The wrong description about the CPU is that "in addition to storing instruction addresses, the program counter PC can also temporarily store arithmetic/logical operation results"; the program counter is a special register with two functions: registering information and counting.
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The wrong description about the cpu is "Program Counter PC In addition to storing instruction addresses, arithmetic/logical operation results can also be temporarily stored."
The correct one is:
CPU generates the operation signal for each instruction and sends the operation signal to the corresponding component for control
The controller in the CPU determines the automation of the computer running process
The instruction decoder is a component in the CPU controller
CPU It is the control center of the computer, mainly composed of arithmetic units, controllers, register groups and internal buses. The controller consists of a program counter, an instruction register, an instruction decoder, a timing generator and an operation controller. It is the "decision-making mechanism" that issues commands, that is, it coordinates and directs the operations of the entire computer system. Its main functions are: fetch an instruction from the memory and indicate the location of the next instruction in the memory; decode or test the instruction and generate corresponding operation control signals to initiate specified actions; command and control the CPU , the flow of data between memory and input and output devices.
The program counter (PC) is a special register that has two functions: registering information and counting. It is also called an instruction counter. Before the program starts executing, the starting address of the program is sent to the PC. This address is in the program Determined when loaded into memory, so the initial content of the PC is the address of the first instruction of the program. When an instruction is executed, the CPU will automatically modify the contents of the PC so that it always holds the address of the next instruction to be executed. Since most instructions are executed sequentially, the modification process usually involves simply adding 1 to the PC. When a transfer instruction is encountered, the address of the subsequent instruction is obtained based on the address of the current instruction plus a forward or backward shift amount, or based on the direct transfer address given by the transfer instruction.
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