ATMEL Atmel AVR micro controller ATmega48P/V ATmega88P/V ATmega168P/V ATmega328P Preliminary handbook

ATmega48P/88P/168P/328P is a high-performance, low-power AVR® 8-bit microcontroller from Atmel. It features an advanced RISC architecture, 131 powerful instructions, most single-cycle execution, 32 x 8 general-purpose working registers, fully static operation, up to 20 MIPS throughput at 20 MHz, and an on-chip 2-cycle multiplier.