Trinket and Gemma are perfect for small projects needing to receive some external event, triggering your own defined output. This project uses the Adafruit IR Sensor to first receive IR commands from a remote, then to use those codes in controlling a project of your own.
To learn about IR signals and how they are decoded by a microcontroller, see the IR Sensor Tutorial from which this tutorial is based.
Many larger Arduino projects use the excellent IRRemote library by Ken Shirriff. This library allows for multiple protocols and is quite flexible. But it relies on hardware specific to larger Arduino processors. This project simplifies the process of obtaining codes and using them to scale to the limits of the ATTiny85 processor in the Trinket and Gemma boards.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, or even use Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for MakeCode, CircuitPython, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.