摘要:
A circuit-based digital communications network is provided for a large data center environment that utilizes circuit switching in lieu of packet switching in order to lower the cost of the network and to gain performance efficiencies. A method for transmitting data in such a network comprises sending a setup request for a path for transmitting the data to a destination node and then speculatively sending the data to the destination node before the setup request is completed.
摘要:
A circuit-based digital communications network is provided for a large data center environment that utilizes circuit switching in lieu of packet switching in order to lower the cost of the network and to gain performance efficiencies. A method for transmitting data in such a network comprises sending a setup request for a path for transmitting the data to a destination node and then speculatively sending the data to the destination node before the setup request is completed.
摘要:
Optical user input technology comprises three-dimensional (3D) input sensors and 3D location emitters to enable high-precision input in a 3D space, and the 3D location emitter may be a stylus or other writing or pointing device. Certain implementations may comprise an orientation assembly for transmitting orientation of the 3D location emitter in addition to location within a 3D space, and some implementations may also use selectively identifiable signaling from the 3D location emitters to the 3D input sensors to distinguish one 3D location emitter from another, to transmit data other data from a 3D location emitter to a 3D location sensor, or as a means of providing orientation information for the 3D location emitter with respect to the 3D location sensor. Also disclosed are position fixing, indoor navigation, and other complementary applications using 3D input sensors and/or 3D location emitters.
摘要:
Optical user input technology comprises three-dimensional (3D) input sensors and 3D location emitters to enable high-precision input in a 3D space, and the 3D location emitter may be a stylus or other writing or pointing device. Certain implementations may comprise an orientation assembly for transmitting orientation of the 3D location emitter in addition to location within a 3D space, and some implementations may also use selectively identifiable signaling from the 3D location emitters to the 3D input sensors to distinguish one 3D location emitter from another, to transmit data other data from a 3D location emitter to a 3D location sensor, or as a means of providing orientation information for the 3D location emitter with respect to the 3D location sensor. Also disclosed are position fixing, indoor navigation, and other complementary applications using 3D input sensors and/or 3D location emitters.
摘要:
A mesh connected local area network provides automatic packet switching and routing between host computers coupled to the network. The network has a multiplicity of cut-through, nonblocking switches, each capable of simultaneously routing a multiplicity of data packets. Low host-to-host latency is achieved through the use of cut-through switches with separate internal buffers for each packet being routed. The switches are interconnected with one another and are coupled to the host computers of the network by point to point full duplex links. While each switch can be coupled to ten or more network members, i.e., switches and hosts, each link is coupled to only two network members and is dedicated to carrying signals therebetween. Whenever a new switch or link is added to the network, and whenever a switch or link fails, the switches in the network automatically reconfigure the network by recomputing the set of legal paths through the network.
摘要:
A system and method are provided for reducing a potential thief's motivation to steal an electronic device, by rendering the device inoperative at some time after it is stolen. The mechanism used to deter theft may include a modified primary integrated circuit chip in the electronic device, such as the central processing unit (CPU), a memory controller chip, or a primary input/output (I/O) chip. The chip may be important enough to the normal operation of the electronic device such that without normal operation of the chip, the electronic device also would not operate normally, thus rendering the electronic device partially or fully disabled. A “recharger” device may be used to recharge, or reset the operability of the chip.
摘要:
In a multiprocessor computer system, a number of processors are coupled to main memory by a shared memory bus, and one or more of the processors have a two level direct mapped cache memory. When any one processor updates data in a shared portion of the address space, a cache check request signal is transmitted on the shared data bus, which enables all the cache memories to update their contents if necessary. Since both caches are direct mapped, each line of data stored in the first cache is also stored in one of the blocks in the second cache. Each cache has control logic for determining when a specified address location is stored in one of its lines or blocks. To avoid spurious accesses to the first level cache when a cache check is performed, the second cache has a special table which stores a pointer for each line in said first cache array. This pointer denotes the block in the second cache which stores the same data as is stored in the corresponding line of the first cache. When the control logic of the second cache indicates that the specified address for a cache check is located in the second cache, a lookup circuit compares the pointer in the special table which corresponds to the specified address with a subset of the bits of the specified address. If the two match, then the specified address is located in the first cache, and the first cache is updated.
摘要:
In a data processing system having a plurality of commander nodes and at least one resource node interconnected by a system bus, a bus arbitration technique determines which commander node is to gain control of the system bus to access the resource node. The bus arbitration technique assigns priority levels to all commander nodes, with at least one commander node receiving more than one priority level. Each priority level has an associated signal path. During each arbitration, each contending commander node can activate or assert the signal path associated with its priority level, and the commander node having more than one priority level can assert the signal path associated with any one of its priority levels. All commander nodes monitor all the signal paths to determine the identity of the contending commander node that asserted the signal path associated with the highest priority level among those that were asserted, and, thus, the contending commander node that "won" the arbitration.
摘要:
In a data processing system in which resource units are shared by a plurality of processing units, an arbitration unit is disclosed wherein the priority assigned to each processing unit is dynamically assigned to equalize accessibility to the shared resource. A signal path, associated with each possible level of priority, is coupled to each processor unit. The processor unit applies an activation signal to the signal line associated with the priority of the processing unit when the processing unit has a requirement for the shared resource and an arbitration is being performed to determine access to the resource. During the arbitration procedure, each processing unit requiring access to the shared resource compares the current priority of the associated processing unit to the activation signals on the signal paths to determine when the processing unit can gain access to the shared resource. After the arbitration procedure, the processing unit priority level is redetermined by each processing unit based on a comparison of the current priority level and the highest priority level active during arbitration.
摘要:
A data processing system includes a disk drive, a disk drive controller, a main memory and a CPU. The main memory has disk command data stored therein in a chain of disk command blocks (DCB's). Each DCB contains a first word pointing to the next DCB in the chain, a second word containing status information and a third word containing command information. A portion of the command word contains a predetermined verification word when the DCB is valid. The CPU includes means for comparing this portion with the predetermined verification word as stored in a constant memory. If the two correspond, the DCB is valid. Each DCB also includes a fourth word pointing to a block of main memory in which header data is stored. Header data defines the address of the recording location of the disk. A fifth word points to a block of main memory in which label data is stored. Label data defines the name and/or number of the file, as well as itself including a pointer to the address location on the disk at which the next page of the file data is stored. A sixth word of the DCB points to a block of main memory in which the associated page of file data is stored. A seventh word specifies the recording location on the disk (drive, track, sector) where the actions specified in the command word are to be carried out. Each such recording location is capable of having stored therein the header, label and file data associated with a specific DCB.