Abstract: In a system having independently-clocked job-performing circuits (e.g., payload processors) and independently-clocked job-ordering circuits (e.g., request and payload suppliers), coordinating mechanisms are provided for coordinating exchanges between the independently-clocked circuits. The coordinating mechanisms include those that use transmitted time-stamps for scheduling contention-free performances within the job-performing circuits of requested jobs. The coordinating mechanisms additionally or alternatively include static and dynamic rate constraining means that are configured to prevent a faster-clocked one of the independently-clocked circuits from overwhelming a more slowly-clocked other of the independently-clocked circuits. In one implementation, independently-clocked telecommunication-shelves house a distributed set of line cards and switch cards.

Abstract: A digital switching system comprises: (a) a line card layer containing a plurality of real or virtual line cards; (b) a switch card layer containing a plurality of real or virtual switch cards; and (c) an interface layer interposed between the line card layer and the switch card layer for providing serialization support services so that one or more of the line cards and switch cards can be operatively and conveniently disposed in a first shelf or on a first backplane that is spaced apart from a second shelf or from a second backplane supporting others of the line cards and/or switch cards. Such an arrangement allows for scalable expansion of the switching system in terms of number of lines served and/or transmission rates served. The flexibility of the system is owed in part to payload data being carried within payload-carrying regions of so-called ZCell signals as the payload data moves between the line card layer and the switch fabric layer.

Abstract: A system and method in accordance with the invention produces an ECC code that is transmitted in they-bit domain along with data is converted from a native x-bit domain to they-bit domain. Such a system and method provides a representation of an ECC code that is part of a transmitted serial stream that allows clock recovery and that can use parity checking or other method to verity he integrity of the transmitted ECC code itself.

Abstract: A system and method in accordance with the invention produces an ECC code that is transmitted in the y-bit domain along with data that is converted from a native x-bit domain to the y-bit domain. Such a system and method provides a representation of an ECC code that is part of a transmitted serial stream that allows clock recovery and that can use parity checking or other method to verify the integrity of the transmitted ECC code itself.

Abstract: A control store unit having a control store address generator able to provide both the normal control store address generation functions, and the BIST/logout address generation functions. In response to a test enable signal, the address generator switches between two modes: a normal mode and a test mode. Under the normal mode, normal control store addresses are generated. Under the test mode, a sequence of BIST/logout addresses are generated that sequentially cycles through the entire control store memory at full CPU speed.

Abstract: A technique and system for reading instruction data from a cache memory with minimum delays. Addresses are calculated and applied to the cache memory in two or more cycles by a pipelined address generation circuit. While data at one address is being retrieved, the next address is being calculated. It is presumed, when calculating the next address, that the current address will return all the data it is addressing. In response to a miss signal received from the cache when no data at the current address is in the cache, the missed data is read from a main system memory and accessed with improved speed. In a system where the cache memory and processor operate at a higher clock frequency than the main system memory, new data is obtained from the main memory during only periodically occurring cache clock cycles. A missed cache memory address is regenerated in a manner to access such new data during the same cache clock cycle that it first becomes available from the main memory.

Abstract: A pipelined computer which process operand data through a sequence of D,A,T,B,X and W stages includes a sidetrack queue. Data which exits the B stage prematurely, before the X stage is ready to immediately process such data, is held over in the sidetrack queue and presented to the X stage at a later time. The sidetracking mechanism is used to speed processing of rate-variable operand-consuming instructions such as the EDIT and EDMK commands.

Abstract: A mapping system for mapping a plurality of two byte operation code series into a control store where in each two byte operation code the first byte identifies the series in which that two byte operation code is included and the second byte identifies that specific operation code within the identified series, the mapping system comprising a first register for storing the first and second bytes of a two byte operation codes, a first control store for storing control word for the two byte operation codes, a first means for generating, from the first and second bytes stored in the first register, a first control store address for the first control store thereby providing access to the control word for processing the two byte operation code store in the first register and a second means for generating, from the first and second bytes stored in the first register, a first signal when an invalid two byte operation code has been stored in the first register for processing, the first signal invalidating the processin

Abstract: An error recovery system used in a pipeline architecture type computer system for recovering from an error in a control word for an instruction without interrupting the sequence of processing control words by the computer system. The computer system processes instructions in a sequence of overlapping FLOWs where each FLOW is comprised of a sequence of cycles. An instruction control word is processed in each cycle of each FLOW. The error recovery system comprises a first storage for storing, for a given cycle of a FLOW, all the control words for all the instructions, a second storage for storing a control word read from the first storage and an error recovery logic for detecting an error in the control word read from the first storage and stored in the second storage and for correcting the error in the control word in the first and second storage.