I’m working on a little timekeeper project that works similarly to those word clocks, but it will be wrist-mounted. I have to make this little guy tiny, so I’m going with all SMD and to light the 21 LEDs, I’m using a 5-pin Charlieplexing scheme. To give back to the community (and FWIW), I am writing up my understanding of and methods for implementing Charlieplexing on an Atmel ATmega328 AVR (or Arduino). This first part of the 2-part series goes over the concept of Charlieplexing. The second article will show my homemade quality control methods and Arduino and AVR C code. I hope someone finds the write-up useful!
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.