Generating Morse Code on the Raspberry Pi Using a Button on a Breadboard

Last time, I created a morse code generator. It took user input from the console, translated it into morse code, and blinked an LED to “transmit” the message. I decided to build on that a bit, adding a button to the circuit that allows me to generate morse code from a button click. The clicks are read in by a GPIO pin, and interpreted by a Python script. Defining the Rules We should always figure out what a program is going to do before we start writing it, so here are a few rules to guide us: Dots and dashes »

Using PullUp and PullDown Resistors on the Raspberry Pi

When you start out creating circuits with the Raspberry Pi and its GPIO pins, there’s an unexpected but important concept to understand, called “floating”. A Simple Circuit Imagine you’re creating a circuit using a breadboard. Something very simple… a button, some wire and a power source (like the 3.3v pin on the Pi). You just want to be able to click a button to complete the circuit. Maybe it looks something like this. The above circuit connects 3.3v, through a switch and 220Ω resistor, to pin #6. That won’t be very useful though, without a »

Building a Morse Code Transmitter on a Raspberry Pi

Last week, I made the Raspberry Pi blink an LED a few times. As thrilling as that was ;) I almost immediately wanted something more. Note: Source code for this project is available on GitHub. Goals Setup a simple circuit (LED and resistor) using a breadboard Learn about Morse Code in order to correctly translate a sentence Manipulate the GPIO pins on the Raspberry Pi to send signals at intervals Get familiar with basic Python constructs, like dictionaries, functions and loops Setup To do this, a few things are necessary: Install Raspbian on the Pi (comes with Python 3 preinstalled) Get »

Hello World for the Raspberry Pi (Making an LED Blink)

I finally unboxed my Pi a few weeks ago, and since then I’ve been learning some Python, which is the primary language of the Pi. You can do fun things with it out-of-the-box, like running and modifying the Python games that install with Raspbian (as well as writing your own), or playing around with MIT’s Scratch program (which also comes preinstalled). Or you could try another OS, like the OpenElec media platform that turns your Pi into a photo gallery / movie streamer (something a few of us were playing around with at the last AkronCodeClub meetup). But a »