Tutorials

Coding conventions and code quality are practices of programming that are often ignored by many of us software developers. However when working on a school project with 6 other peers, I was responsible for setting up a program called SonarQube to analyze the quality of our code. Not only did SonarQube detect multiple quality issues with our code base, it also provided many useful suggestions to improve code readability, increase robustness against bugs, and every prevent security risks. The following blog post is based off of an e-mail that I wrote to the team explaining many common software quality issues that were arising in our code along with suggestions on how we could improve. I find that many of these tips can be applied to any JavaScript project and I am personally always taking them into account when I program web applications.

The various transport agencies in Quebec have been using the OPUS card for contactless fare verification. Seven years after it was released, OPUS en ligne has now been introduced and allows the purchasing of fares online through a card reader connected to your computer. I decided to get one of these required $14.49 readers and give it a spin. Does it work? Is it a trip into the technological Stone Age or will it revolutionize the way we purchase bus passes? Join me on this journey to find out!

This project started off when trying to find a use for a broken laptop. The screen was perfectly fine so I decided to integrate it with a Raspberry Pi. The Raspberry Pi is a fascinating computer great for small multimedia projects. I had such a project in mind, but first I wanted to test out the Pi to see what it was capable of so I create a test bench. The arrangement was fairly simple with the Raspberry Pi, a laptop LCD display, and a LCD controller to connect the two together. This setup was a great way to tryout the Pi and to recycle an old computer into a new one.

A project I was working on a while ago encountered a problem when we decided to use multiple I2C color sensors. The I2C protocol relies on the fact that each device you connect as a unique address. But in the case of the sensors we were using, the address is hard wired into the device, so connecting multiple identical sensors with the same permanent address would creating a conflict. This problem was easily solved with the use of an I2C multiplexer. Not much information was available on the web regarding this solution, but after doing some research we learned that the implementation is very easy. Read on pass the break to see what we learned and how you can use multiple identical I2C devices in your Arduino projects.

One of the great things I learned working on my previous project, the AEMD Alpha, was using the Arduino to control an LED matrix. The Adafruit libraries for the device took care of the multiplexing and other complexities and all that was left was controlling the individual LEDs from their x and y coordinates. But this led to the next challenge of how exactly to get images and graphics on the Arduino. First I'll describe a logic solution, but I'll show how this method falls apart. The alternative solution requires arrays of bytes (or integers) which is where my previous post introducing Bytety comes in. This little web app that I created presents a mock matrix that you can play around with to create your own graphics, and the program generates the necessary array for your Arduino code. Continue reading on to learn my easy solution to display images on a LED matrix with an Arduino all while improving the memory footprint of your program.

Let's start off with something a little different that has nothing to do with the programming or technology that I'm used to. All of us have encountered the dreadful spaghetti of wires while charging our devices. I've seen many people's solutions to taming the situation on the web and thought I'd try my own take to the problem. Continue reading and join me as I tread for the first time into the art of woodworking.