Abstract: A microprocessor-based system serves as a message routing switch for communication between a number of different devices. Any device attached to the switch can communicate with any other attached device through a number of serial and parallel Input/Output ports. Communication between devices attached to the switch is in one of two formats. In a first method of communication, an attached device can be directly associated with another attached device in which case any communication from one is immediately transmitted to the other. In a second method of communication, an attached device communicates with the switch by means of fixed format packets, each of which contains a specification of its destination and error checking capabilities. This second method of communication permits examination of the validity of messages transmitted to or from the switch and enables message retransmission in the case of error.

Abstract: A processor is described which achieves highly parallel execution of programs represented in data-flow form. The language implemented incorporates conditional and iteration mechanisms, and the processor incorporates practical data-flow processing of a Fortran-level data-flow language. The processor has a unique architecture which avoids the problems of processor switching and memory/processor interconnection that usually limit the degree of realizable concurrent processing. The architecture offers an unusual solution to the problem of structuring and managing a two-level memory system.

Abstract: A digital computer may be structured in two separate sections, one of which performs the execution of arithmetic and conditional instructions, and the other which contains and performs operations upon data structures. The organization of the structure processing section of a digital computer is described herein. The structure processing section maintains data structures represented as acyclic directed graphs and is viewed as a functional unit by the instruction processing section; that is, instructions specifying structure operations are sent to the section, and any resulting values are returned to the instruction processing section. The organization of the structure processing section permits the simultaneous processing of many structure operations.

Abstract: A processor is described which achieves highly parallel execution of programs represented in data-flow form. The processor operates in a data-driven fashion; that is, an instruction of a program in the processor is enabled for execution upon the arrival of all required operands, and upon being executed, sends copies of the resulting value to all instructions which require it for their execution. The processor incorporates a form of deadlock prevention between the instructions of a data-flow program, allowing a value to be generated by an instruction and sent to the successor instructions in the computation only when those instructions are ready to receive the value. The incorporation of this mechanism prevents the possibility of conflict between successive stages of a pipelined computation and between successive iterations of an iterative computation.

Abstract: In a noise reduction system of the type in which an audio signal is delayed in time to permit detection of and reaction to impulse noise before application of the audio signal to a loudspeaker or the like, a transformed version of the audio signal is compared with its time-averaged value, and a resulting detection signal is processed into a control signal with blanking periods that vary as a function of corresponding impulse noise. The detection produces a response to both large impulses which stand out from the audio signal and small impulses which are hidden in the audio signal. The control signal tailors its response to the size of the impulse, blanking the audio signal substantially only for the duration of the impulse. Auxilliary circuitry is provided.

Abstract: This invention is a new concept for the organization of digital data processing apparatus, suitable for highly parallel execution of certain computations involving repeated patterns of computational operations. Possible applications include many types of signal processing computations such as filtering, modulation and waveform generation. The invention permits exploitation of the unique properties of asynchronous digital logic.