Within this article, we describe how we have set up an embedded debian (SID) on a mini2440 / friendlyarm development board, and how we have installed all the fun stuff, as Java and the JNI (native interface), X11, the GCC/G++ toolchain and much more.

We will use a SD-Card to store the root file system (just because of the bigger storage size)
Therefore we have to create the partitions on the card:

Bootloader

We will use the standard bootloader provided (vivi).

First of all, we have to set up the boot parameters properly. This is done using the serial console and supervivi. Switch the boot-switch to NOR and power on the mini2440. On the serial console, you will now get the output of the supervivi console:


##### FriendlyARM BIOS 2.0 for 2440 #####
[x] format NAND FLASH for Linux
[v] Download vivi
[k] Download linux kernel
[y] Download root_yaffs image
[a] Absolute User Application
[n] Download Nboot for WinCE
[l] Download WinCE boot-logo
[w] Download WinCE NK.bin
[d] Download & Run
[z] Download zImage into RAM
[g] Boot linux from RAM
[f] Format the nand flash
[b] Boot the system
[s] Set the boot parameters
[u] Backup NAND Flash to HOST through USB(upload)
[r] Restore NAND Flash from HOST through USB
[q] Goto shell of vivi


We use s to set the boot parameters:
The press s, then “linux_cmd_line” to set the boot parameters appended to the boot arguments of the linux kernel.

The boot arguments are:

console=ttySAC0,115200 noinitrd root=/dev/mmcblk0p2 rootwait=4 rw ip=dhcp

This tells the kernel to mount the second partition of the SD-Card as root file system (read-and-writeable)

Own Kernel

Building your own kernel, requires you to have a working cross compilation environment. Please take a look at: http://www.friendlyarm.net for the toolchain.
You can optain the used config file here: download Kernel config

Simply copy the config file into your kernel source directory and name it “.config”. Then compile your kernel. The kernel will be located in /arch/arm/boot after compilation. Then simply upload the kernel with the provided tool of friendlyarm:

in the supervivi console press “k” and start the upload through “USB” on your pc.

Your new kernel is now flashed into the NAND storage of your mini2440/friendlyarm.

Debootstrapping Debian

Note, this article is based upon: http://code.google.com/p/mini2440/wiki/Emdebian
Download Kernel config

Today I had to use an Ative Record implementation for C#: Castle Active Record. It worked verfy fine until i needed to save a one to many relationship. Then the underlying NHibernate yielded the following Exception:
StaleStateException: unexpected row count -1 expected 1 .

Googling for that Exception gave me two options: At first, turning the sql servers NOCOUNT property OFF by either sending “SET NOCOUNT OFF” or setting the appropriate property of the SQL-Server in the config dialog. Both did not work for me, as i am neither the Admin of the server nor i can send the command by hand through the many layers introduced by ActiveRecord/NHibernate.

Another possible solution was overriding the connection driver to let i send the query everytime the connection gets requested. This was proposed by the blog author of: http://www.socialanimal.com/archives/2008/03/07/nhibernate-and-nocount/. This either didn’t work for me.

But taking a look in the database suprised me! My Data was actually written! So a simply try {} catch(…) { //ignore } did the job!

SHAME ON ME FOR THAT

Part 1 of the development series:

First of all, we need to setup the development environment. This is provided by Samsung as Eclipse-Plugin.
Therefor we need to download eclipse (The Java EE Edition!) (http://www.eclipse.org/downloads)

After downloading and setting up eclipse, install the Samsung Widget Developer SDK:

Within Eclipse, click on Help, then Install new Software.

Add the following URL: http://widget.samsungmobile.com/sdk/ and install the plugin!

That’s it, you can now start to develop Samsung TouchWiz Widgets!

Part 2 will cover a short sample project!

Recently i had to implement Base64 en & decoding using openssl’s bio library, which by the way is just great, but a little “under-documented!”

If you ever wondered, why the standard example of decoding base64 data always returns 0 when using it with your test data? Well there is some nice undocumented feature: Strings that do not end with a newline ‘\n’ are not processed! So you have two possibilities: adding a newline to the string or use the following flag:

BIO_set_flags(BIO* to your bio_f_base64, BIO_FLAGS_BASE64_NO_NL);

Edit: 21/Dec/08:

After handin of the courses homework i can now give some details about how to do it:

Using a chain of BIO filters is the most flexible way to handle proper base64 en-/decoding:


//write base64 coded data to stdout
BIO* b64 = BIO_new(BIO_f_base64());
BIO* bio_out = BIO_new_fp(stdout, BIO_NOCLOSE);
bio_out = BIO_push(b64, bio_out); //attach output bio to base64 bio
BIO_write(bio_out,"data",sizeof("data"));
BIO_flush(bio_out); //flush the buffer
BIO_free_all(bio_out); //cleanup!


For more information see the super perfect documentation: http://www.openssl.org/docs/crypto/BIO_f_base64.html

Today i had to access a matlab script from a java program. After some hours of trying to get it work by using matlabs command line i found a method to call a matlab script without using the command line. Using matlab -r “functionName” didn’t work because of some unknown charset erros i haven’t found till now. The basic idea is based on this blog-post.

Therefore, a process must be created:


String command = "matlab -nosplash -nodesktop";
Process process = Runtime.getRuntime().exec(command);


Afterwards we obtain the standard-input of the process and send a command to be interpreted by matlab:


BufferedWriter out = new BufferedWriter(new OutputStreamWriter(process.getOutputStream()));
out.write("function_to_be_executed");
out.write("\n");
out.write("exit;") // this will close matlab after the execution finished!


If you like to see what is happening, try to read from the process.getInputStream()

hope that helps some of you!

Today i found a solution to use both my notebooks display [1440x800] (Dell Vostro 1510 with NVidia 8400M GS) and my flatpanel tft [1280x1024] under Ubuntu 8.04.

This is what my xorg.conf looks like (only the important parts!)

Section “Screen”
Identifier “Default Screen”
Device “nVidia Corporation G80 [GeForce 8400M GS]”
Monitor “Generic Monitor”
DefaultDepth 24
Option “TwinView”
Option “MetaModes” “1440×900 1280×1024″
Option “TwinViewOrientation” “LeftOf”
SubSection “Display”
Modes “1440×1440″
EndSubSection
EndSection

Section “Screen”

# Removed Option “metamodes” “CRT: nvidia-auto-select +1440+0, DFP: nvidia-auto-select +0+0″
Identifier “Screen0″
Device “Videocard0″
Monitor “Monitor0″
DefaultDepth 24
Option “TwinView” “1″
Option “TwinViewXineramaInfoOrder” “DFP-0″
Option “metamodes” “CRT: 1280×1024 +1440+0, DFP: nvidia-auto-select +0+0″
EndSection

This config was partially done using: nvidia-settings (apt-get install nvidia-settings)

As i recently got my new Dell Vostro 1510 and encountered some problems when using Ubuntu 8.04 i decided to create a post about my experiences and create a checklist and link to people who have solved some problems mentioned!

So this is my system:

Dell Vostro 1510

• Intel Core 2 Duo T8300 (2.4 GHz, 3 MB L2-Cache)
• 3 GB Ram
• 1440×900 WXGA+
• CardReader (SD/MMC/MSPro)
• Front-Side Mic&Headphone jacks
• 2 Megapixel Webcam
• 4x USB (2left,2right)
• 1394 (right)
• NVidia Geforce 8400M GS

Checklist:

(1): Lan: Sometimes it seems that the gnome-network-manager won’t work. Using dhclient (sudo) on console helped me!

If it doesn’t work though try this: http://www.martinhenze.de/2008/05/24/ubuntu-linux-on-dell-vostro-1510

(2) Thank you Ignacio for reporting this!

(3) RE-starting your current runlevel brings X back to live! (CTRL-ALT-F7)

What i already found out, is that my Sony DSC-W30 is not correctly mounted (sometimes waiting for an update just does the work)

Edit: Cardreader works out of the Box.

LAST EDIT: 09 of Jan.09

Recently i got my new Dell Vostro 1510.

Ubuntu 8.04 works out of the box, only my microphone isn’t working, and the speakers aren’t muted, when plugging in the headphone. So the next few post will cover my battle against Ubuntu and the ALSA drivers

00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 0c)
00:01.0 PCI bridge: Intel Corporation Mobile PM965/GM965/GL960 PCI Express Root Port (rev 0c)
00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 03)
00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 03)
00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03)
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)
00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03)
00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 03)
00:1c.3 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 4 (rev 03)
00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 5 (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03)
00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03)
00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3)
00:1f.0 ISA bridge: Intel Corporation 82801HEM (ICH8M) LPC Interface Controller (rev 03)
00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 03)
00:1f.2 SATA controller: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA AHCI Controller (rev 03)
00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 03)
01:00.0 VGA compatible controller: nVidia Corporation GeForce 8400M GS (rev a1)
06:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or AGN Network Connection (rev 61)
07:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 02)
08:05.0 FireWire (IEEE 1394): O2 Micro, Inc. Firewire (IEEE 1394) (rev 02)
08:05.2 SD Host controller: O2 Micro, Inc. Integrated MMC/SD Controller (rev 02)
08:05.3 Mass storage controller: O2 Micro, Inc. Integrated MS/xD Controller (rev 01)

First I installed the backports, as this blog post suggests: http://linuxtechie.wordpress.com/2007/10/19/getting-intel-ich8-family-rev-3-sound-card-to-work-in-gutsy/

sudo apt-get install linux-backports-modules-hardy

# not -generic (named different now!)

Edit:

inserting the following line to /etc/modprobe.de/alsa-base did a great job for now:

options snd-hda-intel model=toshiba position_fix=0 enable=yes

The microphone still has a litte problem, as it seems that is faaaaaaaar to loud, so recording with the mic gives me just garbage noise (but i can identify my words [that they start & end] ), but muting the speakers now works!

Edit2:

Microphone now works: just turn down PCM to about 1/3 and increase mic-boost to 100.

Edit3: (5th of July)

Check if no channel is muted (using alsamixer on console!)

So,

wieder einmal in Rästel gelöst!

Meine Netzwerkkarte vom Typ Realtek 8139 hat unter Linux nicht funktioniert. Der Grund: Der Windowstreiber hat das Gerät deaktiviert, und die Linuxtreiber konnten das Gerät nicht mehr aktivieren.

mehr dazu:
C’t – FAQ

And as this happend more often:

If your Realtek lan-port doesn’t work after running a microsoft os try disabling any power-saving options the realtek windows driver offers! See the link above for screenshots!

Hin und wieder kann es vorkommen, dass man hinter einem Gateway sitzt, der einem nicht erlaubt, gewisse Dienste zu benutzen, oder auf gewisse Server zuzugreifen. Kann man dies jedoch vom Gateway aus tun, so spricht auch nichts dagegen via SSH die Verbindung vom Client über den Gateway zum Server zu tunneln.

Wie geht das?

ssh bietet hier die Möglichkeit einen solchen Tunnel aufzubaue, und zwar mit dem Kommandozeilenargument -L:

ssh -L localport:server:serverport user@gateway

Zum Beispiel:

ssh -L 9000:stupent.at:80 ich@mein.gateway.com

Dadurch kann man nun vom bösen Client aus, der normal nicht auf stupent.at zugreifen darf, mittels http://localhost:9000 zugreifen.

Eventuell hilfts ja wem!