DATA PROCESSING SYSTEM PROVIDING LOCKED OPERATION OF SHARED RESOURCES

摘要

A central processing system which includes a plurality of units coupled over a common electrical bus for the transfer of information between any two units, includes one unit in which there is a shareable resource such as a memory for example. Apparatus is provided for any units to share such resource. Further apparatus is provided for enabling any of such units so sharing the resource to lock out any other unit which presents a specified control signal to the unit incorporating the resource.