Architecture Neumann Background

Architecture and structure

The architecture of computers may vary depending on the type of tasks being performed. Optimization of the computer architecture is carried out with the aim of maximally realistic mathematically modeling the physical (or other) phenomena under study. Thus, electron flows can be used as models of water flows in computer simulations (simulations) of dams, dams, or blood flow in the human brain. Similarly constructed analog computers were common in the 1960s, but today they are quite rare.

Architecture Neumann Background

Principles of von Neumann

Principle of uniformity of memory
Commands and data are stored in the same memory and are apparently indistinguishable in memory. Recognize them only by use; that is, the same value in a memory cell can be used both as data and as a *** a and as an address, depending only on the way it is accessed. This allows you to perform the same operations on a *** s one as on numbers, and, accordingly, opens up a number of possibilities. So, cyclically changing the address part of the command, you can provide access to consecutive elements of the data array. This technique is called the modification of commands and from the standpoint of modern programming is not welcome. More useful is another consequence of the principle of homogeneity, where commands from one program can be obtained as the result of executing another program. This possibility underlies the translation - translation of the program text from a high-level language to the language of a specific computer.
Targeting principle
Structurally, the main memory consists of numbered cells, and any cell is available to the processor at any time. Binary codes of commands and data are divided into units of information, called words, and are stored in memory cells, and the numbers of the corresponding cells are used to access them — addresses.
Principle of program management
All calculations provided by the algorithm for solving the problem should be presented in the form of a program consisting of a sequence of control words - commands. Each comma *** prescribes some operation from the set of operations implemented by the computer. Program commands are stored in successive memory cells of the computer and are executed in a natural sequence, that is, in order of their position in the program. If necessary, with the help of special commands, this sequence can be changed. The decision to change the order of execution of program commands is made either on the basis of an analysis of the results of previous calculations, or unconditionally.
Binary coding principle
According to this principle, all information, both data and commands, is encoded with binary numbers 0 and 1. Each type of information is represented by a binary sequence and has its own format. A sequence of bits in a format that has a specific meaning is called a field. In numerical information, the field of the sign and the field of significant digits are usually distinguished. In the command format, you can select two fields: the operation code field and the address field.