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World Statues Festival Arnhem 2011

Tjeerd — Sun, 23 Oct 2011 17:52:16 +0000

Last month I visited the World Statues Festival in Arnhem. More than hundred people from all over the world presenting themselves as statues. The weather was great and it was very crowded. Ester and I took some pictures which you can find here.

Guruplug boot and kernel upgrade for stable Wi-Fi

Tjeerd — Wed, 29 Dec 2010 10:41:13 +0000

Recently I got my Guruplug Server Plus device and I am happy with the toy, but soon I discovered that the Wi-Fi drivers are not stable if you want to run the device in “client mode”, I found out that recently there has been put up a page with instructions to make the device Wi-Fi stable. Although the instructions are there, it was difficult for me to find the right way to upgrade the U-boot and kernel. So here the way I did it. In a next posting I will explain how to setup Wi-Fi correctly, still figuring that out.

Prerequisites:
- Guruplug connected to your network via ethernet and a JTAG module to allow serial console access to the device
- Computer connected to your network (probably also the computer you want to use to access your Guruplug via the serial console)

Part 1: setting up the TFTP-server and putting the images in the right place

- Download pre-compiled U-boot binary here (direct link) into a directory (e.g. /root/guruplug)
- Download pre-compiled binary kernel here (direct link) into a directory (e.g. also /root/guruplug)
- Install a tftp-server (under Ubuntu Linux) and check whether it is running:

sudo apt-get install tftpd-hpa service tftpd-hpa status

- Go to your work directory (/root/guruplug) and extract the u-boot and the kernel archive:

tar xvzf guruplug-u-boot-flipflip-20101111.tar.gz tar xjvf UImage_linux_kernel_2_6_33_7.tar.bz2

- Copy of the extracted contents the following two files to the folder where tftpboot resides, in my case /var/lib/tftpboot:

mv /root/guruplug/u-boot.kwb /var/lib/tftpboot mv /root/guruplug/uImage /var/lib/tftpboot

Part 2: The serial console / JTAG setup and ‘burning’ the images

- Connect via the serial console to the Guruplug, see this page. This
allows you to see what is going on on the device, including the boot process (U-boot).
- Turn on the Guruplug and see the device booting, when you see a message which allows you to interrupt the boot process by pressing a key, do so, this will show you the U-boot prompt
- Set some environment variables to prepare for ‘downloading’ the images from your TFTP-server (= serverip variable) to your Guruplug (= ipaddr variable). The IP addresses used here might be different for your network. The serverip is the computer running the TFTP-server. The ipaddr is the IP address you give to your Guruplug. It might be handy to save the environment variables so they are there everytime you boot.

setenv serverip=192.168.0.100 setenv ipaddr=192.168.0.110 saveenv

- Download the U-boot image from the TFTP-server into the memory of your Guruplug, erase the old U-boot image and write the new U-boot image into the memory of the plug. Finally reset the device. If everything went fine, you will see your updated U-boot prompt.

tftp 0x6400000 u-boot.kwb nand erase 0x00000000 0x0100000 nand write 0x6400000 0x0000000 0x80000 reset

- Now install the new kernel image from the TFTP-server into the memory of the Guruplug and set the environment variables and save them.

tftp 0x6400000 uImage nand erase 0x100000 0x400000 nand write.e 0x6400000 0x100000 0x400000

setenv x_bootcmd_kernel 'nand read.e 0x6400000 0x100000 0x400000' setenv x_bootargs_root 'ubi.mtd=2 root=ubi0:rootfs rootfstype=ubifs' setenv x_bootargs 'console=ttyS0,115200' setenv x_bootcmd '$(x_bootcmd_kernel); setenv bootargs $(x_bootargs) $(x_bootargs_root) ;bootm 0x6400000;' setenv bootcmd 'run x_bootcmd' saveenv

Now you should be able to boot up your Guruplug with a new U-boot and kernel installed by entering the following command:

reset

Useful links:
http://www.denx.de/wiki/bin/view/DULG/Manual
http://www.plugcomputer.org/plugwiki/index.php/U-Boot_Quick_Reference
http://www.plugcomputer.org/plugwiki/index.php/Re-building_the_kernel_and_U-Boot

Polder of Zuidland and Het Spui

Tjeerd — Sat, 11 Sep 2010 18:41:49 +0000

Last Monday I filmed nearby Zuidland and Het Spui. I used a tripod for a more stable underground. I experienced several issues which I need to solve, like the need for ND (neutral density/gradient) filters to minimalize the effect of over exposure of some footage. So I am now looking around for Cokin filtersets/adapters/holders which I can put on my lenses. Hopefully this improves the contrast/exposure effects.

Experimental footage of Castle De Haar, Haarzuilens

Tjeerd — Mon, 02 Aug 2010 13:45:19 +0000

Yesterday I went to castle De Haar in Haarzuilens to record some random locations with my camera and to test my monopod with my new wide-angle lens with polarisation filter. You will notice there is some shakey footage and even some moiree-effects on the castle walls. Actually it’s a relatively quick-and-dirty edited movie, but it’s a good way to learn and experiment with the camera. Remember: I have little to no knowledge about filming at all and that’s clearly visible, for now .

Pasture and nature between Haarzuilens and Vleuten

Tjeerd — Sat, 17 Jul 2010 19:29:27 +0000

Today I filmed in the grasslands between Vleuten and Haarzuilens with my Canon 550D-camera. It was nice weather with sun and clouds. This is actually the third or fourth time that I put some effort in filming and you can notice that in the experimental way it is done. Also I still need to find my tripod, because it is sometimes too shakey. But the image stabilizer of the Canon telelens does a good job to reduce the shaking.

Bollywood movies

Tjeerd — Sat, 15 May 2010 08:29:33 +0000

Will hollywood do a re-make of the following movie called Alluda Majaka with the actor Chiranjeevi? Never heard about both the movie and the actor, but a movie with ingredients like a flying tractor must be hilarious.

Photographing grasslands in Vleuten and Haarzuilens

Tjeerd — Sat, 08 May 2010 20:09:45 +0000

This week I finally made some time to take photographs of the grasslands between Vleuten and Haarzuilens. I had luck with the weather and I was just in time because when I came home, they mowed all dandelions. This is my first walk here with my new camera and it all seems to work fine.

You can see the pictures here .

New photocamera, Canon 550d

Tjeerd — Sat, 20 Mar 2010 20:24:13 +0000

A few weeks ago I heard about the new Canon 550D camera which was going to hit the market. This photocamera allows you to record movies in full HD resolution using your normal photography lenses. After seeing some recordings with this camera I was completely astonished by the filming quality. It looks so professional. I immediately ordered the camera and within a few days I received it. Unfortunately I don’t have that much time yet to experiment with it, but I managed to record from behind glass (at home) some hares in the pasture. But it is at 500 mm without a tripod, so it proves that it can record, but the quality is not representative.

Another issue is that my computer cannot manage to play the HD files, so I also need to buy a faster computer. Which probably will be required if I want to really start editing movies, my laptop is not fast enough.

Busy in our new house

Tjeerd — Sun, 15 Nov 2009 18:04:32 +0000

Not that I’m not writing anything at all at the moment, but since we got the keys of our new house two weeks ago, we are constantly busy with our new house. You can read updates about the work we are doing in our new house at our special website. If you want access to that site, please let me know.

2001: A Space Oddysey

Tjeerd — Wed, 21 Oct 2009 19:23:05 +0000

For years the movie 2001: A Space Oddysey was on my todo list, I watched it this evening. I’ve seen A Clockwork Orange – also from Kubrick - which was already vague, but this movie also has a sort of storyline which is really making it ‘complex’ actually. The focus is really on graphics and sound and some sort of story which is probably something for the viewer to think about.

What I dislike about modern day movies is that there is so much continuous action, overloaded with special effects, a lot of talking and not that much to think about. Then A Space Oddysey is a big contrast with that. Not bad to have seen it now finally.