1. Software version
vivado2019.2
2. Algorithm overview
Compared with the combinational logic controller, the microprocessor has a series of advantages such as regularity, flexibility, maintainability, etc., so it has gradually replaced the early combination logic controller in computer design and has been widely used. In computer systems, microprogramming technology is a technology that uses software methods to design hardware.
The basic idea of microprogram control is to imitate the method of the usual problem-solving program, compile the operation control signal into the so-called "micro-instruction", and store it in a read-only memory. When the machine is running, these micro-instructions are read out one by one, so as to generate various operation control signals required by the whole machine, so that the corresponding components can perform the specified operations. The controller using the micro-program control method is called a microprocessor. . The so-called micro-program control mode means that the micro-command is not generated by the combinational logic circuit, but is generated by the decoding of the micro-instruction. A machine instruction is often divided into several steps for execution, and several bit commands required for each step are written in a microinstruction in the form of code, and several microinstructions form one end of the microprogram, corresponding to one and its instructions. When designing the CPU, according to the needs of the instruction system, each segment of the microprogram is prepared in advance, and they are stored in a dedicated memory (called the control memory). The microprocessor consists of an instruction register IR, a program counter PC, a program status word register PSW, a timing system, a control memory CM, a microinstruction register and a microaddress to form a circuit. Micro-address registers and other components. When executing an instruction, find the corresponding micro-program segment from the control memory, fetch the micro-instructions one by one, send them into the micro-instruction register, and generate the required micro-commands after decoding to control the completion of each step operation.
The advantages of microprogram control