Fourth generation of computers
The so-called fourth generation is the product of the microprocessor of electronic circuits. The reduced size of the chips made possible the creation of personal computers (PCs). Today LST (Large-Scale Integration) and VLSI (Large-Scale Integration) technologies Larger scale) allow hundreds of thousands of electronic components to be stored on a microchip. Using VLs, a manufacturer can make a small computer rival a first-generation computer that took up an entire room. The microcomputers did their great debut.
It made it an ideal computer for “personal” use, hence the term “PC” was standardized and clones later released by other companies were called “PC and compatible”, using processors of the same type as IBM but at a lower cost and being able to execute the same type of programs. There are other types of microcomputers such as the Macintosh, which are not compatible with the IBM, but which in many cases are also called "PC" because they are for personal use. The first microprocessor was the Intel 4004, produced in 1971. It was originally developed for a calculator, and was revolutionary for its time. It contained 2,300 transistors in a 4-bit microprocessor that could only perform 60,000 operations per second. The fourth generation computer is the most modern, the next is the fifth generation.
Microprocessors
The first 8-bit microprocessor was the Intel 8008, developed in 1972 for use in computer terminals. The Intel 8008 contained 3,300 transistors. The first truly general-purpose microprocessor, developed in 1974, was the 8-bit Intel 8080, which contained 4,500 transistors and could execute 200,000 instructions per second. Modern microprocessors have much greater capacity and speed.
These include the Intel (IBM PC) with 5.5 million transistors; Sun Microsystems' UltraSparc-II, which contains 5.4 million transistors; the PowerPC 620, jointly developed by Apple, IBM and Motorola, with seven million transistors; and the Alpha 21164A, from Digital Equipment Corporation, with 9.3 million transistors. The microprocessor is an electronic circuit that acts as the central processing unit of a computer, providing control of calculation operations.
Microprocessors are also used in other advanced computing systems, such as printers, automobiles, and airplanes. In 1995, some 4 billion microprocessors were produced worldwide. The microprocessor is a type of circuit extremely integrated. Integrated circuits, also known as microchips or chips, are complex electronic circuits made up of extremely small components formed into a single, thin, flat piece of a material known as a semiconductor.1lm Modern microprocessors incorporate up to 10 million transistors (which act as electronic amplifiers, oscillators, or more often as switches), plus other components such as resistors, diodes, capacitors, and connections, all in a footprint comparable to that of a postage stamp. A microprocessor takes care of the various different sections.
The more complex ones often contain other sections; For example, modern specialized memory sections called cache memory operate with a 64-bit bus width: this means that 64 bits of data can be transmitted simultaneously. An oscillating crystal in the computer provides a timing signal, or clock signal, to coordinate all the activities of the intel microprocessor.
Computers
The fourth generation computers were:
PDP-10: It was a computer made by DEC. Its architecture was almost identical to that of the PDP-6, as it shared the same 36-bit word length and the same slightly expanded instruction set. Most notable of this expansion were the "byte" instructions, which operated on bit fields of arbitrary size. DEC withdrew the PDP-10 product line from the market in 1983, because the VAX, which was also developed by DEC, was more economically profitable.
PDP-11: It was a computer developed by DEC and was the first microcomputer to interconnect all the elements of the system in a bidirectional and asynchronous communication bus. This device was called UNIBUS, and it allowed devices to receive, send, or exchange data without having to go through memory. It was also one of the first computers to run the UNIX operating system, developed at Bell Laboratories. It went from having a CPU made with TTL MSI circuitry to using microprocessors like the LSI-11. Due to the mass production of XENIX chips, the PDP-11 lost its cost advantages so that it was finally sold to Mentec Inc. in 1994. Later, in the late 1990s, both DEC and the entire computer industry in New England went bankrupt.
Cray-1: The Cray-1 was a supercomputer designed by a group of mathematicians headed by Seymour Cray for Cray Research. It was one of the most successful computers of its time. It operated with 80 MHz vector processors, was a 64-bit system, and weighed 5.5 tons including the freon cooling system. Despite its large size, it only had 8.8 MB of RAM.
Cray X-MP: The Cray X-MP was a computer designed, produced, and built by Cray Research. It was Cray Research's first multiprocessing, shared memory, vector processor computer. It was the successor to the Cray-1 and the fastest computer in the world between 1983 and 1985. Its main designer was Steve Chen. It was depicted in movies like Tom Clancy's The Hunt for Red October.