Table of Content  Branch Up  

Architecture

The LC-81 mini-computer consists of various rack mount units interconnected together by the mean of a proprietary 37-lines parallel bus called EXT-BUS.

A minimal configuration comprises the Master Controller (MC) and some other unit. The MC provides the intelligence to the system containing the microprocessor (Zilog Z80 CPU) and the first 24 KB of memory. The other units provide I/O resources, memory extension and, perhaps, specific functionality for a specific application.

As many units as needed can be connected throughout the EXT-BUS to conform a large equipment. Examples of possible extra units are: Tape Drive Controller, Disk Controller, Serial Ports, Printer Controller, Real-Time Timer, GPIO and many others.