AVR 8-bit Microcontrollers from Microchip
ATtiny and ATmega AVR 8-bit microcontrollers from Microchip (formerly from Atmel).
ATtiny Parametric Table
Microchip Studio is an Integrated Development Environment (IDE) for developing and debugging AVR and SAM microcontroller programs written in C, C++ and assembly language.
Downloads Archive for AVR and SAM MCUs/MPUs
The Microchip downloads archive contains older versions of Atmel Studio, AVR Studio, AVR and Arm-Based MCU/MPU Toolchains for Windows and Linux, and Advanced Software Framework (ASF) packages.