STAR COMMUNICATION NETWORK FOR PERSONAL COMPUTERS

Abstract

I►e purpose of Personal Computer Network is to interconnect autonomous personal computers. Autonomous system means that each, system works independently with the other one. Various 'topologies are possible for such type of networks: Star topology, Loop topology, free topology, Nus topology and Ring topology. Selection of any topology depends upon the requirement of the network. The work presented in the dissertation deals with the implementation of star topology on personal computers. In star trapc►1c►gy, each station is connected by a point to point link tp a common central switch. Communication between'any two stations is _ _done by the concept of circuit switching. Station, which wants to transmit a message, must send a request to central swi.tch,. asking for connection to some destination station. Once the circuit is set up, message may be exchanged in between the two stations as if they were connected by a dedicated point to point link. A hardware package has been developed as a central switch for the network. The control of swi.tch is done by the 8085 processor. Package consists of two cards, a CPU card and a MAIN card. The function of the CPU card is to provide signals required by the main card and the units of the CPU card. Main card is used for the hardware linking of the central switch with the stations and for the interrupts logic. After establishing a link, between the computers message data and files can easily be exchanged.