Archive for the ‘Coding’ Category.
A while back, I created an Arduino plugin for NetBeans so that I could use the full-fledged NetBeans IDE for all my Arduino projects. The approach I took was using the NetBeans project sample module method. Under the hood though, it is nothing more than a makefile and an source file template. Continue reading ‘Makefile for Arduino 1.0’ »
Alexa is a great tool for gathering your website’s statistics. Using its traffic rank moving average, you can see how your content affects your site’s popularity over time. Continue reading ‘Simple Alexa Ranking Script’ »
DS28EC20 is a 20Kb 1-Wire EEPROM chip from Maxim. Like all other 1-wire devices, only a single pin is needed for both power and communication. In this blog posting, I will show you how to how to communicate with DS28EC20 using the popular Arduino platform. Continue reading ‘Interfacing DS28EC20 with Arduino’ »
When working with micro-controller projects, it is often necessary to perform calculations in binary and hexadecimal forms. While almost all calculator tools (such as calc under Windows and gcalctool in Linux) can handle such tasks, they are designed for general purpose calculations and not geared specifically towards working with digital circuits. Continue reading ‘Hex/Bin/Dec Converter And Calculator’ »
One of my recent projects was to build a POV display device. There are already many microcontroller based POV devices out there, but most of those I have seen use around eight LEDs and have fixed font types. So I thought of developing something that is larger (e.g. using more LEDs) and more flexible (e.g. can display both text and images). Continue reading ‘POV And POV Image Encoder’ »
I was inspired by Paul’s 7 segment display and decided to build one myself. He used 4 common cathode 7 segment displays. In his original schematics, all the segments within a display shared one current limiting resistor which unfortunately affect the display brightness when different numbers of segments are lit. I happened to have two common anode dual 7 segment displays (QDSP-G545) so I decided to use them and four 74HC595 shift registers to build a four 7-seg display. Realizing that other people might be using either common anode or common cathode displays, I also built a library that can be used for either case. Continue reading ‘4 Digit 7 Segment Display Using Arduino’ »
Sometimes a group of concurrently running threads may need to rendezvous at a certain point in time before they can further proceed. This situation commonly arises in areas like event simulation, where the events are synchronized via a clock event (see illustration below): Continue reading ‘A Simple Thread Barrier Implementation’ »
A palindromic prime (palprime) is a prime number that is also palindromic. So out of curiosity I wrote a simple program a few days ago that can find the palindromic numbers within a given range. Here is the code in C++: Continue reading ‘A Simple Program for Finding Palindromic Prime Numbers’ »
Even though multi-core processors are almost ubiquitous nowadays, applications are slow to catch up. Of course, one could always re-write the applications in order to take the full advantages in a multi-core environment. But it is not an easy undertaking. Continue reading ‘Poor Man’s Parallel Task Dispatcher’ »
I was trying to search for some code examples on how to do a recursive directory search under Linux using C++ the other day. But to my surprise, I could not find any place that offers a complete example. So I decided to post my code here after I created my own and hopefully you will find it helpful. Continue reading ‘C++ Recursive Directory Search Under Linux’ »
As I wrote last time, I did a clean Ubuntu 9.04 install on my main PC. Continue reading ‘Magick++ Missing Delegate Error’ »
In the example I gave in “Interfacing IPP with Magick++“, I illustrated how to use Intel’s Integrated Performance Primitives (IPP) to perform edge detection. One issue with Canny edge detection algorithm is that we need to specify a high threshold and a low threshold. How to select those threshold values affect the quality of the detected edge greatly. And in my previous example, the threshold values were chosen manually. In this blog post, I will examine a couple of simple methods that can be used to automatically determine the threshold values. Continue reading ‘Canny Edge Detection Auto Thresholding’ »
So far I have been mainly using KDevelop and Code::Blocks as my C++ development IDEs. Recently, I started using NetBeans IDE for C++ and I started to like it quite a bit. Continue reading ‘C++ IDEs Under Linux’ »
A couple of weeks ago, I wrote about how to interface Integrated Performance Primitives (IPP) with Magick++. While IPP offers excellent performance advantages, it does not come with the easiest programming model. Fortunately, it is easy enough to create a C++ wrapper on top of IPP and provide an easier to use programming interface. Continue reading ‘An Image Class Based On IPP’ »
Intel’s Integrated Performance Primitives (IPP) is a low level C++ library. It provides routines that are highly optimized on Intel processors. I recently started using it because its vast speed advantage in signal and image processing applications. Continue reading ‘Interfacing IPP with Magick++’ »