MCA – Micro Channel Architecture

Micro Channel Architecture (MCA) is a bus architecture for older PCs. It is called a bus architecture because it defines how peripheral devices and internal components communicate across the computer’s expansion bus. Introduced by IBM in 1987, MCA was designed to take the place of the older AT bus, the architecture used on IBM PC-ATs and compatibles. For a variety of reasons, however, the industry never accepted the new architecture.