The setTimeout function allows you to delay the execution of code. The setTimeout function works by specifying a string of code followed by the delay in milliseconds. For example: setTimeout(“alert(‘timeout!’)”, 1000) The code above will display an alert box that says “timeout!” after 1 second (1000 milliseconds). Because setTimeout uses strings of text that it …
Category Archive: Uncategorized
Mar 24
How to create a git repository
How to create a git repository on your own server: mkdir <dir-name> chown <username>:<git-users-group> <dir-name> chmod g+ws <dir-name> cd <dir-name> git init chmod g+ws .git git config –bool core.bare true
Jun 12
How to create a MySQL database and user
How to create a MySQL database and user: create database <db_name>; create user ‘<user_name>’@’localhost’ identified by ‘<user_password>’; grant all on <db_name>.* to <user_name>;
Oct 22
Audio output selector
Using my headphones with my computer is frustrating. Whenever I want to use my headphones, I have to move my computer so I can access the back panel, unplug my computer speakers, and plug-in my headphones. Okay, maybe it isn’t that difficult, but it should be easier. How about a device that allows you to …
Sep 12
How to setup AVR projects
This brief tutorial demonstrates how to create projects for the AVR using AVR-GCC. This tutorial assumes that you are using Ubuntu for your development environment. This tutorial also assumes that you have already installed AVRDUDE. Also, you should have a development board with at least one button and one LED. In my case, the button …
Sep 12
How to use AVR Dragon
This brief tutorial demonstrates how to read, write, and erase an AVR chip using AVR Dragon. This tutorial assumes that you are using Ubuntu for your development environment. This tutorial also assumes that you have an AVR development board running a demo program. The JTAG port is used in this tutorial, but the ISP port …
Aug 30
Catalan numbers
Recently I was trying to count the number of n-bit numbers that have an equal number of 1′s and 0′s. For example, there are 6 such numbers for 4-bit long numbers (0011, 0101, 0110, 1001, 1010, 1100). I wrote a simple program to count such numbers for arbitrarily long numbers. However, the program was computationally …
Sep 03
How to make your own Arduino shield
After many months of working on my Arduino based project, I decided to finalize my project by making my own custom PCB. At first I wanted to design a PCB that connected to the Arduino through a series of cables. After some thought however, I realized that a shield would be better because it would …
Aug 25
Fun with FFT
This is a project that I threw together one weekend. The FFT is calculated using Processing. The FFT is then sent to the Freeduino via the serial port. The Freeduino displays the FFT on the dot matrix display using shift registers and a Darlington transistor array.
Jul 29
Improved light bar controller
I made several improvements to my light bar controller. I added a push button that pauses the controller on a desired color. I added a red LED to indicate if the controller is paused. I also modified the light bar so that it easily plugs into the breadboard. I did this by replacing the polarized …
Project Euler
