On past projects, when I needed multiple LEDs, I just connected each to its own GPIO pin. I knew the current only worked in one direction, but I didn't think to take advantage of that fact. Charlieplexing is a method for arranging multiple LEDs so as to use the minimal number of pins possible.
One of the coolest things about the Raspberry Pi is its GPIO pins. They’re just sitting there, waiting to be connected to all kinds of useful peripherals so your Pi can interact with the world around it. Power an LED to signal the user. Place a button in the
After getting PWM (pulse-width modulation) to work with an RGB LED last week, I was trying to think of what else I could do with an LED that demonstrated changes in color as well as intensity. I’m not sure why – maybe it was because we lost power in our
If you buy a kit with random LEDs, wires, switches, etc, you’re likely to end up with one or two of those funky little LEDs that appears to be white, and has 4 wires instead of 2. I had set mine aside and made a mental note to figure
Have you been around long enough to remember the popular Simon game from the 70s and 80s? There’ve been plenty of remakes over the years, but I had one of the originals when I was younger. It’s a game of patterns that tests your memory. It flashes a
After seeing Scott Fradkin live-code Sonic Pi for nearly an hour at Stir Trek - not only explaining what it was capable of but showing us too - it inspired me to do a little experimenting of my own once I got back home.
What a indicator light when you get new email? Here's how to flash an LED on your Raspberry Pi when someone sends you a message!