Abstract: A data processing system having a flexible internal structure, protected from and effectively invisible to users, with multilevel control and stack mechanisms and capability of performing multiple, concurrent operations, and providing a flexible, simplified interface to users. The system is internally comprised of a plurality of separate, independent processors, each having a separate microinstruction control and at least one separate, independent port to a central communications and memory node. The communications and memory node is an independent processor having separate, independent microinstruction control and comprised of a plurality of independently operating, microinstruction controlled processors capable of performing multiple, concurrent memory and communications operations. Addressing mechanisms allow permanent, unique indentification of information as objects and an extremely large address space accessible and common to all such systems.

Abstract: A digital computer memory made up of a plurality of read only memory components arranged in a matrix of rows and columns. The outputs of the columns of memory components are connected to a voltage source and load resistors to provide the output terminals of the memory. Sets of digital words having at least a field or portion of a field with bits represented by the same logical state are grouped in such memory so that, when a word in such set is addressed, the bits in such field are produced at the output terminals by the volage source and load resistors. With such arrangement the number of read only memory components required in such memory is reduced.

Abstract: A microinstruction memory addressing control unit for a microprogram controlled digital computer is disclosed. The microinstruction memory stores an addressable fetch microprogram and independent sets of addressable microinstructions. Each one of the stored microinstructions in the sets thereof has an addressing control field. The microinstruction memory addressing control unit, in response to the microinstruction control field of a microinstruction currently under execution, is adapted to select as the next address for the memory one of a variety of addresses.