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bus




  1. A common pathway along which data and control signals travel between different hardware devices within a computer system. (A) When bus architecture is used in a computer, the CPU, memory, and peripheral equipment are interconnected through the bus. The bus is often divided into two channels, a control channel to select where data is located (address bus), and the other to transfer the data (data bus or I/O bus). Common buses are: ISA (Industry Standard Architecture) the original IBM PC 16 bit AT bus; EISA (Extended Industry Standard Architecture) the IBM PC 32 bit XT bus (which provides for bus mastering); MCA (MicroChannel Architecture) an IBM 32 bit bus; Multibus I & II (advanced, 16 & 32 bit respectively, bus architecture by Intel used in industrial, military and aerospace applications); NuBus, a 32 bit bus architecture originally developed at MIT (A version is used in the Apple Macintosh computer); STD bus, a bus architecture used in medical and industrial equipment due to its small size and rugged design (Originally 8 bits, with extensions to 16 and 32 bits); TURBO Channel, a DEC 32 bit data bus with peak transfer rates of 100 MB/second; VMEbus (Versa Module Eurocard Bus), a 32 bit bus from Motorola, et.al., used in industrial, commercial and military applications worldwide (VME64 is an expanded version that provides 64 bit data transfer and addressing). (B) When bus architecture is used in a network, all terminals and computers are connected to a common channel that is made of twisted wire pairs, coaxial cable, or optical fibers. Ethernet is a common LAN architecture using a bus topology.


  2. Part of a spacecraft's payload which provides a platform for experiments or contains one or more atmospheric entry probes.

Related category

   • COMPUTERS, ARTIFICIAL INTELLIGENCE, AND CYBERNETICS