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Peripheral Devices
A peripheral or peripheral device is an auxiliary device used to put information into and get information out of a computer. The term peripheral device refers to all hardware components that are attached to a computer and are controlled by the computer system, but they are not the core components of the computer, such as the CPU or power supply unit. In other words, peripherals can also be defined as devices that can be easily removed and plugged into a computer system.
Several categories of peripheral devices may be identified, based on their relationship with the computer:
- An input device sends data or instructions to the computer, such as a mouse, keyboard, graphics tablet, image scanner, barcode reader, game controller, light pen, light gun, microphone and webcam;
- An output device provides output data from the computer, such as a computer monitor, projector, printer, headphones and computer speaker;
- An input/output device performs both input and output functions, such as a computer data storage device (including a disk drive, solid-state drive, USB flash drive, memory card and tape drive), modem, network adapter and multi-function printer.
Many modern electronic devices, such as Internet-enabled digital watches, keyboards, and tablet computers, have interfaces for use as computer peripheral devices.
In computing, a peripheral bus is a computer bus designed to support computer peripherals like printers and hard drives. The term is generally used to refer to systems that offer support for a wide variety of devices, like Universal Serial Bus, as opposed to those that are dedicated to specific types of hardware. Serial AT Attachment, or SATA is designed and optimized for communication with mass storage devices.
This usage is not universal, some definitions of peripheral bus include any bus that is not a system bus, including examples like PCI. Others treat PCI and similar systems as a third category, the expansion bus.
CPI’s precursor, Holley Computer Products, was formed as a joint venture between Control Data Corporation (CDC) and the Holley Carburetor Company in April 1962. Holley developed and produced a series of drum printers. In June 1964, CDC bought out Holley and partnered with NCR and ICL to form CPI in Rochester.
In the early 1970s CPI also had a branch in Valley Forge, Pennsylvania. This division made punched card readers and 9-track magnetic tape drives for both parent companies (CDC and NCR).
In 1978 CDC bought controlling interest of CPI. CPI produced several train printers under the CDC and Fastrain brands, including the CDC Model 512 (1967), the Fastrain A 1200 LPM (1969) and the Fastrain 9372-III 2000 LPM (1976).
In 1977, CPI began manufacturing printers at a factory in Stevenage, Herts, UK that was originally used for the manufacture of ICL1900 computers. By 1979, the factory also made 9-track tape drives which were used in ICL and CDC computers, and were sold with industry-standard interfaces for use with other manufacturer’s computers.
In 1982, CDC acquired a controlling interest in Centronics in exchange for CPI and $25 million in cash. CPI was merged into Centronics and eventually the Rochester facility was closed.