Computer architecture

^{Computer architecture}

^{Computer architecture is a specification detailing how a set of software and hardware technology standards interact to form a computer system or platform. In short, computer architecture refers to how a computer system is designed and what technologies it is compatible with.}

^{As with other contexts and meanings of the word architecture, computer architecture is likened to the art of determining the needs of the user/system/technology, and creating a logical design and standards based on those requirements.}

^{A very good example of computer architecture is von Neumann architecture, which is still used by most types of computers today. This was proposed by the mathematician John von Neumann in 1945. It describes the design of an electronic computer with its CPU, which includes the arithmetic logic unit, control unit, registers, memory for data and instructions, an input/output interface and external storage functions.}

^{There are three categories of computer architecture:}

^{System Design: This includes all hardware components in the system, including data processors aside from the CPU, such as the graphics processing unit and direct memory access. It also includes memory controllers, data paths and miscellaneous things like multiprocessing and virtualization.}

^{Instruction Set Architecture (ISA): This is the embedded programming language of the central processing unit. It defines the CPU's functions and capabilities based on what programming it can perform or process. This includes the word size, processor register types, memory addressing modes, data formats and the instruction set that programmers use.}

^{Microarchitecture: Otherwise known as computer organization, this type of architecture defines the data paths, data processing and storage elements, as well as how they should be implemented in the ISA.}

^{Some practitioners of computer architecture use more fine subcategories:}

^{Macroarchitecture: Architectural layers that are more abstract than microarchitecture, for example ISA.}

^{Instruction Set Architecture (ISA): As defined above.}

^{UISA (Microcode Instruction Set Architecture): A family of machines with different hardware level microarchitectures may share a common microcode architecture, and hence called a UISA.}

^{Assembly ISA: A smart assembler may convert an abstract assembly language common to a group of CPUs into slightly different machine language for different CPUimplementations.}

^{Programmer Visible Macroarchitecture: Higher level language tools such as compilers may define a definite interface to programmers using them, abstracting differences between underlying ISA, UISA, and microarchitectures; for example the C, C++, or Java standards define three different definite programming interfaces.}

^{Pin Architecture: The set of functions that a microprocessor is expected to provide, from the point of view of a hardware platform. For example, signals that the processor is expected to emit during executing an instruction.}

^{Computer architecture includes at least three main subcategories:[1]}

^{Instruction set architecture, or ISA, is the abstract model of a computing system that is seen by a machine language (or assembly language) programmer, including theinstruction set, memory address modes, processor registers, and address and data formats.}

^{Microarchitecture, also known as Computer organization is a lower level, a detailed description of the system that is sufficient for completely describing the operation of all parts of the computing system, and how they are inter-connected and inter-operate in order to implement the ISA.[2] The size of a computer's cache for instance, is an organizational issue that generally has nothing to do with the ISA.}

^{System Design which includes all of the other hardware components within a computing system such as:}

^{System interconnects such as computer buses and switches.}

^{Memory controllers and hierarchies.}

^{CPU off-load mechanisms such as direct memory access.}

^{Issues like multi-processing.}

^{Once both ISA and microarchitecture has been specified, the actual computing system needs to be designed into hardware. This design process is called implementation. Implementation is usually a hardware engineering design process.}

^{Implementation can be further broken down into three but not fully separate pieces:}

^{Logic Implementation: Design of blocks defined in the microarchitecture, mainly, at the register-transfer and gate levels.}

^{Circuit Implementation: Transistor-level design of basic elements (gates, multiplexers, flip-flops, etc.) as well as of some larger blocks (ALUs, caches etc.) that may be implemented at this level, or even at a lower physical level, for performance reasons.}

^{Physical Implementation: Physical circuits are drawn out, the different circuit components are placed in a chip floor-plan or on a board and the wires connecting them are routed.}

Адрес публикации: https://www.prodlenka.org/metodicheskie-razrabotki/325398-computer-architecture