MonthDecember 2010

Diagnosing the Source of Internet Connectivity Problems

I created a nice little flowchart for people to diagnose their Internet connectivity problems.  It’s pretty general and covers the most common problems.  I tried to avoid lots of specific information since many Internet connectivity problems are not as straightforward as just following a flowchart.

I didn’t really go into specifics as to what kind of modem lights to look for because all modems are different.  But they almost always will have an “Online” light.  If that is off, then there is clearly a problem.

Router lights are usually just a power light, the WAN and LAN lights.  If the WAN light is off, it means the router has no access to the Internet.

Each network adapter on the computer can be disabled and enabled by accessing “Network Connections” in Windows.  That can be accessed by typing the name without the quotes in the address bar in any open Explorer window.

Axis and Allies 1940 Battle Calculator/Simulator Updated to v1.0

No big changes really, other than the fact that there is now a button for swapping attacker and defender so that people can see how the odds changed if the roles were reversed.

For more information about the program, see the original post about it.

Requires Java to be installed.  Link for that here.

SourceForge Page:


Source Code:

Heboris UE Devil Minus Completed!

After a bit of trying, I finally completed Devil Minus on Heboris!  Heboris probably the best Tetris game out there as it most closely matches those Japanese Tetris arcade games.

Family Gatherings During Christmas

This is just a thought that I had.  It seems to me that from childhood, we are taught that Christmas is a time for family to get together and celebrate the holidays.  I found that on Christmas Day, a lot of people that I knew stayed home and spent time with their family rather than hanging out with friends.  This is true to what I just mentioned earlier, but at the same time, it seems that people would rather hang out with their friends instead, and that staying home with family is obligatory.  Just an observation.

Installing RXTX for Serial Communication with Java

Java supports communication to serial ports, but not with its default installation.  It requires an installation of an external library.  Currently, two options exist for achieving serial communication:

Unfortunately, the current version of JavaComm does not support Windows, and only supports Solaris SPARC, Solaris x86, and Linux x86.  Since I use none of those operating systems, this article will only discuss how to install RXTX in Windows.

UPDATE: 12 Sept 2011 – Thanks to a comment from Kurt Zoglmann, there are instructions on how to do this with a Mac!  I never tried this myself because I don’t have a Mac, but the procedures stated there look good to me (see comments).

A 32 and 64 bit version of the library exists.   I’ve updated this article from when it was first published to include the new locations for where to download the libraries, but I have not gone through the installation of the libraries again, so I’m not surprised if the rest of the content on this page is outdated too.

32-bit version:
64-bit version:

To install the libraries (instructions from JControl):

    1. Copy rxtxSerial.dll to %JAVA_HOME%bin, (%JAVA_HOME% is the folder where JRE is installed on your system; e.g. c:Program FilesJavaj2re1.4.1_01)
    2. Copy RXTXcomm.jar to %JAVA_HOME%libext

Once installed, the IDE will need to know where to look for these installed files.  Even though the files exist in the JRE directory, each project needs to know about these files.  More information on this website.

In order to start coding with this library, import*.  For more information about Java Serial Programming, look here.

Happy coding!

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