Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: An apparatus and method to receive first service request signals and second service request signals from virtual signal queues, to map the virtual signal queues according to a first mapping, to arbitrate the first service request signals in accordance with the first mapping of the virtual signal queues, and to re-map the virtual signal queues according to a second mapping, different from the first mapping, to allow arbitrating of the second service request signals in accordance with the second mapping of the virtual signal queues.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: The invention relates to a crossbar switch controller including an input terminal configured to receive a set of service request signals from a set of virtual output queues each comprising a set of packets. The invention also includes a matrix circuit coupled to the input terminal and configured to represent the set of service request signals in the form of a matrix, wherein each service request signal is described by a row position M and a column position N. The invention further includes an output terminal configured to receive a portion of the set of packets during an epoch, an arbiter circuit configured to iteratively scan the matrix during the epoch and issue the set of grant signals to the virtual output queues to determine which service requests are granted, and an arbiter controller configured to initiate the arbiter circuit with an array of non-conflicting matrix elements.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: The invention relates to a crossbar switch controller including an input terminal configured to receive a set of service request signals from a set of virtual output queues each comprising a set of packets. The invention also includes a matrix circuit coupled to the input terminal and configured to represent the set of service request signals in the form of a matrix, wherein each service request signal is described by a row position M and a column position N. The invention further includes an output terminal configured to receive a portion of the set of packets during an epoch, an arbiter circuit configured to iteratively scan the matrix during the epoch and issue the set of grant signals to the virtual output queues to determine which service requests are granted, and an arbiter controller configured to initiate the arbiter circuit with an array of non-conflicting matrix elements.

Abstract: A communication circuit for verified communication comprising a transmitter having input terminals to receive a data word, an encoder configured to encode the data word to create an encoded word different from the data word, and output terminals configured to transmit the data word and the encoded word. A receiver is coupled to the transmitter and includes input terminals to receive the data word as a received word and the encoded word, a decoder configured to decode the encoded word to create a decoded word, and a comparator configured to compare the received word and the decoded word to create a select signal, and a selector responsive to the select signal and configured to select the received data word or the decoded word based at least in part on the select signal. Advantages of the invention include the ability to verify redundant received data without decreasing bandwidth or increasing latency.

Abstract: The invention relates to a crossbar switch controller including an input terminal configured to receive a set of service request signals from a set of virtual output queues each comprising a set of packets. The invention also includes a matrix circuit coupled to the input terminal and configured to represent the set of service request signals in the form of a matrix, wherein each service request signal is described by a row position M and a column position N. The invention further includes an output terminal configured to receive a portion of the set of packets during an epoch, an arbiter circuit configured to iteratively scan the matrix during the epoch and issue the set of grant signals to the virtual output queues to determine which service requests are granted, and an arbiter controller configured to initiate the arbiter circuit with an array of non-conflicting matrix elements.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: The invention relates to a crossbar switch controller including an input terminal configured to receive a set of service request signals from a set of virtual output queues each comprising a set of packets. It also includes a matrix circuit coupled to the input terminal and configured to represent the set of service request signals in the form of a matrix, wherein each service request signal is described by a row position M and a column position N. An output terminal is configured to receive a portion of the set of packets during an epoch, an arbiter circuit configured to iteratively scan the matrix during the epoch and issue the set of grant signals to the virtual output queues to determine which service requests are granted, and an arbiter controller configured to initiate the arbiter circuit with an array of non-conflicting matrix elements.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: The invention relates to a crossbar switch controller including an input terminal configured to receive a set of service request signals from a set of virtual output queues each comprising a set of packets. The invention also includes a matrix circuit coupled to the input terminal and configured to represent the set of service request signals in the form of a matrix, wherein each service request signal is described by a row position M and a column position N. The invention further includes an output terminal configured to receive a portion of the set of packets during an epoch, an arbiter circuit configured to iteratively scan the matrix during the epoch and issue the set of grant signals to the virtual output queues to determine which service requests are granted, and an arbiter controller configured to initiate the arbiter circuit with an array of non-conflicting matrix elements.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: A network switch includes an input layer to receive a data stream with a set of cells. Each cell includes data and a header to designate a destination device. The input layer includes a set of input layer circuits. A selected input layer circuit of the set of input layer circuits receives the data stream. The selected input layer circuit includes a set of queues corresponding to a set of destination devices. The selected input layer circuit is configured to assign a selected cell from the data stream to a selected queue of the set of queues. The selected queue corresponds to a selected destination device specified by the header of the selected cell. An intermediate layer includes a set of intermediate layer circuits, each intermediate layer circuit has a set of buffers corresponding to the set of destination devices.

Abstract: First and second banks of control stores are used to store microinstructions. Each bank contains three control stores: A horizontal control store, a vertical control store, and a jump control store. The horizontal control store contains the rank four microcode; the vertical control store contains the rank three microcode; and the jump control store contains the same microcode as the vertical control store but is used on conditional jump microoperations. This allows simultaneous accessing of different microinstructions using a single address incrementer. The control store banks are accessed in an overlapping manner so that upon each clock cycle one bank is loading the rank 3 and rank 4 registers. The sequencer according to the present invention includes a return address stack for returning from subroutine calls and trap routines.

Abstract: A processor interface chip and a maintenance diagnostic chip are provided coupled with two microprocessors designed to be run in tandem. The processor interface chip includes logic for interfacing between the microprocessors and a main memory, logic for pipelining multiple microprocessor requests between the microprocessors and main memory, logic for prefetching data before a microprocessor issues a read request, logic for allowing a boot to occur from code anywhere in physical memory without regard to the microprocessors' fixed memory location for boot code, and logic for intelligently limiting the flow of interrupt information over a processor bus between the microprocessors and the processor interface chip.

Abstract: A processor interface chip and a maintenance diagnostic chip are provided coupled with two microprocessors designed to be run in tandem. The processor interface chip includes logic for interfacing between the microprocessors and a main memory, logic for pipelining multiple microprocessor requests between the microprocessors and main memory, logic for prefetching data before a microprocessor issues a read request, logic for allowing a boot to occur from code anywhere in physical memory without regard to the microprocessors' fixed memory location for boot code, and logic for intelligently limiting the flow of interrupt information over a processor bus between the microprocessors and the processor interface chip.