Introduction

The Econet system allows a number of computing machines to communicate with each other and to share resources. It is a local network intended for use in situations ranging from one room to a small group of buildings. Typically the Econet will be used in applications where each user station is a low cost machine, for instance an Acorn ATOM, and all of the stations are connected together by the network. Also on the network one would expect some stations to be machines with extra facilities, say disk file storage and a hard copy printer, these would normally be Acorn system 3 or 4 computers. Using a communication media such as the Econet these facilities may be made available to the user stations, indeed it is possible for it to appear to the users that their machines each have their own disk units etc. Taking into consideration the high cost of such peripherals in relation to the ATOM personal computer and the small time for which they are required by each user, the Econet provides savings in cost and increases in operational efficiency. Of course the Econet may also be used to transfer data or programs between stations and any one station can send information to all of the other stations. Connection to the network by a user is always optional and so users retain complete control over their own machines. Compare this with a time sharing system where all the remote terminals cease to function when the central machine goes down. Thus a large number of machines, varying in complexity and cost, may be connected together to great advantage in the classroom, laboratory or office using the Econet

The Econet is a bus network using cable transmission over two pairs of wires which go from one end of the network to the other connecting to all stations on the way. Information travels in a serial bit form over one pair of wires and the other pair carry the network clock. The Econet gives each station a fast access to any other station and it continues to operate if other stations are not working. The bus approach choosen for the Econet allows stations to communicate without involving a third party and the interface hardware is simple, it operates at high speed and the total length of cable required is minimised .

This manual describes the hardware required to implement the Econet, a Eurocard for the Acorn System 3 or 4 computers and a specially engineered circuit card for the Acorn ATOM personal computer. Also included is information on installing and terminating a network. Users should refer to the Econet Users Manual for a fuller description of local networking and software applications information.