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!

Axis and Allies 1940 Battle Calculator/Simulator

Here’s a program I made for calculating the odds for battles in Axis and Allies 1940 (download link at the bottom).  Making this program was largely motivated by the lack of a battle calculator for this version.  This program is also released under the GPL.


  • Land and naval battles
  • Coastal bombardments from Cruisers and Battleships
  • Option for ground units that must survive to capture the territory
  • Option for aircraft that must land on an Aircraft Carrier
  • User specifiable option for how many trials to do
  • Follows combat rules from Axis and Allies 1940 (Europe and Pacific) such as:
    • Regular land battle rules (dice rolling)
    • Order of taking casualties
    • Submarine first strike and can be negated by Destroyer
    • Planes cannot hit Submarines unless the planes are accompanied by a Destroyer
    • Artillery-supported Infantry and Mechanized Infantry
    • Fighter-supported Tactical Bombers
    • Wounds on Battleships and Aircraft Carriers
  • Statistics for:
    • Attacker/defender win/loss/tie percentages
    • IPC cost of both armies
    • IPC loss of both armies
    • Units remaining of both armies


Requires Java to be installed.  Link for that here.

SourceForge Page:


Source Code:

How Long Stuff Takes to Get Used Up

Kind of random, but I thought I’d make a list of how long these common household items take to get used up.  These are pretty much estimates that are just based on my own usage habits.

Item Time to Consume (months)
Bar of Soap (1” x 3” x 4” approx.) 2.5 – 3
Bottle of Shampoo (355 mL) 3
Toothpaste (170 mL) 5

Hmm so taking the lifetimes of all these items, the lowest common factor is 15.  For every 3 tubes of toothpaste, I should buy 5 bars of soap and 5 bottles of shampoo.  Assuming that I start using all of these at the same time that is.

Looking at these numbers puts things into perspective.  I always felt like I’ve been replacing these same items over and over, but I guess I just lost track of how long it had already been since I last replaced it.

Total Pages in a Report VS Number of Authors

The topic of laboratory/school reports came up during a conversation with a friend.  It is obvious that as the people in a group increases, the total pages in the report will increase.  But the question is… by how much?

I thought back to the work that I did and came up with this:

It appears that there is a linear relationship here.  Pretty good R squared value too.

This is quite nerdy…but who cares?

Removing Random Lag on Windows Live Messenger 2009

Every now and then I’d notice some lag every time I used MSN.  I had no idea, but after some Googling, I found the culprit.  It happened quite randomly so I couldn’t really tell why it happened.  Link to the solution below.


Enabling Links on Windows Live Messenger 2009

Some time ago, Microsoft disabled clickable links within Windows Live Messenger 2009.  Since they were able to remotely disable this for all users, there must be an identifier within the program that governs this. The solution to getting links back on WLM 2009 is to use a hex editor to edit the exe file to allow hotlinks again.  More info in the link below. 


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