PC compatible

Origins

With the beginning of the year 1980, a PC was a machine behaving like a IBM PC ( PC for Personal Computer literally “personal computer”) produced by IBM in 1981. One uses then the initials PC in opposition to the others personal computers which are not compatible with this first PC: Macintosh, Amiga, Commodore 64, Sinclair, Tandy, etc Thus, the category of the named personal computers PC is only one subset of the Personal computers.

The PC are built on the Microprocesseur S of architecture X86 of Intel. They were mainly used with the Operating system DOS, then Microsoft Windows. One has also spoken since the end about the Années 1990 about the platform WinTel to refer to Windows and Intel, the two most important actors of the market of the PC for this time. today, certain PC also make turn of other OS such as the Operating system Mac OS and Linux.

This name PC is used even in France, country where however the PC from IBM had been launched (almost two years after its world exit of 1981, because of the volume of translation to be carried out, then many corrections to bring there) under the name of Personal computer and not of Personal Computer .

History

In the beginning, PC was the name given by IBM to the first Micro-ordinateur S which it marketed as of 1981:

In 1981: IBM PC/G animated by the processor Intel 8088 (cheaper alternative of the 8086) frequency of clock 4,7 MHz. The equipment of starting and storage was composed of 1 to 2 readers 360 KB on floppy disc 5" 1/4.
In 1983: the IBM PC/XT which saw itself associating out of equipment of series Hard drive of 10 Mo and a communications card RS232. The equipment of filing was composed of 1 to 2 readers 360 KB on floppy disc 5" 1/4.
In 1984: IBM PC/AT with the processor Intel 80286. The equipment of filing was composed of 1 to 2 readers 360 KB or 1,2 Mo on floppy disc 5" 1/4.

For reasons speed of development, but as of market demand for second sources , IBM had preferred to create its PC by assembling standard components different manufacturers, rather as to create to them his as its competitors did it and, as it did it for its other computers.

The listing of BIOS being published, it became very easy of cloner IBM PC: it was indeed enough to buy the components with the same manufacturers then to recopy (with some difference) the Read-only memory (ROMANIAN) of BIOS to obtain a microcomputer says “PC compatible”. In the long term, IBM having lost all to be able of influence on the PC compatibles, one more simply called them PC, and it is a document published each year by Intel and Microsoft which defines which machine, according to the criteria of this year, is or is not already any more one PC (if what you believe being one of your PC does not have catches USB, for example, it is not strictly speaking more one PC within the meaning of Intel and Microsoft). In short, the standard has simply changed of owner .

In the beginning, the Operating system delivered with these first machines was:

PC-DOS (Microsoft marketing, him, the MS-DOS which indicated just two vital files under a different name: IBM.SYS became MSDOS.SYS and IBMIO.SYS became IO.SYS),
CP/M 86 of DIGITAL Research
the PC/IX, slow clone and without protections memory hardware of UNIX, quickly abandoned.

In 1987, IBM tried to change this architecture into creating the models IBM PS/2 provided with a new bus faster, called MCA for Micro Chanel Architecture (open, but this time against payment of a license), and functioning either under DOS, or with its operating system OS/2. The material remaining however very close to the PC, the PS/2 could function with other operating systems.

But architecture PC had already created a standard in fact , because it had been copied by a great number of manufacturers, and even improved from some points (board graphics Hercules and Ericsson). Only PS/2 by the other manufacturers was thus preserved:

resolutions of screen VGA and XGA (although they were very slow on a bus AT, renamed in fact ISA)
diskettes 3,5 inches 1,44 Mo, although Compaq is not favorable there and announced it.
the standard of connection of the keyboard and mouse (mini-DIN 9 pins, known under the name of port PS/2) in opposition to the mice on port series and to the keyboards with port “AT” (taken standard DIN).

The bus was however to be changed to manage in an acceptable way the new resolutions of screen. One tested local VESA in turn bus , EISA , the NCV , which was a success, AGP , and finally the PCI Express . As for the Random access memory (RAM), it resided either on charts plugged in at same the bus, but on the mother board which reached it by a circuit dedicated without passing by the bus, idea already used by Compaq with architecture FLEX of sound Desktop 386 .

Today

The great force of architecture PC is that competition plays on all levels: one can choose the mark of the Microprocesseur, of the Mother chart, the video Carte, compatibility between the components souvant being ensured, for components of the same time.

Contrary, the first computers Macintosh sold by the company Apple, were not it. This firm authorized then manufacture against payment of rights of a few series of clones, but cancelled in 1997 the licenses of its operating system conceded with the other manufacturers.

One speaks sometimes about “the platform Wintel ”, for a computer functioning with a Microprocesseur of the family X86/Pentium of Intel and using an operating system Windows from Microsoft. Term PC indicates the material well, but confusion between PC and PC/Windows remained very current. The new versions of the distributions GNU/Linux with their Mozilla and well ground OpenOffice as well as the passage of Apple to architecture PC could change gives it.

Intel is not the only one to provide microprocessors for PC: AMD, Via and Transmeta functionally produces compatible microprocessors (but not in Brochage) with those of the x86/Pentium family.

In the middle of the years 1990, the founder (chipmaker electronic) Cyrix also proposed processors for PC, but was not interested in the implementation of a Coprocesseur of floating-point calculation (with reason, technically, because even of the graphic products as CorelDraw did not make no use of it). On the marketing plan, however, this gap torpedoed its products vis-a-vis the 80486 which was equipped with it out of standard.

The PC remains, since the middle of the Eighties, the machine general public par excellence, other architectures remaining largely the prerogative of particular applications, in particular thanks to/because of the domination of the Operating system Windows which is not, made remarkable, adapted that to this type of machine. The principal alternative to the PC was for a long time the computer Macintosh (or Mac) of the company Apple. But since 2005, Apple sells its mac computers provided with processors Intel, thus giving them an architecture close to a PC and allowing the installation of Windows in addition to the Operating system Mac OS X.

Principal the operating systems adapted to this architecture is Windows, Linux, Mac OS X (since the passage to the Intel processors of the computers of Apple, although it is illegal to install Mac OS X on a computer PC which is not Apple mark), FreeBSD and Solaris.

Software

Contrary to the generally accepted idea , from the point of view of the user, the Architecture of the computer or even the Operating system imports little: in fact the applications are seen by the users.

A commercial fight is in hand for the control of the data-processing market. This is why the marketing policy of such or such data-processing company, and of the legal concepts such as those related to the inetllectuelle property, can influence the specific applications available under such or such configuration more than of alleged technical impossibilities.

However, from a point of view practices/technical, to make function the software users, such as the access or office automation softwares to Internet, of the software systems are necessary. On a PC, the software system available are the Bios and the operating system.

In a simplified way, one can consider that the software is dependant on its compatibility with the operating system, and that the operating system is dependant on its compatibility with the material. For example, the Word software does not function on a PC equipped with Linux, but functions on a PC equipped with Windows. Linux can function on a PC or a sun. Windows can function on a PC, but not on a sun. Word 2007 functions under Windows, but not under Windows 98. Windows Vista functions on a recent PC, but not on an old PC.

Bios

Bios makes it possible to make start the computer in the absence of operating system. It is integrated into the PC, and invisible of the user.

Operating system

The operating system make the interface between the PC (material) and the other software. on PC can in particular turn:

Windows
Linux
Mac OS X (since the passage to the Intel processors of the computers of Apple),
FreeBSD
Solaris.

Structure

Components

The architecture of a PC is based on that of Von Neumann, centered on the data processing, with:

a system of treatment

Mother chart, Microprocessor (List of microprocessors), Chipset

Of the Drunk Data buses

: ISA, EISA, NCV, AGP, PCMCIA
Drunk: SCSI, IDE, Serial ATA

Of the storage systems of data (also being able to be seen as systems of exit of data)

rewriteable Mémoire

has chance access (RAM)

Random access memory (RAM) (and derived)
Mémoire flash
Clé USB

has semi-sequential access

Disquette S (3 1/2, 5 1/4)
CD-RW, DVD R/W
Hard drive

has sequential access

Magnetic bands

nonerasable Mémoire (ROMANIAN)

PROM (EPROM, EEPROM)
CD-R, DVD-R or DVD+R

Of the systems of input

Clavier, Souris
Numeric camera, numerical camera, Webcam, Scanneur S
Carte its, micro

Of the systems of exits of data

video Chart, monitor, screen with liquid crystals TFT, Vidéoprojecteur
Printing, Plotting table
Chart its, pregnant
Digital music player

Of the systems of entry and exits of data

Internet, networks data processing, Wi-Fi, waiter

Bonds between the components

The components are dependant between them by:

Of the buses (internal communications to the case of the computer)
Of the ports (communications external to the case of the computer

Information to be transmitted is of several type (its, video data etc…) and come from modules distinct from the computer. In order to avoid errors of connection (short-circuit, loss of data), the cables have at their end of the different connectors which play the part of locating pin. Nowadays there exist 4 ports basic data processing:

the USB (data communications)
the video port (analogical video data, for écrants CRT)
the port digital video (given digital videos, for screens LCD)
jack 3.5 (its analogical, for the enclosures)
optics (its numerical, for the numerical enclosures)

Anecdotes

Pourquoi the French keyboard have does a key µ?

See too

Data-processing
Computer
Personal computer
Mini PC
Intel
AMD
List of plays PC
PC/G and PC/XT

Random links:

Anne Reynaud-Guérithault | Naisho No half moon | Verneil | Adlung | Park of Béning