CONTROL SYSTEM FOR COMMON BUS OCCUPANCY IN MULTII PROCESSOR SYSTEM

摘要

PURPOSE:To make it possible to perform bus occupancy control in the shortest time by using information on the port number of a bus port connected to a common bus at that time for bus occupancy control of each bus port by a bus supervisory control circuit. CONSTITUTION:Bus supervisory control circuit 1 sets the port number to zero and then make a decision on whether the number is registered in the memory of bus port 2 connected to common bus 1. When the decision is ''NO'', an advance is made without sending a polling command to bus port 2 of the number and the decision is made again. When ''YES'', the polling command is sent to bus port 2 of the port number and if a bus occupancy discrimination signal is sent back, it is considered that the right of bus occupation has been transferred. In case of time out, the port number is advanced to a decision on whether a connection port discrimination table has registration or not. Those operations are repeated in succession.