The Teensy 4.0 and 4.1 microcontrollers are a game changer. They’re a quantum leap in CPU speed and processing power. My first thought was what kind of program could use this level of performance and Mandelbrot images came to mind -- a favorite programming pastime of mine. Here’s how it went.
After creating an Internet connected digital clock using the Adafruit RA8875 driving an seven inch LCD display, I decided to step it up a notch and add several additional features including: the ability to set an alarm; a countdown timer for uses like monitoring an exercise program; a weather display to provide brief conditions at 10 different cities; a real time stock market report that gives the changing prices for a selection of stocks; and lastly (just for fun), a Mandelbrot fractal generator to produce those wonderful images.
The February and March 2018 editions of Nuts & Volts featured my article detailing the Arduino Graphics Interface (AGI) project which described a general-purpose hardware and software platform that could draw graphical objects onto the face of any analog oscilloscope. A reader challenged me to see if the AGI concept and software library could be ported to the newer and faster TEENSY 3.6 processor. This article describes the new and improved TEENSY Graphics Interface project that implements a fully operational “CRT Clock” as a working demonstration of a TEENSY based graphics platform.
Typically, one of the first experiments people do when working with microcontrollers is to blink an LED. However, the thrill of this wears out pretty quickly, so let’s see what else can be done.