ATMEL ATmega128 ATmega128L Summary Manual

This product is a high-performance, low-power AVR® 8-bit microcontroller that uses an advanced RISC architecture with 133 powerful instructions, most of which execute in a single clock cycle. It has 32 8-bit general-purpose working registers and peripheral control registers, fully static operation, and up to 16 MIPS throughput at 16 MHz. It also has an on-chip 2-cycle multiplier.