How to Install an ATtiny Bootloader With Virtual USB
Contributors:
Shawn Hymel
Shawn Hymel 
Resources and Going Further
While this is a lot of information to take in, it shows how to hack the Arduino IDE to load custom board definitions. These steps should work for other ATtiny devices that are supported by the micronucleus project, such as:
You might have to modify the pins_arduino.h file, however, if you plan to use a different ATtiny.
ATtiny84 Pinout
If you need additional support, please check out the following resources.
If you want to go further with the ATtiny, please check out our additional tutorials that showcase the ATtiny:
Electronic E-craft Terrarium
A guest tutorial on an Electronic Terrarium from the Performative Sculpture class of Parsons DT.
Qwiic Single Relay Hookup Guide
Get started switching those higher power loads around with the Qwiic Single Relay.
Qwiic Joystick Hookup Guide
Looking for an easy way to implement a joystick to your next Arduino or Raspberry Pi project? This hookup guide will walk you through using the Qwiic Joystick with the Arduino IDE on a RedBoard Qwiic and in Python on a Raspberry Pi.
SparkFun Qwiic Button Hookup Guide
A Hookup Guide for the SparkFun Qwiic Button (Red) and SparkFun Qwiic Button Breakout. Goes over connecting the Qwiic Button to an Arduino microcontroller and using it with the Qwiic Button Arduino library.