Arduino++
App Inventor (AI2) is an easy way to create Android apps. While originally designed for teaching, it still allows building advanced and complex apps, and was the tool I chose to build a software 2-axis joystick interface for wireless vehicle control.
This article describes the implementation of the joystick as a standalone component that can be integrated into other applications.
When you need to process an interrupt, there is nothing else you can do but process it. Most Arduino examples show how to do this in a ‘C’ context. Processing interrupts in a C++ class is a lot less trivial, as class scoping rules and constructs get in the way, and specific arrangements need to be taken to ensure data is processed correctly.
Menu managers in embedded systems are generally not the main function of the embedded application software, but they can take considerable code and testing to implement.
This article describes a menu library that minimizes the use of RAM and has a small memory footprint overall, leaving more space for what really matters in application code.
A Servo Tester is a useful addition to any Maker’s toolbox, especially if they need to work with servos. I have always ‘made do’ when setting up servos by setting up an Arduino and modifying the standard examples to do what I needed at the time (setting the mid point, calibrating for servo swing, etc).
I finally decided that I needed a more permanent tool and made my own.
When I needed a high brightness 7-segment display and discovered that I did not have one at hand, I turned to an available Neopixel (WS8212B) 10×10 matrix to act as temporary display. This turned out to work well enough that it could be used in other situations.
Having acquired a FlySky 6 channel Radio Control transmitter (FS-T6) for a planned model airplane, I decided to take on the common advice that it is worth practicing on a simulator before being let loose on the ‘real thing’. Here’s what’s required.
When planning a new project I needed to tackle how to remote trigger a Canon DSLR camera. So I started with looking at the options and landed on using an infrared link to the camera. Things didn’t quite go as I expected.
Of all the many questions that have been asked about issues they face when using the MD_Parola and MD_MAX72XX libraries, there are a few themes that keep re-emerging. In this article I’ll cover the top eight questions, their most likely cause and solution.
It is common for operating systems to use a hard disk swap files to increase the amount of available system RAM by swapping blocks(or pages) of memory between real RAM and the hard drive. As many applications use RAM linearly, this imposes relatively modest decrease in performance for the bigger benefit of increased temporary RAM.
It seemed to me that, for particular applications, this concept could be applicable to providing management of arrays to increase what could be stored in a microcontroller’s very limited memory resources.
Sometimes it’s fun to do things just because they are interesting. This idea seems to be behind minimalist programming languages (languages with barely enough keywords to be viable). These languages have no useful purpose except to pose a challenge to programmers using them. Here’s one I played with on the Arduino.
