Computer system with interface for expansion options board - has control signal output system on options board and signal selection circuit in interface with reduced number of interface lines

摘要

The computer installation with an interface for an options board for expanded functionality contains a plug connector (20) for the options board (10) to the interface (5) for data and different interface signals transfer between the interface and the board. Interface lines (IL1,IL2) carry data and interface signals between the board and the installation. A control signal output circuit on the board forms a control signal (CS) for selecting an interface signal required from the installation for operation of a special circuit on the board, when connected to the installation. An interface selection circuit is used for data exchange and for delivering the selected signal from the computer to the board. USE/ADVANTAGE - For lap-top and document car computers, with reduced number of interface lines.