The ATmega644PA produces throughputs close to 1MIPS per MHz, by using up to 131 powerful instructions in a single clock cycle. Using this process, the designer can optimize the ATmega644PA for power consumption versus processing speed. The 32x8 general-purpose working registers with an extensive instruction set are combined in the Atmel AVR® core.
The 32 general-purpose working registers are directly connected to the Arithmetic Logic Unit (ALU). This allows two independent registers to be accessed in a single instruction and executed in one clock cycle to achieve throughputs up to ten times faster than conventional CISC microcontrollers.