Abstract: A self-timed random access memory circuit is designed on a single monolithic integrated circuit chip. The chip includes a random access memory including addressable storage locations, address decoding circuitry, data input and output circuitry and write enable circuitry. In addition, the chip includes input latches connected to chip input terminals which store data, address and operation control signals from off-chip circuitry in response to a timing signal, also from the off-chip circuitry. Also in response to the timing signal, an output latch on the chip stores data from the random access memory for transmission to output terminals, where the data is available to the off-chip circuitry. The input and output latches permit the self-timed random access memory circuit to perform in a pipelined manner.

Abstract: A central processor for use in a data processing system that is adapted for addressing a substantially larger virtual memory than the address space defined by the memory address field in an instruction normally provides. Information identifying an extended address is placed in working registers of the central processor. Other working registers in the central processor receive information corresponding to the memory word addressed by the instruction word. If the memory word requires indexing, the central processor adds the contents of an index register to the address contained in the memory address field of the memory word. If the resultant address is extended, the arithmetic and logic unit's carry logic is not inhibited and the larger address space is provided to one of the working registers. Concurrently, control logic is set within the central processor which causes the central processor to interpret the information as an extended address.

Abstract: A memory control apparatus for use in a digital computer system. The computer system comprises a central processing unit and a main memory which has a plurality of memory units. The processor has control circuitry for simultaneously addressing a plurality of words stored in the memory locations in the memory units. The processor addresses the plurality of words by the combination of a memory address signal and word request control signal which are equal to the number of words to be transferred. While addressing of the memory units occurs in parallel, the transfer of words occurs serially. The initial word as defined by the memory address signal is transferred first with the remaining words transferred in ascending modulo four order. If one or more of the four words has not been requested, it is automatically skipped by the control apparatus with no loss in time or continuity.

Abstract: A memory unit for use with a central processor unit in a data processing system. To retrieve data from the memory unit, the central processor unit energizes an appropriate one of several memory retrieval control signal conductors and memory address signal conductors to initiate a memory cycle during which the memory unit transmits an address acknowledgement signal and data signals back to the central processor unit. The memory unit has a characteristic retrieval interval during which the memory cycle is performed to retrieve data. Each memory retrieval control signal corresponds to a different category of characteristic retrieval interval. When the memory unit transmits the data signals, it transmits a data control signal which is delayed with respect to the address acknowledgement signal by a time interval that is directly related to the characteristic retrieval interval for the memory unit.