Abstract: A communications bus operates using transition coding, for example NRZI coding, with transition-dominant signalling. That is, when the signal takes a first binary value, binary “1”, the component drives the bus line to its opposite state, and, when the signal takes a second binary value, binary “0”, the component does not actively drive the bus line. During arbitration, each arbitrating component writes a unique arbitrand onto the bus, and arbitration is lost by each component that writes a binary “0” when at least one other component writes a binary “1”. The components preferably do not use transition-dominant signalling when transmitting data payloads. For such traffic they actively drive the binary “0”s as well as binary “1”s.

Abstract: A data check circuit comprising: a request signal output circuit configured to output a request signal for requesting occupation of a bus to an arbitration circuit configured to arbitrate the occupation of the bus, when a CPU connected, as a bus master, with the bus for accessing a memory outputs an instruction signal for providing an instruction for starting detection of whether or not data stored in the memory is correct; a data acquisition circuit configured to acquire data stored in the memory through the bus, when the arbitration circuit outputs a permission signal for permitting the occupation of the bus based on the request signal; and a data processing circuit configured to perform processing for detecting whether or not the acquired data is correct, the acquired data acquired by the data acquisition circuit.

Abstract: This invention provide a data processor capable of multiplexing data transfers with desired data transfer characteristics guaranteed, without multiplexing buses. The data processor includes: a transfer path that mutually connects plural processors and plural transfer element circuits such as memory; an arbitration circuit that controls data transfer in the transfer path; and a control register that defines the priority and minimum guaranteed bandwidth of data transfer. The arbitration circuit decomposes data packets sent from plural data transfer sources into subunits, and reconstructs plural data packets having the same data transfer target, based on priority and minimum guaranteed bandwidth stored in a control register. Thereby, the one reconstructed data packet can include subunits of plural data packets from transfer sources having different priorities, and data amounts of subunits contained in it can satisfy minimum guaranteed bandwidth of data transfer.

Abstract: An IO processor includes an embedded central processing unit (CPU), a switch connected to the embedded CPU, an external CPU bus controller connected to the switch for optionally connecting to an external CPU, a first memory controller connected to the switch for connecting to a first memory, and a second memory controller connected to the switch for optionally connecting to a second memory. The IO processor may be connected to the external CPU, to the second memory, or be capable of connecting to external CPUs of different ranks, depending on the situation, so as to meet the cost considerations and the actual application requirements.

Abstract: A computer system including a plurality of PCIe paths is configured such that a failed PCIe path only is disabled, thereby preventing the computer system from system resetting. The computer comprises a root port for detecting a failure on a PCIe path, and then for issuing a SMI (System Maintenance Interrupt) to a CPU; and the CPU for, on the receipt of the SMI, executing BIOS to issue, through the root port, a PCIe reset to the PCIe path on which the failure has occurred.

Abstract: There is provided a transfer apparatus having a bridge that transfers a transaction between a first and a second bus, and a data transfer unit that performs a data transfer by DMA between the first and second bus. The transfer apparatus controls a transfer sequence of transaction transfers by the bridge and data transfers by the data transfer unit, in which transaction transfers by the bridge are based on bus sequencing rules and data transfers by the data transfer unit are based on a data transfer activation condition.

Abstract: Crossbar circuitry, and a method of operation of such crossbar circuitry, are provided. The crossbar circuitry has an array of data input paths and data output paths where the data output paths are transverse to the data input paths. At each intersection between a data input path and a data output path, a crossbar cell is provided that comprises a configuration storage circuit programmable to store a routing value, a transmission circuit, and an arbitration circuit. In a transmission mode of operation, the transmission circuit is responsive to the routing value being a first value, indicating that the data input path should be coupled to the data output path, to detect the data input along the data input path, and to output an indication of that data on the data output path at the associated intersection.

Abstract: A statistical-information generating unit monitors packet data output from a transaction layer that constitutes architecture of a PCI Express. The result of the monitored is feedback-controlled to a weight-information updating unit in real time, and is reflected in an arbitration table. A priority is set to the packet data corresponding to a quantity of the packet data actually transferred on a serial communication path.

Abstract: A method for pipeline arbitration including receiving a first request for a shared chip interface from a first pipeline, determining whether a response bus of the shared chip interface is needed by the first request, and if it is determined that the response bus is not needed by the first request, concluding that the first request needs just an address bus of the shared chip interface, arbitrating the first request with a second request for the shared chip interface received from a second pipeline for access to the address bus, sending the first request to the address bus if the first request wins the arbitration over the second request, and rejecting the first request if the second request wins the arbitration over the first request. A corresponding system and computer program product.

Abstract: Bus transfer efficiency is improved in bus communication that uses a shared memory, based on a communication origin master 101 selectively using an arbitration completion notification signal and a memory access completion notification signal. Based on the arbitration completion notification signal, the communication origin master 101 issues a command issue permission signal to the communication destination master 102, and the communication destination master 102 generates and issues a command for accessing the shared memory 12. Based on the memory access completion notification signal, the communication origin master 101 issues a command issue permission signal to the communication destination master 102, and the communication destination master 102 generates and issues a command for accessing the shared memory 12.

Abstract: A telecommunications system and constituent two-wire interface module. The two wire interface module includes a logic component configured to communicate over the same pair of wires using different two-wire interface protocols depending on an input signal presented on a configuration input. This configurability allows the two-wire interface module to use the same two wires to communicate with a variety of other two-wire interface modules, even if those two-wire interface modules communicate using different two-wire interface protocols.

Abstract: A method and system for bus arbitration to be used in a system having a plurality of data handling units (110a, . . . , 110d) and a shared bus (140) with a plurality of data-lines. The invention provides a method and an system to carry out the method, having steps of; receiving data transfer requests from the data handling units; selecting a set of data transfer requests the allowance of which serves a maximum number of data handling units and utilizes a maximum number of data-lines, and; allowing the data handling units that issued said selected set of data transfer requests to access said bus in a single bus cycle.

Abstract: A PCI Express system comprising: a PCI Express adapter; and a PCI Express root complex coupled to the PCI Express adapter, the PCI root complex including: a protocol stack coupled to the PCI express adapter and configured to transmit information to and receive information from the PCI express adapter; an application specific logic module; and a fencing module coupled between the application specific logic module and the protocol stack and configured to, when in operation, block all signals from the application specific logic module from reaching the protocol stack.

Abstract: A memory controller uses a power- and performance-aware scheduler which reorders memory commands based on power priorities. Selected memory ranks of the memory device are then powered down based on rank localities of the reordered commands. The highest power priority may be given to memory commands having the same rank as the last command sent to the memory device. Any memory commands having the same power priority can be further sorted based on one or more performance criteria such as an expected latency of the memory commands and an expected ratio of read and write memory commands. To optimize the power-down function, the power-down command is only sent when the selected memory rank is currently idle, the selected memory rank is not already powered down, none of the reordered memory commands correspond to the selected rank, and a currently pending memory command cannot be issued in the current clock cycle.

Abstract: Various methods and processing systems are disclosed which include sending and receiving components communicating over a bus having first and second channels. The sending component may broadcast on the first channel a plurality of read and write address locations, a plurality of transfer qualifiers, and write data. The receiving component may store the write data broadcast on the first channel at the receiving component based on the write address locations and a first portion of the transfer qualifiers. The receiving component may also retrieve read data from the receiving component based on the read address locations and a second portion of the transfer qualifiers, and broadcast the retrieved read data on the second channel.

Abstract: A memory controller uses a throttling mechanism which estimates a throttling delay for achieving a target power consumption, and periodically blocks all memory commands for a number of clock cycles corresponding to the throttling delay. Idle memory ranks of the memory device are powered down while the memory commands are blocked. A regression model bases the throttling delay on a plurality of operating factors and a plurality of regression coefficients for the operating factors. In the illustrative implementation the operating factors include power consumption, a current number of bank conflicts, a current number of read commands, and a current number of write commands. Different sets of regression coefficients can be programmably stored for use with different system configurations.

Abstract: A method of controlling a clock frequency is disclosed and includes monitoring a plurality of master devices that are coupled to a bus within a system. The method also includes receiving an input from at least one of the plurality of master devices. The input can be a request an increase to the clock frequency of the bus. Further, the method includes selectively increasing the clock frequency of the bus in response to the request.

Abstract: Provided is a multiprocessor configured by stacking a plurality of unit chips each having, at least, a processor core and a memory, and the unit chip has a configuration including: a plurality of processor cores; a plurality of memories; a construction controlling unit setting connection relations between the processor core and the memory and between the processor core and the outside of the chip; and a chip connecting unit transmitting transaction between the processor, the memory, or the construction controlling unit and another stacked unit chip to be connected. The chip connecting units are arranged so as to be rotationally symmetric to each other on side portions of the unit chip, so that any of the unit chips configured by stacking is rotationally connected.

Abstract: A method of detecting master/slave response time-out under continuous packet format communications protocol, which calculates the time required for the slave device to respond to a Modbus request subject to Modbus TCP/UDP protocol. The method is to continuously send Modbus requests to a slave device through a detection device and to record each Modbus request sent time, and to have the slave device provide to the detection device a response for each Modbus request. By means of calculating the precise response time-out from the response time-outs which are gotten from the slave device responds to a predetermined number of Modbus requests, the user or manager can determine the response time-out required for the slave device precisely so as to give an EXECUTE instruction or command at the accurate time point.

Abstract: A method for operating a bus system, in particular in a microprocessor or microcontroller, and a semiconductor device for performing the method is disclosed. In one embodiment, for optimizing the order of accesses to the bus system, a method for operating a bus system includes at least one transmission channel, wherein the transmission channel connects at least two masters and at least one slave with one another. The masters are connected with an arbiter determining the order of accesses in which the masters access the transmission channel. The method provides that the arbiter takes into account meta information about planned accesses when determining the order of accesses. Meta information can further be stored and be referred to for subsequent determinations.

Abstract: Arbitration for a processor block core is described. Master devices are associated with a processor block core embedded in a host integrated circuit (“IC”). The master devices are coupled to core logic of the host IC via a crossbar switch and a bridge, which are part of the processor block core. The crossbar switch includes an arbiter. An arbitration protocol is selected from among a plurality of arbitration protocols for use by the arbiter. Pending transactions having are polled for access to the bridge for arbitration using the arbitration protocol selected.

Abstract: Embodiments of the present invention provide a media drive that is intended for reduction in power consumption required for serial communications to/from a host, and a power saving method thereof. In one embodiment, a HDD includes: a cache; a host interface for transferring, to a host, transfer data read out from the cache; a host interface manager that controls the execution of commands so as to generate a transfer unnecessary period during which a command and transfer data need not be exchanged with the host; and a MPU that brings a serial communication part of the host interface into a power save mode during the transfer unnecessary period. The host interface manager determines the optimum data transfer timing of transferring data from the cache to the host on the basis of a transfer rate at which data is transferred to the host, and a read rate at which data is read out from a disk into the cache.

Abstract: In an arbitration circuit in which a shared circuit such as a memory is used exclusively by one of a plurality of functional blocks at a time, an access reservation request is issued from one of the functional blocks, and the access request associated with the access reservation request is reserved. Thereafter, when an access request is issued from another functional block, it is determined which one of the access reservation request and the access request from these functional blocks takes precedence. For example, if the access request from the latter functional block has a low priority level, the access reservation request is selected and the circuit waits for an access request from the functional block which has issued this access reservation request. In this manner, it is possible to avoid cancellation of a once-accepted access request and waiting for a high-priority access request.

Abstract: An arbiter circuit includes a priority coefficient calculating unit, a priority coefficient comparator an acceptance determining unit, and a priority determining unit. The priority coefficient calculating unit calculates for each request an arbitration priority coefficient based on a priority level set for each request by requesters. The priority coefficient comparator compares arbitration priority coefficients calculated for the requesters by the priority coefficient calculating unit. The acceptance determining unit determines whether to accept the requests based on the comparison result by the priority coefficient comparator. When the arbitration priority coefficient calculated by the priority coefficient calculating unit is equal between two or more requests, the priority determining unit determines a priority order for accepting the requests.

Abstract: Cross-bar segment routing and access table address remapping functions are combined within a cross-bar of a system-on-a-chip. In this manner, address remapping may occur prior to segment routing. One or more access table caching registers may be included for each master port. The caching registers may allow for a rapid lookup of one or more access table entries associated with each master, as well as allow for the simultaneous lookup by multiple masters without adding ports to the access table. A segment identifier may be stored in the caching registers to indicate how to route a matching request to the appropriate slave segment.

Abstract: A bridge for translating a first storage protocol to a second protocol includes an affiliation manager. The affiliation manager accepts a connection from a host and establishes a connection between a device that uses the second protocol and the host that uses the second protocol. The affiliation manager monitors commands received from the host and responses received from the device on the connection. Upon detecting no pending commands for the device, the bridge may close the connection to the host if there is another host requesting a new connection to the device and establish the new connection between the device and the other host.

Abstract: Embodiments of the invention relate to a driven-frequency processor core. It comprises at least one processor, a non-volatile memory comprising a startup program, a bridge interconnecting buses linking the various components of said processor core, an interface component. The non-volatile memory comprises at least two frequency-related configurations each corresponding to an operating mode of the buses and/or of the components of said processor core. The non-volatile memory comprises an item of information which makes it possible to determine which operating mode should be used, said item of information being read by the interface component so as to determine the chosen mode. The interface component generates one or more clock signals, the frequency of said generated clock signals corresponding substantially to that described by the configuration of the chosen mode. The clock signals drive the buses and/or the components of said processor core.

Abstract: A data processing device with an efficient mechanism for controlling bus priority of multiple processors. The device has a data memory that is accessible to the processors via each processor's individual control bus and a common control bus. A bus selector is disposed between the individual control buses and the common control bus and controlled by a bus arbiter that resolves bus requests on the individual control buses from the processors attempting access to the data memory. The bus arbiter sends a selection command to the bus selector, thereby permitting a specified processor to reach the data memory. A bus monitor counts bus requests and conflicts between them, determines priority of each processor attempting access to the data memory according to the count results, and sends a wait command signal to low-priority processors so as to delay their access to the data memory.

Abstract: A method of processing J1850 requests using a scan tool having multiple processor systems is provided. The scan tool includes a first processor that processes data according to scan tool functions to assist with diagnosing and repairing a vehicle. A second processor receives data transmitted to the first processor and stores the data in a buffer. The second processor determines whether the data is complete to enable the first processor to make a determination regarding the data.

Abstract: A USB device may be simultaneously configured and accessed by two or more USB hosts. The USB device may include separate upstream ports and buffers for each host, and a multi-host capable device controller configured to respond to simultaneous USB requests received from more than one host. The USB device may maintain a dedicated address, configuration, and response information for each host. The USB device may include a shared USB function block, and a multi-host controller configured to establish concurrent respective USB connections between the shared USB function block and two or more USB hosts, to allow the two or more USB hosts to simultaneously configure the USB device for the shared USB function. The multi-host controller may be configured to receive and respond to simultaneous respective USB access requests for the shared USB function sent by the two or more USB hosts.

Abstract: A system including a south bridge, a first processor connected to the south bridge, and a second processor connected to the south bridge. The system further includes at least one device connected to the south bridge, and a resource manager coupled to the south bridge that allocates use of the at least one device between the first processor and the second processor.

Abstract: The present computing system using PCI-E architecture includes at least one first PCI-E port, a first port-arbiter, a first URD logic, a microprocessor, a DARD logic and a device arbiter. The first port-arbiter receives a data from the first PCI-E port. The first URD logic is coupled to said first port-arbiter. The first URD logic includes an onboard range table and a PCI-E device range table for detecting the data of onboard access or peer-to-peer access. The microprocessor receives and processes the data from the first URD logic for said onboard access. The DARD logic receives the data from the microprocessor. The DARD logic decodes a device range of a downstream request of the data. The device arbiter is coupled to the DARD logic and the first URD logic for dispatching the data to one of the first PCI-E port.

Abstract: In one embodiment, the present invention includes a bus controller including a mutual exclusion unit to receive a data transmission request from first and second agents and to select one of the agents for servicing based on which agent is the first to send the request, multiple selection units controlled by the mutual exclusion unit, and a two-phase register coupled to at least one of the selection units to transmit data from the selected agent. Other embodiments are described and claimed.

Abstract: A system for dynamically allocating buffers between components in a computer system is described. The system uses matched sets of bi-directional buffers to control data flow between the processor and the computer bus. The dynamic buffer allocation system allows simultaneous data transfer from the processor to the buffers, and from the buffers to the computer bus.

Abstract: A method for pipeline arbitration including receiving a first request for a shared chip interface from a first pipeline, determining whether a response bus of the shared chip interface is needed by the first request, and if it is determined that the response bus is not needed by the first request, concluding that the first request needs just an address bus of the shared chip interface, arbitrating the first request with a second request for the shared chip interface received from a second pipeline for access to the address bus, sending the first request to the address bus if the first request wins the arbitration over the second request, and rejecting the first request if the second request wins the arbitration over the first request. A corresponding system and computer program product.

Abstract: A data flow management system and method in which the application and its clients are made aware of the available credits for each type of transfer before the transfer is attempted. This enables the clients to transmit packets only when the RX side has issued a sufficient number of credits to insure that the transmission will not be stalled. The invention eliminates the need for FIFO buffers in the PCI-Express core, since the application will not transmit packets to the core until the required number of credits for the particular transfer type is available. Therefore, packet transmissions do not require buffering in the core, as they are only sent when they can be sent all the way through the core to the link.

Abstract: The present invention offers a daisy chain serial bus system. For bus construction, the slave device has a first data transmission port to transfer serial data with its upward connected device and a second data transmission port to transfer serial data with its downward connected device. The most upward slave device is connected to a master device. In each slave device, the input data from a first data transmission port is transferred to a data input gate in a second data transmission port. There is a control register in each slave device to control the data input gate of the second data transmission port. After the bus system has been started, only the slave device connected to the master device can receive the data from the master device, so that the master device can assign the first device address to the slave device connected to it, then, the master device can assign the second device address to the slave device next connected to the first slave device on the bus.

Abstract: An apparatus and method for connecting a processor to buses. The apparatus includes a multiplexer which, when addressing information indicating the address of a first memory connected to a synchronous data bus synchronized with a processor, from the processor is received, receives first data from the processor and transfers the received first data to the first memory through the synchronous data bus, or receives second data from the first memory through the synchronous data bus and transfers the received second data to the processor, and if address information indicating the address of a second memory connected to an asynchronous data bus not synchronized with the processor, from the processor is received, receives third data from the processor and transfers the third data to a buffer, or receives fourth data from the buffer and transfers the fourth data to the processor.

Abstract: A bus bridge is connected to a primary bus and a secondary bus, and relays data between a master and a target which are each connected to a different one of the primary and secondary buses. The bus bridge includes a primary bus interface, a secondary bus interface, a data FIFO, and a register block. The register block, which can be written by the master, includes two registers corresponding to the primary and secondary buses. Relay information showing the number of entries of data to be relayed from the target to the master is registered in a register corresponding to a bus to which the target is connected. In a read transaction, the primary bus interface or the secondary bus interface reads data from the target until data of the amount shown by the registered relay information is stored in the data FIFO.

Abstract: An IO processor includes an embedded central processing unit (CPU), a switch connected to the embedded CPU, an external CPU bus controller connected to the switch for optionally connecting to an external CPU, a first memory controller connected to the switch for connecting to a first memory, and a second memory controller connected to the switch for optionally connecting to a second memory. The IO processor may be connected to the external CPU, to the second memory, or be capable of connecting to external CPUs of different ranks, depending on the situation, so as to meet the cost considerations and the actual application requirements.

Abstract: A PCI bridge device includes an arbiter that uses state information comprised of knowledge of the bus protocol and a history of recent transactions to predict the type of transaction a requestor will issue. The prediction is then used as a basis to mask or allow bus requests from the requester. The arbiter does not grant access to devices that will predictably issue transactions that do not result in the transfer of data. This approach can decrease time wasted by devices attempting unsuccessful transactions and can provide a commensurate increase in bus utilization. The overall effect is an increase in average bus bandwidth and a decrease in average data transfer latencies.

Abstract: A central processor unit (CPU) is connected to a system/graphics controller generally comprising a monolithic semiconductor device. The system/graphics controller is connected to an input output (IO) controller via a high-speed PCI bus. The IO controller interfaces to the system graphics controller via the high-speed PCI bus. The IO controller includes a lower speed PCI port controlled by an arbiter within the IO controller. Generally, the low speed PCI arbiter of the IO controller will interface to standard 33 MHz PCI cards. In addition, the IO controller interfaces to an external storage device, such as a hard drive, via either a standard or a proprietary bus protocol. A unified system/graphics memory which is accessed by the system/graphics controller. The unified memory contains both system data and graphics data. In a specific embodiment, two channels, CH0 and CH1 access the unified memory.

Abstract: PCI Express bus utilization is monitored for one or more predetermined thresholds to adjust the width of the bus in accordance with the utilization to provide power savings with minimal impact on performance. For instance, a performance monitor of a graphics controller tracks bus utilization with registers to adjust bus width between one, eight and sixteen lanes. Reduced numbers of active lanes are used at low utilization, such as one lane when a desktop graphic is presented on the display, increased numbers of active lanes are used at moderate utilization, such as eight lanes when a video image is presented on the display, and all lanes are active at high utilization, such as for presentation of three dimensional images.

Abstract: Systems and methods of power management provide for issuing a power saving message from a processor toward a controller and using the controller to conduct a power saving activity in response to the power saving message. In one embodiment, the power saving message is issued by de-asserting a bus arbitration signal and the power saving activity can include disabling one or more input buffers of the controller.

Abstract: Method and apparatus for arbitrating prioritized cycle streams in a manner that prevents starvation. High priority and low priority arbitration pools are employed for arbitrating multiple input cycle streams. Each cycle stream contains a stream of requests of a given type and associated priority. Under normal circumstances in which resource buffer availability for a destination device is not an issue, higher priority streams are provided grants over lower priority streams, with all streams receiving grants. However, when a resource buffer is not available for a lower priority stream, arbitration of high priority streams with available buffer resources are redirected to the low priority arbitration pool, resulting in generation of grant counts for both the higher and lower priority streams.

Abstract: A USB device may be simultaneously configured and accessed by two or more USB hosts. The USB device may include separate upstream ports and buffers for each host, and a multi-host capable device controller configured to respond to simultaneous USB requests received from more than one host. The USB device may maintain a dedicated address, configuration, and response information for each host. The USB device may include a shared USB function block, and a multi-host controller configured to establish concurrent respective USB connections between the shared USB function block and two or more USB hosts, to allow the two or more USB hosts to simultaneously configure the USB device for the shared USB function. The multi-host controller may be configured to receive and respond to simultaneous respective USB access requests for the shared USB function sent by the two or more USB hosts.

Abstract: A shared USB device may be simultaneously configured and accessed by two or more USB hosts by using a multi-host capable device controller. The multi-host capable device may include separate upstream ports and buffers for each host, and may be configured with the capability to respond to USB requests from more than one host. The multi-host capable device may maintain a dedicated address, configuration, and response information for each host. Each host may therefore establish a dedicated USB connection with the sharing device without the sharing device having to be re-configured or re-enumerated each and every time the upstream hosts alternate accessing the USB device.

Abstract: A pulsed arbitration system has a partial-address coincidence detector with a partial-address collision flag as an output. An active global word line detector and disable pulse generator receives the partial-address collision flag as well as a decoded row address and an internal write pulse as an input, and generates a disable pulse for the interfering global word line of the colliding reading port.

Abstract: A queued interface device configured to communicate with a peripheral includes a first interface configured to receive and store a first set of peripheral requests from a first core, a second interface configured to receive and store a second set of peripheral requests from a second core, and an arbitrator coupled to the first interface and the second interface. The arbitrator, which may include multiple sets of registers to store the peripheral requests, is configured to selectively send the first set of peripheral requests and the second set of peripheral requests to the peripheral. The peripheral simultaneously appears as a dedicated peripheral for both the first and second cores.

Abstract: A distributed direct memory access (DMA) method, apparatus, and system is provided within a system on chip (SOC). DMA controller units are distributed to various functional modules desiring direct memory access. The functional modules interface to a systems bus over which the direct memory access occurs. A global buffer memory, to which the direct memory access is desired, is coupled to the system bus. Bus arbitrators are utilized to arbitrate which functional modules have access to the system bus to perform the direct memory access. Once a functional module is selected by the bus arbitrator to have access to the system bus, it can establish a DMA routine with the global buffer memory.