http://www.crossstudio.co.uk/avr/index.htm

Professional Tools for AVR Developers
CrossWorks is the complete development solution for all your AVR projects―from initial design through final production, CrossWorks has it covered. Based on the successful work we have provided to OEM customers, our offering continues to move from strength to strength.

CrossWorks for AVR sets the standard for AVR development tools. The toolset provides a complete and cost-effective solution for programming the AVR family of low-power microcontrollers. CrossWorks supports all megaAVR controllers in the AVR family, from the smallest to the largest. We bundle an ANSI C compiler, macro assembler, linker/locator, libraries, core simulator, flash downloader, JTAG debugger, and our class-leading integrated development environment, CrossStudio.

Our C compiler is the benchmark for code quality and performance for the AVR microcontroller. Compliant to ANSI and ISO standards, professional and robust, it's the perfect choice for any AVR project. Coupled with our CrossStudio development environment, it makes an unbeatable development tool!

Processor Support
megaAVRs

ATmega48, ATmega8, ATmega8L, ATmega88, ATmega8515, ATmega8515L, ATmega8535, ATmega8535L, ATmega16, ATmega16L, ATmega162, ATmega162V, ATmega165, ATmega165V, ATmega168, ATmega32, ATmega32L, ATmega325, ATmega3250, ATmega64, ATmega64L, ATmega640, ATmega645, ATmega6450, ATmega128, ATmega128L, ATmega1280, ATmega1281, ATmega2560, ATmega2561
tinyAVRs

ATtiny13, ATtiny2313, ATtiny25, ATtiny45, ATtiny85
LCD AVRs

ATmega169, ATmega169V, ATmega329, ATmega3290, ATmega649, ATmega6490
Smart Battery AVRs

ATmega406
Lighting AVRs

AT90PWM2, AT90PWM3
CAN AVRs

AT90CAN128


Processor Support ― assembler only
tinyAVRs

ATtiny11, ATtiny12, ATtiny15L, ATtiny28L