The CPU module is divided into three parts, namely the combinational logic of functions that perform operations on bits, the memory elements (registers) that store bits, and the clock signal that controls the update of memory elements. The basic task of a CPU is to execute instructions, and for a computer, they are ultimately a series of '0s' and' 1s'. The CPU can be logically divided into three modules: control unit, operation unit, and storage unit, which are connected through the CPU's internal bus.
CPU is a type of large-scale integrated circuit that is the core of computer operation and control. Its function is to interpret computer instructions and process data in computer software. The SMIC processor includes arithmetic logic components, register components, and control components, and has functions such as processing instructions, executing operations, controlling time, and processing data.
The main components of the CPU module are as follows:
1. Control unit
The control unit is the command and control chip of the entire CPU. It is very important to coordinate the orderly operation of the entire computer through the instruction register IR, instruction decoder ID, and operation controller OC. It sequentially retrieves each instruction from the memory based on the user's pre programmed program, places it into the instruction register IR, and determines the operation to be executed through instruction decoding (analysis). Then, the operation controller OC sends micro operation control signals to the corresponding components according to the determined timing. The control logic of OC includes a beat pulse generator, a control matrix, a clock pulse generator, a reset circuit, and a start stop circuit.
2. Operation unit
It is the core of the algorithm. It can perform arithmetic operations (including basic operations such as addition and subtraction multipliers and their additional operations) and logical operations (including shifts, logical tests, or binary comparisons). Compared to the control unit, the operator receives instructions from the control unit and takes action. That is to say, all operations performed by the operating unit are guided by control signals sent by the control unit, so it is the executing part.
3. Storage unit
The storage unit of the CPU module includes the CPU on-chip cache and register group, which are temporary storage places for data in the CPU. It saves data that is waiting to be processed or has already been processed. The time it takes for the CPU to access registers is shorter than the time it takes to access memory. By using registers, the number of times the CPU accesses memory can be reduced, thereby improving the CPU's working speed. However, due to limitations in chip area and integration, the capacity of the register group is not large. Register groups can be divided into special registers and general registers. The function of dedicated registers is fixed, and the corresponding data is stored separately. Universal registers are widely used and can be set by programmers. The number of general-purpose registers varies depending on the microprocessor.