The Peripheral Interface Adapter (PIA) is a peripheral integrated circuit providing parallel I/O interfacing capability for microprocessor systems. Common PIAs include the Motorola MC6820 and MC6821, and the MOS Technology MCS6520, all of which are functionally identical but have slightly different electrical characteristics. The PIA is most commonly packaged in a 40 pin DIP package For an account of the words periphery and peripheral as they are used in biology, sociology, politics, computer hardware, and other fields, see the periphery disambiguation page. ... An integrated circuit (IC) is a thin chip consisting of at least two interconnected semiconductor devices, mainly transistors, as well as passive components like resistors. ... Microprocessors, including an Intel 80486DX2 and an Intel 80386 A microprocessor (abbreviated as µP or uP) is an electronic computer central processing unit (CPU) made from miniaturized transistors and other circuit elements on a single semiconductor integrated circuit (IC) (aka microchip or just chip). ... Motorola (NYSE: MOT) (TYO: 6686) started as Galvin Manufacturing Corporation in 1928. ... MOS Technology, Inc. ... IC in a DIP14-Package In electronics, a Dual In-line Package (DIP), sometimes called a DIL package, is an electronic device package with a rectangular housing and a row of electrical connecting pins along each of two opposite sides, usually the longer sides of the rectangle. ...

The PIA is designed for glueless connection to the Motorola 6800 style bus, and provides 20 I/O lines, which are organised into 2 8-bit bidirectional ports (or 16 general-purpose I/O lines) and 4 control lines (for handshaking and interrupt generation). The directions for all 16 general lines (PA0-7, PB0-7) can be programmed independently. The control lines can be programmed to generate interrupts, automatically generate handshaking signals for devices on the I/O ports, or output a plain high or low signal. The 6800 is a microprocessor produced by Motorola and released shortly after the Intel 8080 in 1975. ... The Bus, established by Mayor Frank Fasi, is Honolulus only public transit system. ...