To transmit or receive data from/to its peripherals, a computer uses either a serial or a parallel link, known as a "bus". Since the advent of personal computers (PCs), many different types of bus have appeared, their structure depending on the microprocessor used, the desired application and, above all, the manufacturer.
Communication between a machine and its peripherals is a subject as vast as it is complex. There are many standards, and given their potential, they cannot be covered in just a few pages. In this article, we'll be taking a look at the most popular standards in the IT world. We'll be concentrating on buses and connections to peripheral devices such as mice, printers, scanners, measuring devices, etc. We won't be looking at internal buses such as PCI (Peripheral Component Interconnect), ISA (Industry Standard Architecture), AGP (Accelerated Graphic Port), etc. Nor will we be describing the most important standards in the field of computer peripherals. Nor will we describe possible connections "via" computer or industrial networks, which are already the subject of articles in Techniques de l'Ingénieur (see Connecting an industrial process to a computer
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and Industrial local area networks. Typology and characteristics
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in the Industrial Computing treatise). We will therefore concentrate on a general presentation of the theoretical bases of buses and a description of a few essential standards: parallel links (§ 2), serial links (§ 3), Universal Serial Bus (USB) (§ 4) and GPIB-SCPI (§ 5).