COMPUTER,MICROCOMPUTER AND MICROPROCESSOR
Microprocessors have evolved dramatically in the twelve years of their development by the implementation of large numbers of devices on single chips. Word widths have increased along with microprogramming capabilities, addressing capabilities, and trends toward single-chip computers. Only a year after the introduction of 4-bit processors came the 8-bit processor. Three years later, in 1974, 16-bit processors became the leading technology. The article compares architectures and operations of the TI 9900, Intel 8086, Zilog Z8000, Motorola 68000, and NSC 16032 16-bit microprocessors. The 32-bit processor was realized in 1981. General trends in architecture, technology, principles of operation, register organization, instruction set, memory organization, and performance are examined in the Bellmac-32A chip, the HP 32-bit processor, and the iAPX 432 processor chip set. With the development of advanced processors have come improvements and evolution of operating systems and processor communications. Multiprocessing and special-purpose processors have also improved computing technology. The processor technologies are illustrated by diagrams and compared in tables. A glossary of microprocessor terms is included.
A computer is a programmable machine that receives input, stores and manipulates data, and provides output in a useful format.
While a computer can, in theory, be made out of almost anything , and mechanical examples of computers have existed through much of recorded human history, the first electronic computers were developed in the mid-20th century (1940–1945). Originally, they were the size of a large room, consuming as much power as several hundred modern personal computers (PCs). Modern computers based on integrated circuits are millions to billions of times more capable than the early machines, and occupy a fraction of the space. Simple computers are small enough to fit into mobile devices, and can be powered by a small battery. Personal computers in their various forms are icons of the Information Age and are what most people think of as "computers". However, the embedded computers found in many devices from MP3 players to fighter aircraft and from toys to industrial robots are the most numerous.
In computer science and computer engineering, computer architecture or digital computer organization is the conceptual design and fundamental operational structure of acomputer system. It's a blueprint and functional description of requirements and design implementations for the various parts of a computer, focusing largely on the way by which thecentral processing unit (CPU) performs internally and accesses addresses in memory.
It may also be defined as the science and art of selecting and interconnecting hardware components to create computers that meet functional, performance and cost goals.
Computer architecture comprises at least three main subcategories.
• Instruction set architecture, or ISA, is the abstract image of a computing system that is seen by a machine language (or assembly language) programmer, including the instruction set, word size, memory address modes, processor registers, and address and data formats.
• Microarchitecture, also known as Computer organization is a lower level, more concrete and detailed, description of the system that involves how the constituent parts of the system are interconnected and how they interoperate in order to implement the ISA. 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:
1. System interconnects such as computer buses and switches
2. Memory controllers and hierarchies
3. CPU off-load...