Secret Code
Build a secret message encoder with Morse code.
Building a secret message encoder
Lead Image © kudryashka, 123RF.com
In this issue, I'll show you how to use the Scratch list feature to build a message encoder (or translator) that can be played back using a simple circuit on the GPIO. From a programming skills perspective, it will demonstrate how to manipulate the individual characters of much larger strings and transform them into something new.
I remember creating codes with my friends so that we could write "secret" notes to each other in school. Sometimes, the code used simple substitution (e.g., Z for A, Y for B, etc.), and other times the code was gibberish. In this project, I'm going to show you how to build your own message encoder using Scratch to substitute letters and numbers for Morse code.
Even though the project can ultimately be used to encode messages based on any rules you might want to make up, I'm going to demonstrate it with Morse code. Morse code, although it has many historical uses, including amateur radio, aviation, and of course the emergency signal SOS, is not encountered too often by the public.
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