System for transferring multiple vector data elements to and from vector

Abstract

Apparatus for performing vector operations on the data elements of vectors includes a vector processor for performing arithmetic operations on the elements, a vector memory for storing the data elements for use by the processor, the vector memory having a port for reading and writing, and at least one staging register interposed between the vector memory port and the processor; the port and the register are each sufficiently wide to span more than one data element. As a result, on average fewer than one read or write operation per data element is required to access the vector memory via the port. Access to the vector memory port (i.e., a shared resource) is managed between a number of users by preassigning each user time slots that occur from time to time in each of which only one user is premitted to request access to the vector memory port, establishing a nominal priority ranking of types of requests made by the users for governing the order in which the users will be served, providing an arbitration mechanism for resolving conflicting requests by the users for access to the vector memory port based on the types of requests, and modifying the nominal priority ranking to temporarily lower the priority of a type of request made by a user that has previously been given access to the vector memory port as a result of the arbitration mechanism but has been unable to execute the access.