32-Bit AVR UC3 Microcontrollers, Atmel

AVR32 is a high-performance 32-bit RISC microprocessor core, designed for cost-sensitive embedded applications, with particular emphasis on low power consumption, high code density and high performance. The processor implements a Memory Protection Unit (MPU) and a fast and flexible interrupt controller for supporting modern operating systems and real-time operating systems. Higher computation capabilities are achievable using a rich set of DSP instructions.
To fully exploit the power of a 32-bit architecture, the AVR32 is not binary compatible with earlier AVR architectures. In order to achieve high code density, the instruction format is flexible providing both compact 16-bit and extended 32-bit instructions. While most instructions are 16-bit, powerful 32-bit instructions are implemented to further increase performance. Compact and extended instructions can be freely mixed in the instruction stream.

AVR32 Microcontrollers, Atmel