Dual mode bulk memory extension system for a data processing

Claim 1

A stored program data processing system comprising: a. a random access central memory having a first predetermined access time for storing data therein; b. a random memory extension having a second predetermined access time slower than the first predetermined access time for storing data therein; c. a plurality of data processors; d. memory control means having data channels connecting said data processors and said central memory to said memory control means said memory control means permitting the accessing of said central memory and said memory extension asynchronously and selectively by each of the plurality of data processors; e. a first data channel connecting said memory extension to said memory control means; f. a second data channel connecting said memory extension to said memory control means; g. a data channel controller for controlling the block transfer of data through said first data channel and said memory control means between said central memory and said memory extension; and h. a memory request controller, responsive to said plurality of data processors and to said memory extension, for controlling the transfer of data through said second data channel and said memory control means between said processors and said memory extension.