The main frequency of CPU is also called frequency. The higher the CPU frequency, the better the performance. The higher the main frequency of CPU, the faster operation or instruction can be processed in a shorter time. CPU appeared in the era of large-scale integrated circuits, and the iterative update of processor architecture design and the continuous progress of integrated circuit technology promoted its continuous development and perfection.
Since its birth, CPU has developed rapidly, from being dedicated to mathematical computing at first to being widely used in general computing, from 4-bit to 8-bit, 16-bit, 32-bit processor, and finally to 64-bit processor, from the incompatibility of various manufacturers to the emergence of different instruction set architecture specifications. CPU has been developed for more than 40 years. We usually divide it into six stages.
principle of operation
Von Neumann architecture is the foundation of modern computer. In this architecture, programs and data are stored in a unified way, and instructions and data need to be accessed from the same storage space and transmitted through the same bus, so they cannot be executed overlapping. According to Von Neumann system, the work of CPU is divided into the following five stages: instruction fetch stage, instruction decoding stage, instruction execution stage, access number and result write-back.
Instruction fetch (IF) is the process of fetching an instruction from main memory to the instruction register. The value in the program counter indicates the position of the current instruction in main memory. When an instruction is fetched, the value in the program counter (PC) will automatically increase according to the length of the instruction word.