Recently I have ordered a FT2232HQ mini-module from the webshop of Future Technology Devices Ltd. for use in an ongoing project with a Xilinx Spartan FPGA. In addition, I ordered a DLP-TH1b data acquisition module as a working application of a FTDI USB UART to play around with. Unfortunately, the source code for Linux systems on the website of DLP Design did not work at all. Opening the black sensor box revealed a Sensirion SHT11 humidity and temperature sensor. The source code has been changed a little using the datasheet of this device and the D2xx programmer’s guide of FTDI. My version is available for download using this link: dlp_th1b.tar.gz.

On request, the script to download and reconstruct TilePic images was modified for Windows users in a quick and dirty way. The requirements for using the script are installed versions of ImageMagick and wget for Windows. Place the following code in a text file, adjust the first two lines to point to the TilePic image and the locations of the installed programs, and change the extension of the filename to .bat to make it an executable script. The script will download all tiles with the highest resolution data. It can take several minutes to append all rows of tiles to make the final image, so be patient.
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Several sites are using the Tilepic image format to show sections of a larger image. The Tilepic file format contains the image data for a limited number of resolutions (levels) and all image parts (tiles) have the same dimensions. The first level contains the full image scaled to a single tile. The second level could contain 4 tiles of the same size, each containing a quarter of the image data at twice the resolution of the first level. The third level then contains 4 tiles for each tile of the second level, resulting in a total of 16 tiles for the full image. The advantage of the Tilepic format is that the client only needs to download the specific tiles for the shown part of the image from the level with the correct resolution. The websites usually provide zoom and scroll functions to magnify a part of the image.

Downloading the high-resolution image from the Tilepic file requires some knowledge on the location of the file on the server. This information can be found in the source code of the webpage and may for example be /photo/tilepic/image.tjp. The following script will download all tiles from all levels of the Tilepic image defined by $file.
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On April 21st 2006 I wrote: “Kids nagging for a pet animal are told they have to take care of the little critter themselves and that usually works for the first few weeks. At the same time, a lot of cat owners apparently already lost interest after reading the what-food-to-buy section in their operations manual. Why bother with litterboxes that have to be cleaned up … let the cat figure out where to crap. Having a better sense for decency (and knowing who feeds them), the cats don’t crap in their own garden but dig a hole in some other place … one of the corners of their territory and someone else’s garden. Cats are for comics and on National Geographic! New objective: defend garden and take offensive action against owners looking for missing cats.”

Since that post, I have managed to restrained myself from shooting cats and from taking a crap in someone’s garden. Instead, I have tried pepper, used coffee grinds and other eco-friendly plant extract chemicals. However, for some reason the cats in my neighborhood like their food spicy, are addicted to caffeine and have lost all sense of smell. Non of the so-called household solutions appeared to work here. Eventually I bought a battery-powered ultrasonic cat repelling device and this actually works like a charm. The cats even remind me when the battery needs to be replaced. Electronics to the rescue! Let me know if you have ideas on how to boost its power to include the other side of the house.

“This is a first shot: the start of hitting targets, which have not become fully clear yet. Trying to get used to the trigger threshold, the first shot is usually a miss. However, so is not taking the first shot at all. Slowly building up the pressure … waiting for the blind shot. Next, the aim will be under construction …” - 20050508.
“Waiting at an elevated hidden position, observing all activity, acquiring a target … and pulling the trigger. Not quite as smooth as it was supposed to be. After almost one year of being too busy to develop some simple weblog-thingamajing, I will start again by removing the failed attempt and thinking really hard on what this should become. To be continued … shortly!” - 20060419.

These two excerpts from old posts show it was not straightforward to maintain a weblog with just some ideas in mind, but without enough free time to collect the content for the posts. My objectives for this blog have changed in the past three years. I have made the decision to remove all previous posts and to start over. The amount of free time has improved and I should be able to find enough content from daily nuisances, ongoing projects and new experiences.