enclosure containing the JeeNode, a couple of LEDs and a reset switch. Using another nRF24L01, the Raspberry Pi finally receives the pulse count and reports it to an eeePC which takes care of the storage and graphing.

Filed under: hardware, Raspberry Pi

Arduino-compatible, quad-core ARM dev board

via Hack a Day» hardware


The Advent of the Raspberry Pi has seen an explosion in the market for ARM dev boards, sometimes even with pinouts for Arduino shields. The UDOO, though, takes those boards and ramps up the processing power for some very, very interesting builds.

The UDOO comes equipped with a dual or quad-core ARM CPU running at 1GHz with 1 GB of RAM. Also on board is the Atmel SAM3X8E – the same chip in the new Arduino DUE - and has pinouts for all those Arduino shields you have lying around.

In addition to serving your next project as a souped-up Raspberry Pi, UDOO also includes 78 (!) GPIO pins, Gigabit Ethernet, a camera connector, one SATA port (on the quad-core version), and an LVDS header for attaching LCD monitors. Basically, the UDOO is the motherboard of an ARM-powered laptop with the pinouts to handle Arduino shields. It’s just like [Bunnie]‘s laptop, only this time you can actually buy it.

The UDOO doesn’t come cheap, though: on the UDOO Kickstarter, the dual-core version is going for $150 while the quad-core is priced at $170. Still, if you need the power to run a pair of Kinects or want to build an awesome torrent box, you’d be hard pressed to find a more powerful board.

Filed under: ARM, hardware

An overkill network adapter for retrocomputers

via Hack a Day» hardware


If you want to get an old Apple, Commodore 64, Amiga, or any other retrocomputer up on the Internet, this is for you. [Stian] had an Amiga 500 lying around and wanted to put it on a network. The A500 isn’t expandable, so he needed to look at some sort of adapter to put it on a network. The solution came to him in the form of a Raspberry Pi, a null modem cable, and a few bits of software.

To connect his Amiga to his network, [Stian] made a small serial converter board for his Raspi that breaks out the Tx and Rx pins on the Pi to a 9-pin serial port. With the physical connection to the Pi made, the only thing left to do was to get some software for the Amiga, namely AmiTCP and PPP. It’s not exactly a fast network connection, but this build allows [Stian] to connect to WiFi networks with ancient hardware.

One interesting aspect of [Stian]‘s build is the fact it’s completely transferable to other retrocomputers – everything from old S-100 bus computers to classic macs, apples, and pretty much anything else with a serial port that supports PPP. Even with the expense of a Raspberry Pi, it’s much cheaper than absurdly expensive second-hand SCSI to Ethernet controllers and other tomfoolery.

Filed under: hardware, Raspberry Pi

Homebrew GPS gets ±1 meter resolution with a Raspberry Pi

via Hack a Day» hardware


We’ve been following the work of [Andrew Holme] and his homebrew GPS receiver for a while now. A few years ago, [Andrew] built a four-channel GPS receiver from scratch, but apparently that wasn’t enough for him. He expanded his build last year to track up to eight satellites, and this month added a Raspberry Pi for a 12-channel, battery-powered homebrew GPS receiver that has an accuracy of about 3 feet.

The Raspi is attached to an FPGA board that handles the local oscillator, real-time events, and tracks satellites automatically. The Pi handles the difficult but not time-critical math through an SPI interface. Because the Pi is attached to the FPGA through an SPI interface, it can also load up the FPGA with even more custom code, potentially turning this 12-channel receiver into a 16- or 18-channel one.

An LCD display attached to the FPGA board shows the current latitude, longitude, and other miscellaneous data like the number of satellites received. With a large Li-ion battery, the entire system can be powered for about 5 hours; an impressively portable GPS system that rivals the best commercial options out there.

Filed under: hardware, Raspberry Pi

Raspi astrophotography board also does everything else

via Hack a Day» hardware


A few years ago the folks at Astro Designs put together a board that took off-the-shelf CCD sensors from point and shoot cameras and turned them into respectable astrophotography sensors. Since then, the world has seen an explosion of Raspberry Pis, Arduinos, and other microcontroller platforms, making this the perfect time for a hardware revision.

Their PiXi-200, like their previous AstroCam board, is able to take image sensors out of cameras and turn them into telescope mounted cameras. That’s only one of its tricks, though: The PiXi-200 also has accelerometers, gyroscopes, enough UARTs to do just about anything, a four channel ADC and four channel DAC, two dozen GPIO pins, enough LEDs and buttons for any project, and a 200,000 gate FPGA. All this in a board that plugs directly into the GPIO pins on the Raspberry Pi just like an Arduino shield. Needless to say, there’s a lot you can do with this board.

Right now, the design is still in the prototype stage, but once everything is finalized the basic model of the board will sell for £30 GBP ($50 USD). The high-end “Model C” board, with all the bells and whistles, will sell for £45 GPB ($70 USD).

Filed under: hardware, Raspberry Pi

Paperduino Pi

via Arduino Blog

This is a project for people a little bit skilled in soldering and design PCB. The user [dernulleffekt] designed an homemade shield for Raspberry Pi that integrate an Arduino Board.

The Paper-Duino-Pi is an Arduino shield for the Raspberry Pi. Due to the fact that it is designed as Paper-PCB it is easy to create and one doesn’t need a printed circuit board. Some small modificaten in the OS and IDE and you have a perfect interface for the Raspberry Pi.

This [video] shows how one can use it with the Firmata and Pure Data. On the [website] there is a very well written tutorial to build your Raspberry/Arduino shield at home.

Arduino Beer Keyboard

via Arduino Blog


Our friends from Romania send us this:

Do you know what you get if you combine 44 beer cans with an Arduino board and a Raspberry PI ? I tell you : fantastic user engagement!

It happened at Webstock, event which took place in Bucharest this month. Staropramen, one of the sponsors of the event asked us for an innovative way to offer a trip to Prague to one of the event’s guests.

So, we came up with a keyboard made out of 44 Staropramen beer cans. Each beer can was a key, and whenever someone touched it, the corresponding letter appeared on a large plasma screen (just like any regular computer keyboard).

And the surprise was fantastic! The user experience and engagement overcame any expectation. Every single person who attended Webstock tried the keyboard and participated to the contest.

Behind the scene, the system is built around an Arduino board and a few capacitive controllers (just like the ones which are inside smartphones’ touch screens), connected to a Raspberry PI board which controls the plasma screen display.

Other hardware we used was the Sparkfun MPR121 Capacitive Touch Sensor Breakout Board (4 of them, each controlling 11 beer cans) and one Sparkfun MP3 Trigger Board which controls the sound effects.

A movie and some photos took during the event can be found on the [website]
(feel free to use them if you want, or download directly the photos as a zip archive).

[Webstock] is the biggest blogging and social media event in Romania.

[Robofun Create] is a Romanian company specialised in creating cool on-demand technology products.


Olimex OLinuXino: Fast and Open

The PCWorld website posted an article about the open hardware Olimex OLinuXino single board computer. The article compares it to the Raspberry Pi, noting that the while Raspberry Pi hypes their board as open hardware, they have not released their CAD files or complete schematics yet and utilize components that are not available in small quantities. Olimex designed the OLinuXino board to address some of these concerns. All CAD files and complete schematics are available and they use an easy to find CPU. They use the Creative Commons Share-Alike license for all hardware and the GNU GPL license for all software associated with the OLinXino. The board uses a faster CPU than the Raspberry Pi and runs Android, debian, and other GNU/Linux distros. They also tout the board as being noise immune and working in industrial environments with a temperature range of -25 C to 85 C. The OLinuXino uses the standard nano-ITX form factor. The board is priced at 45 Euros (about $57). One point where we’d have to say the Raspberry Pi wins is on the name. It’s unclear how to pronounce OLinuXino, which can’t be good from a marketing standpoint.

So what about the actual specifications?

  • A13 Cortex A8 processor at 1GHz, 3D Mali400 GPU
  • 512 MB RAM
  • 6-16VDC input power supply, noise immune design
  • 3 + 1 USB hosts, 3 available for users, 1 leads to onboard pinout
  • 1 USB OTG which can power the board
  • SD-card connector for booting the Linux image
  • VGA video output
  • LCD signals available on connector so you still can use LCD if you diasble VGA/HDMI
  • Audio output
  • Microphone input
  • RTC PCF8536 on board for real time clock and alarms
  • 5 Keys on board for android navigation
  • UEXT connector for connecting addtional UEXT modules like Zigbee, Bluetooth, Relays, etc
  • GPIO connector with 68/74 pins and these signals:
    • 17 for adding NAND flash;
    • 22 for connecting LCDs;
    • 20+4 including 8 GPIOs which can be input, output, interrupt sources;
    • 3x I2C;
    • 2x UARTs;
    • SDIO2 for connectinf SDcards and modules;
    • 5 system pins: +5V, +3.3V, GND, RESET, NMI
  • Optional low-cost 7″ LCD with touchscreen

Maker Shed Now Shipping 512MB Raspberry Pis!

via MAKE » Category: Open source hardware

800px-RpiFront512MB Raspberry Pi Model B Version 2.0s have just arrived in the Maker Shed! This is the newest model that was released by the Raspberry Pi Foundation on October 15h. It's available for purchase today and ships out immediately.

Read the full article on MAKE

Raspberry Pi Boards and Starter Kits Now Available in the Maker Shed!

via MAKE » Category: Open source hardware

RaspberryPiLabelAre you bummed you couldn't get to Maker Faire New York to get a Raspberry Pi? Don't fret, they are now available online in the Maker Shed!

Read the full article on MAKE

Tiny WiFi Adapter for Raspberry Pi

via Wolf Paulus » Embedded

[Updated on Feb. 2. 2013 for (2012-12-16-wheezy-raspbian) Kernel Version 3.2.27+]

The extremely small EW-7811Un USB wireless adapter looks like the perfect WiFi adapter for the Raspberry Pi. Not only is it tiny and relatively inexpensive, it also seems capable enough to be a great companion device for the Raspi. While elinux still shows that some users report timeouts trying to initialize the module, I cannot verify this with 2012-12-16-wheezy-raspbian.

WiFi is not really necessary for the Raspberry Pi. It already comes with an ethernet port, provides RS-232 (aka serial-) connectivity, and has two USB ports. However, in case you wanted to add WiFi to the Raspi, this little adapter seems to be as good as any. Here is why:

The Edimax EW-7811Un

  • complies with wireless IEEE802.11b/g/n standards
  • adjust transmission output by distance and CPU offload, to reduce power consumption when wireless is idle
  • is currently the smallest wireless adapter
  • currently cost between US$ 9 and US$ 15

more than enough reasons to cut the cord and add WiFi connectivity to the Raspberry Pi.

After performing the usual initial configuration in raspi-config, using WiFi Config (a GUI tool sitting at the desktop when starting LXDE with startx) is by far the easiest way to get the Edimax EW-7811Un configured.

But let’s quickly run through the steps of creating that bootable SDCard before dealing with the actual WiFi issues:

Creating that bootable SDCard

  1. Download the image file from http://www.raspberrypi.org/downloads
  2. Unzip the file to get to the image file.
  3. df -h to determine which drive is used for the sdcard, e.g. integrated SDCard Reader turned out to be disk2 for me.
  4. sudo diskutil unmount /dev/disk2s1
  5. sudo dd bs=1m if=/Users/wolf/Downloads/2012-12-16-wheezy-raspbian.img of=/dev/rdisk2
  6. sync
  7. sudo diskutil eject /dev/rdisk2

On a class 10 SD Card, the whole process shouldn’t take much longer than 70 seconds maybe. Insert the SDCard into the Raspi, power up, boot, and use the on screen menu:

In case you need to do this over a network, the Raspberry Pi’s default hostname is raspberrypi. I.e.
ssh pi@raspberrypi .. the pasword is raspberry

sudo raspi-config

  • Expand root_fs
  • Change password
  • Change locale to EN_US.UTF-8 UTF-8 (un-select english UK and select select in long list)
  • Set Time zone (America / Los_Angeles)
  • Change memory split to 128:128
  • Enable ssh

Finally reboot: sudo shutdown -r now
Running the raspi-config again to execute update feature, reboot and login.
Now finding more updates and upgrades like so:

sudo apt-get update
sudo apt-get upgrade

Changing the PI’s hostname

Edit the host name in these two locations:

  • sudo nano /etc/hostname
  • sudo nano /etc/hosts

Adding WiFi support / EW-7811Un

With previous wheezy builds, I had to install the realtek firmware, blacklist the already installed 8192cu driver and install a new one. Not this time. ifconfig shows the wlan0 interface and iwlist wlan0 scan can be used to scan for available Wifi access-points, without any firmware installation or driver updates.


All what’s needed to do to connect the Raspberry Pi to a Wifi Network, is to add a network configuration to /etc/wpa_supplicant/wpa_supplicant.conf.

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

The network configuration depends very much on your network, SSID, Password Security etc. However, here is what I have added, to make the EW-7811Un connect to my WiFi network:


With the correct WiFi network configuration added to the wpa_supplicant.conf file, the ethernet cable can be removed and the Raspberry Pi will automatically switch over to WiFi.
This behavior is pre-configured in /etc/network/interfaces, which looks something like this:

auto lo

iface lo inet loopback
iface eth0 inet dhcp

allow-hotplug wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet dhcp

Raspberry Pi – WiFi (Edimax EW-7811Un)

Backup the SD Card

Once done with setting up Raspian, I usually create an backup image that later can be copied onto the same or a different SD Card (of equal size).


Insert the perfect SDCard into the Card Reader and find out how to address it. Again, for me that usually is disk2s1.

sudo diskutil unmount /dev/disk2s1
sudo dd bs=1m if=/dev/rdisk2 of=~/RASP_3_2_27.img
sudo diskutil eject /dev/rdisk2

Depending on the size of the SDCard, this will create a huge file (like 16GB) an may take a while (like 7min).

Restore or Copy

Insert am empty SDCard into the Card Reader and find out how to address it. Once again, for me that usually is disk2s1.

sudo diskutil unmount /dev/disk2s1
sudo dd bs=1m if=~/RASP_3_2_27.img of=/dev/rdisk2
sudo diskutil eject /dev/rdisk2