boards-manager topic
atmega
Bare ATmega 8/168/328 microcontrollers with the Arduino IDE.
MajorCore
An Arduino hardware package for ATmega8515 and ATmega162
MegaCore
Arduino hardware package for ATmega64, ATmega128, ATmega165, ATmega169, ATmega325, ATmega329, ATmega640, ATmega645, ATmega649, ATmega1280, ATmega1281, ATmega2560, ATmega2561, ATmega3250, ATmega3290, A...
MicroCore
A light-weight Arduino hardware package for ATtiny13
Arduino_Boards
Board definitions for SparkFun-manufactured AVR, ARM, and ESP-based Arduino boards.
TI_Platform_Cores_For_Arduino
Replace Energia with Arduino. Use the Arduino IDE or CLI with Texas Instruments processors in the MSP430, MSP432, and Tiva families using the Arduino Boards Manager.
Arduino_Boards_Index
Electronic Cats Package Lists for the Arduino Board Manager