I used the piece of code to print a line to a matrix printer from PostgreSQL. The matrix printer was connected to the database server and supplied with endless paper. I used a matrix printer, because you can print directly to the device.

With the method, described below, it’s possible to print with a SQL query or print something initiated by a trigger. Using this method you can log specific data ‘offline’.

The print_line method consists of three files; print_line.c which contains the code to address the printer, a Makefile to compile the print_line.c file and a print_line.sql file which creates the function in SQL.

print_line.c

Makefile
MODULES = printhash
PGXS := $(shell pg_config --pgxs)
include $(PGXS)

print_line.sql
CREATE FUNCTION print_line(text) RETURNS integer
AS '/usr/local/libexec/print_line.so', 'print_line'
LANGUAGE C STRICT;

Installation:
mkdir /home/user/print_line
cd /home/user/print_line
unzip print_line.zip
make
cp print_line.so /usr/local/libexec/
// open postgresql command line client and execute:
# \i /home/user/print_line/print_line.sql

Usage:
SELECT print_line('Hello World!');

Download:
Download print_line.zip

“Verder spraken we voor deze editie met de ontwikkelaar van Diversia, een open source-variant op Second Life. Waarom Diversia wel een succes wordt, terwijl Second Life langzaam verandert in een spookstad, legt projectleider Melvin Rook uit in een rijk geïllustreerd artikel.”

Inmiddels heb ik ook al veel positieve en leuke reacties op het artikel ontvangen.

More information on Synology NAS systems can be found at www.synology.com

On my workstation Google supplied their new design to me. I didn’t really liked this new design at first and that feeling became worse when I noticed some bugs. Also, the new design feels slower than before.

The first picture shows a flaw in the text field. ‘Taller’ letters will be cut at the bottom:

The second picture shows a more serious bug. Typing a search phrase and pressing enter results in the page with results and the suggestion dropdown from the previous page still visible.

I have tried to file a bug report, but it seems impossible to contact them directly.

Would like to try the new Google interface? Perform the following steps to make it so:

• Visit Google
• Clear out the contents in your address bar
• Enter the following: javascript:void(document.cookie=”PREF=ID=20b6e4c2f44943bb:U=4bf292d46faad806:TM=1249677602:LM=1257919388:S=odm0Ys-53ZueXfZG;path=/; domain=.google.com”);
• Press the Enter key

Packages

Download and install the following packages and it’s dependencies:

• Code::Blocks
• libwxgtku2.8
• libwxgtku2.8-devel
• wxGTK2.8

wxFormBuilder

Download the wxFormBuilder 3.0 linux source including the pre-generated Makefiles. Now unpack the tarball, build and install wxFormBuilder:

• cd /usr/local/src/
• wget or fetch wxformbuilder-3.0.57.tar.gz
• tar -zxvf wxformbuilder-3.0.57.tar.gz
• cd wxformbuilder_3.0.57
• make CONFIG=Release
• ./install/linux/wxfb_export.sh /usr

Code::Blocks

• Start Code::Blocks and open the menu Tools -> Configure tools…
• Click on Add.
• The following picture shows how to setup the tool:

• Save the settings and open the menu File -> New -> Project
• Choose wxWidgets project
• Walk trough the wizard
• Use wxWidgets 2.8.x
• Preferred GUI Builder: wxFormBuilder
• Application type: Frame Based
• Use the default widgets configuration

When you would like to modify your GUI you can open the following menu: Tools -> wxFB. Which will launch wxFormBuilder with your GUI. When it asks for conversion, click yes.

Don’t forget to generate the code (press F8) before you switch back to Code::Blocks. Otherwise you changes won’t be visible. You also need to build your project in Code::Blocks before your changes are visible.

In certain versions and combinations of the software the following compile error could occur: “wxMessageBox was not declared in this scope”. There are two solutions to this problem:

1) I noticed wxFormBuilder changed a bit. All headers where included in the generated code, even when the headers were not necessary. Now not all the headers are included. When you use other wxWidgets methods just add the proper header. In this case you can use the following include:

#include <wx/msgdlg.h>

2) Do not use the Code::Blocks wxWidgets template and just setup a clean C::B project. Then also setup a clean wxFormBuilder project by using the inherited class tutorial (*). Finally add the code manually to the project.

Links

• Code::Blocks
• wxFormBuilder
• Inherited class tutorial (*)

The sign, which read “Raptors Ahead Caution,” amused motorists in a construction zone on Keystone Avenue, just north of 116th Street.

“It’s kind of crazy. I’m totally confused,” said one motorist. “I’m kind of expecting … dinosaurs to run down the road, or something.”

Another puzzled motorist said, “Which raptors?” before adding that he hadn’t seen the sign.

Carmel spokeswoman Nancy Heck said the signs on Keystone Avenue are owned by a contractor, Highway Technologies, which is responsible for programming signs in the Keystone Avenue construction zone.

The odd road sign in Indiana came days after a widely publicized highway road sign message near the University of Texas that warned motorists “Caution! Zombies Ahead!” and “Nazi Zombies! Run!!!”

Another sign in Collinsville said: “Daily lane closures due to zombies“.

Apparently, while most road sign control pads are placed in a lock box, that box is rarely actually locked. And while most road signs are under password protection, that password is most generally just the default code “DOTS”—or you can easily reset the password by holding “shift” and “control” while typing “DIPY” (so that it just defaults to “DOTS” again).

Of course, these actions are illegal, so play around with it at your own risk.

In speaking of the sign “hackers ahead”, don’t forget the hacker event ahead: Hackin at Random in august 2009: www.har2009.org!

The TMP421, TMP422 and TMP423 are the industry’s smallest remote junction temperature sensors with a built-in local temperature sensor. The single remote channel TMP421, dual remote channel TMP422 and triple remote channel TMP423 provide a remote sensor accuracy of +/-1C (maximum) and a local temperature sensor range of +/-1.5C (maximum). Both sensors are RoHS compliant and can be used in numerous applications including LCD/DLP®/LCOS projectors, servers, central office telecom equipment, and laptop computers. They are also suitable for industrial controllers, processor/FPGA temperature monitoring and storage area networks.

The TMP421, TMP422 and TMP423 feature a two-wire/SMBus serial interface as well as multiple addresses. The remote temperature sensor diode-connected transistors are typically low-cost NPN- or PNP-type transistors or diodes that are an integral part of microprocessors, microcontrollers and FPGAs. The TMP421, TMP422 and TMP423 also include series resistance cancellation, programmable non-ideality factor and diode fault detection.

The sensors operate on a standard I2C/SMBus compatible, two-wire interface over a temperature range of -40°C to 125°C, with a remote temperature range of up to 150C. For maximum power savings, the device circuitry (other than the serial interface) can be shut down, thereby reducing current consumption to typically less than 3uA.

More information can be found on the following URL: http://www.ti.com/tmp421-pr

Driver pre-release download (no warranties!): tmp421-src.tar.gz

In the summer of 2003 I build this solar powered mini car with a friend as a school project:

Specifications

Weight: 200 grams
Length: 260 mm
Width: 120 mm
Average speed: 0,051 m/s (0.18 km/h)

Parts used

-Body made of balsa wood

-A few Meccano pieces

-Wheels
Two rear wheels
One front wheel

-Solar panels, 4 pieces:
Net voltage 0,55 – 0,6 V
Short-circuit current 650 mA
Size. (lxb) 50 x 50mm.

-Motor, designed for solar panels:
Net voltage 0,4 V/10 mA
Size. (Æxh) 35,4 x 26 mm · Axis-Æ 2 mm
Suitable for use with solar panels with a return of more than 10 mA.

-Crocodile clips, 4 pieces

-Wires, lot’s of wires

-(Hot) glue

-A rubber band

Building the car

We started with (hot)glueing the body of balsa wood together.

The solar panels are put on a bigger panel and are connected in parallel. The solar panels are connected with crocodile clips and will be wired to the engine. As you can see in the pictures, I broke one of the panels. Oops.. They are very fragile… Though, the most interesting was that it still worked.

We demolished some old toys and as a result we had a nice set of wheels. For the rear we used a nice pair of wheels which already were connected with an axis. The front wheel came from some other toy. With the help of some Meccano elements the wheels were mounted to the body.

The motor is placed in a special engine compartment. We used a rubber band to transmit the power from the engine to the wheels.

Testing the car

In the begin of the progress we tested the motor and the solar panels under a halogen light. Later on, in an outside test the cars’ average speed was 0,051 m/s (0.18 km/h). The tests can be viewed in the video at the bottom of this post.

Video