Add Rotary Control to Your PC with Adafruit's Keychain-Sized Rotary Trinkey

A SAM D21-based board fits into a USB port. One side has an encoder and the other has a NeoPlxel.

James Lewis
3 years agoProductivity

Adafruit adds another USB-port trinket to consider for your customized computing needs. The Rotary Trinkey is a keychain-sized SAM D21-based board that plugs directly into a USB port. On one side of the PCB is a rotary encoder and on the other is an RGB NeoPixel.

"It’s half USB Key, half Adafruit Trinket, half rotary encoder… it’s Rotary Trinkey, the circuit board with a Trinket M0 heart, a NeoPixel glow, and a rotary encoder body."

Previously we covered Adafruit's Neo Trinkey, which featured 4 RGB LEDs and two capacitive touch buttons. This iteration of Trinkey adds a space to solder a rotary encoder provided by you.

Unlike potentiometers, rotary encoders continuously spin. Instead of changing resistance, capacitance, or inductance, they generate pulses as they turn. A microcontroller can monitor these pulses to determine both how much the knob has twisted and in which direction.

On the Adafruit Rotary Trinkey is an RGB NeoPixel LED. NeoPixels are an LED package containing three elements (red, green, and blue) and a shift register. The shift register makes them fully addressable. But, in a design like this one, they work fine even when there is only one!

Rotary Trinkey uses the Microchip SAM D21 32-bit Arm Cortex-M0+ microcontroller. One of its many features is native USB support. This support means you can emulate a wide range of USB devices. For example, Rotary Trinkey could appear as a USB Mouse where the encoder acts like the mouse scroll wheel. You can easily program the board with either the Arduino IDE or Adafruit's CircuitPython.

The Trinkey DOES NOT come with a rotary encoder knob. You must add and solder one yourself. The Rotary Trinkey is now available for $6.95 on Adafruit.

James Lewis
Fan of making things that blink, fly, or beep. Host on element14 Presents, baldengineer.com, AddOhms, and KN6FGY.
Latest articles
Sponsored articles
Related articles
Latest articles
Read more
Related articles