Category Archives: Uncategorized

Adaptec 6805H single in a Linux server

In order to extend the amount of SATA disk in my server I decided to use the Adaptec 6805H single Host Bus Adapter (which converts from PCI-E bus to SAS/SATA bus :-)). The device uses a PMC PM80xx chipset. SAS is backward compatible to SATA, one can connect up to 4 devices on a SAS port on this device. The BIOS is not very fast, however my four SATA disks were recognized without any problem. Also, the Ubuntu 13.04 Linux Kernel detected the card with the PCI-ID 9005:8081 using the module pm80xx. Rebuilding of a RAID5 consisting of 4 WD Red 3TB disks went reasonable fast with approximately 130MB/sec. So far, I can recommend that controller for Linux users! Read more »

Install Crazyfly CFClient on Arch Linux (Bitcraze)

In order to run Crazyfly python client (CFClient) some prerequisite have to be installed.

# pacman -S python2 python2-pygame python2-pyqt4

Install libusb from AUR

# yaourt -S python2-pyusb

Also, if you want to get the sources directly from the repository, buy mercurial.

# pacman -S mercurial
$ hg clone https://bitbucket.org/bitcraze/crazyflie-pc-client
$ cd crazyflie-pc-client
$ python2 bin/cfclient

 

Arch Linux on BeagleBone Black from USB-Stick

This guide shows how to install Arch Linux using a USB-Stick. A running U-Boot installation is required, in my case this was U-Boot 2013.04 which came with the original image. Next, I created a memory stick. I followed the documentation of Arch Linux ARM, I just used a USB stick instead of a Micro SD-Card. Now, plug the USB stick into your Beagle Bone Black and press a key to get the U-Boot prompt. U-Boot has the ability to boot from a USB stick, but some custom commands are required. First you need to scan the USB bus system.

U-Boot# usb reset
(Re)start USB...
USB0: scanning bus 0 for devices... 1 USB Device(s) found
 scanning usb for storage devices... 1 Storage Device(s) found

Read more »

Linaro on Arch Linux

In order to use the Linaro ARM cross-toolchain on Arch Linux, some 32-Bit Libraries need to be available. Arch Linux supports multiarch too, just enable the packages in your /etc/pacman.conf:

[multilib]
Include = /etc/pacman.d/mirrorlist

Update your packages

pacman -Sy
:: Synchronizing package databases...
 core is up to date
 extra is up to date
 community is up to date
 multilib 104.5 KiB 148K/s 00:01 [##################################] 100%

Unlike in Debian based distribution the GNU C Library package is called lib32-glibc. Additionally needed libraries by GCC (such as libstdc++6) are included in the package lib32-gcc-libs.

pacman -S lib32-glibc lib32-gcc-libs lib32-zlib

Ubuntu: Bash prompt with Git branch

On several Git Video Tutorials people have these nice colored Git specific Bash prompts. When you are starting to work with Git, you realize that its really helpful to have the branch name around all the time. There easy and also many complex bash prompts out there, e.g. fully customizeable Git prompt scripts, one short scriptone script with functions or just a simple PS1 line.

I created one out of all of these. It shows a standard Ubuntu prompt on non Git directories, and an altered prompt inside git repositories. Inside a Git repository it shows the relative path to the Git’s root directory.

Git bash prompt

Git bash prompt

I created a Gish for it. Simple get it using curl and source it from your ~/.bashrc file:

curl https://gist.github.com/raw/4699573/git_bash_prompt.sh -o ~/.git_bash_prompt.sh
echo ". ~/.git_bash_prompt.sh" >> ~/.bashrc

Pinocc.io Wireless!

Pinoccio scout

Pinoccio scout

There’s a new project building an Arduino compatible micro controller board, called Pinocco. Pinoccio aims to be wireless like the protagonist in the children’s novel Pinoccio. Unlike many other Arduino wannabes the Pinoccio maker try to go the whole mile: The hardware runs on LiPo battery for several days, they extend the board API in order to support easy mesh networking (you wan’t many of them!) and there will be even a message broker API for the board, a MQTT based web service to publish (sensor) data to the web with a RESTful API. The only downside is the price: Starting at 49$ (including battery), its not the cheapest Arduino-like micro controller. But IMHO, given that they engineering things right, its a fair price. I looked a bit deeper at the product, and these points convinced me this is going to be a great product: Read more »

IPv6 with OpenWRT and SixXS (Part 2)

SixXS Logo

SixXS Logo

A week later and my account had enough credits to request the subnet. I got a /48 network, or in otherwords, I have a network with 80 bits which I can use! This are more address then the whole IPv4 address space has! 😎

When you have the approval for the subnet SixXS did allready a lot of work for you: They sent you the actual address, and they make sure that this subnet is routed to your router address. So you only need to assign the addresses to your devices. Read more »

Firefox like keyword search in Chrome

Recently I changed to Googles Chrome browser (to be exact, it’s the open source variant Chromium). Chrom/(e/ium) simply uses less resources, you will notice this when you have a lot of tabs open as I usually do 🙂

Right away I missed my configured keywords for Firefox keyword search. Chrome has that feature too. Here’s how you can add your custom search keywords in Chrome:

  1. Browse to the website you want to search with a keyword (for example http://en.wikipedia.org/)
  2. By clicking with the right mouse button in the URL bar you get a context menu
  3. Click on Edit Search Engines
  4. You get a three column table. Chrome detects the search parameter itself (alternatively you can add the usual “%s”)
  5. In the second column you can set your keyword (e.g. “we” for [w]ikipedia [e]nglish)
Now you can type “we Test” and you will land on the Wikipedia page about “Test”.

Ubuntu virtualisiert mit KVM und hoher Auflösung

Seit einiger Zeit nutze ich nun KVM als Virtualisierungslösung unter Ubuntu und bin absolut zufrieden. Am Anfang habe ich vorallem Windows als Gast verwendet. Bei Windows schalte ich jeweils RDP frei und verbinde dann mit rdesktop auf die virtuelle Maschine. Bei Linux verwende ich die integrierte VNC Lösung von KVM. Damit man höhere Auflösungen als 1024×768 (1280×1024 bei 16-Bit Farbtiefe) verwenden kann, muss man die Option “-std-vga” (Ab KVM-77 “-vga std”) einschalten. Dies emuliert eine Standard VGA Grafikkarte mit VESA VBE 2.0 Unterstützung. Nun muss der entsprechende Treiber installiert und in xorg.conf eingetragen werden:

$ sudo aptitude install xserver-xorg-video-vesa
$ sudo vi /etc/X11/xorg.conf
Section "Device"
    Identifier    "Bochs VESA VBE 2.0"
    Driver        "vesa"
EndSection

Eventuell müssen die Modes noch angepasst werden. Bei mir funktionieren damit Auflösungen bis 1920×1200!