A computer system consists of two parts: hardware and software. Software includes system software and application software.
MAR is a memory address register, which holds the address and number of memory cells, and the length reflects the number of memory cells.
MDR is a memory data register, which is used to store the data to be stored in the memory bank or the data just taken out from the memory bank, and its length reflects the length of the memory word. Use MAR and MDR to put data into memory.
System software can manage the whole computer system:
Language processor (converting high-level language into instructions that can be understood by the machine).
Operating system.
Service programs (such as parallel communication math libraries and MPI service programs).
Database management system.
Network software.
The structure of computer system defines the interface between software and hardware of the system, and defines which functions are realized by software and which functions are realized by hardware, which is defined as = = the attributes, conceptual structure and functional characteristics of computer system as seen by programmers = =. (instruction system, data type, addressing technology, I/O mechanism), that is, what programmers need to know.
Computer composition: the realization of the attributes embodied in the computer architecture, that is, the realization of specific instructions.
Application software is a program written according to the needs of the task.
We can simply regard software and hardware as a hierarchical structure. Hardware provides an interface for software, and system software forms an interface for application software to complete different programs.
For the physical structure of computer, our course mainly studies the concrete realization methods of logic layer and microcircuit layer.