Abstract: Methods and associated structure for realignment of returned read data from the memory component to the memory controller to adjust for phase shift in the memory device's supplied strobe signals due to propagation delays and other layout, fabrication and environmental factors. The realignment features of the present invention impose a calibrated delay on the memory controller's clock signal used to sample registered read data from the memory components. By so adjusting the alignment of returned read data with respect to the memory controller's clock, the present invention obviates the need for an asynchronous FIFO as is presently commonly practiced in the art to avoid such phase shifts between memory components and associated memory controller's.

Abstract: A slave device on a data bus has a register that stores a non-queued split master vector containing bits identifying whether a transaction with corresponding master devices have been split. An input gate is responsive to the status of the slave device and to receipt of a command from a master device when the slave device status is busy to set a bit in the non-queued split master vector identifying that the transaction with the corresponding master device is split. An output gate is responsive to a not busy status of the slave device to output the non-queued split master vector to the arbiter to re-arbitrate use of the data bus among the previously-split non-queued master devices.

Abstract: A memory controller for aligning write data and a clock strobe signal provided to a memory device includes a delay line coupled to a local clock input and providing as an output a delayed local clock signal. A first latch circuit receives data to be written to the memory device as an input and has an output coupled to a data input of the memory device. The first latch circuit is clocked by a first one of the local clock signal and the delayed local clock signal and provides in response the write data to the data input of the memory device. A clock strobe generating circuit is clocked by a second one of the local clock signal and the delayed local clock signal. The clock strobe generating circuit has an output coupled to a clock strobe input of the memory device and provides the clock strobe signal to the memory device.

Abstract: A slave device includes a queue that receives commands or data from a master device for execution on a first-in, first-out basis. A status register is responsive to the queue to provide a STATUS_FULL signal when the queue is full of commands and a STATUS_EMPTY signal when the queue is empty. A configuration register provides a DEBUG signal identifying a maintenance status of the slave device. A bus control provides a QUEUE_FULL signal in response to either (1) the STATUS_FULL signal or (2) the DEBUG signal and not the STATUS_EMPTY signal to split further commands or stall the data bus.

Abstract: A method an apparatus are provided for calibrating a mask signal which is used for masking a data strobe signal that is received from a memory device with read data. According to the method, one or more read operations are performed with the memory device, and the data strobe signal is sampled at a plurality of different time delays relative to a local clock signal to produce a plurality of data strobe sample values. The plurality of data strobe sample values are searched to identify a temporal location within a preamble phase of the data strobe sample values and one of the time delays that corresponds to the temporal location. A delay at which the mask signal is disabled in response to a read operation is then set relative to the local clock signal based on the time delay corresponding to the temporal location.

Abstract: A method and apparatus are provided for capturing data read from a memory device that is aligned with respect to a clock strobe signal originating from the memory device, which has constraints with respect to a local clock signal supplied to the memory device. The apparatus includes a circuit for capturing the data read from the memory device relative to the clock strobe signal to produce captured read data, a circuit for latching the captured read data relative to a sample clock signal, and a circuit for measuring a phase difference between the sample clock signal and the clock strobe signal and adjusting a phase of the sample clock signal as a function of the phase difference.

Abstract: A phase measurement circuit includes first and second complementary clock strobe inputs, a local clock input and a sample clock output. A programmable delay line is coupled between the local clock input and the sample clock output and has a plurality of propagation delay settings. First and second toggle circuits are clocked by the first and second clock strobe inputs, respectively, and each has a toggle output that changes state when clocked by the respective first or second clock strobe input. A capture latch circuit has first and second data inputs coupled to the toggle outputs of the first and second toggle circuits, respectively, has first and second capture outputs, and is clocked by the sample clock output. A synchronizer circuit has first and second data inputs coupled to the first and second capture outputs, respectively, has first and second synchronized capture outputs, and is clocked by the local clock input.

Abstract: A digital logic circuit, such as a FIFO memory, includes pointers, or indicators, generated in two clock domains, between which information is transferred, to indicate a location in the digital logic circuit for transferring the information into or out of the digital logic circuit within either clock domain. Each pointer is encoded with a “2-hot” encoded value within one of the clock domains. The 2-hot encoded value of each pointer is sent to the other clock domain to synchronize the pointer to the other clock domain as well as to its original clock domain. Within each clock domain, the pointer generated therein and the pointer received from the other clock domain are used to determine whether the information can be transferred into or out of the digital logic circuit.

Abstract: A digital logic circuit, such as a FIFO memory includes pointers, or indicators, generated in two clock domains, between which information is transferred, to indicate a location in the digital logic circuit for transferring the information into or out of the digital logic circuit within either clock domain. Each pointer is encoded with a “2-hot” encoded value within one of the clock domains. The 2-hot encoded value of each pointer is sent to the other clock domain to synchronize the pointer to the other clock domain as well as to its original clock domain. Within each clock domain, the pointer generated therein and the pointer received from the other clock domain are used to determine whether the information can be transferred into or out of the digital logic circuit.

Abstract: The invention relates in general to providing greater accuracy in scanning and digital reproduction of images. More specifically, the invention acts to improve the precision of optical data by substantially eliminating sensor drift or “dark current” and acts to improve the accuracy in identification of the position at which various optical samples are taken by determining and correcting for the lag time inherent in initiating and executing a sampling operation.

Abstract: A device for the distribution of liquid or dry particulate material, particularly for agricultural use. The device is adapted to be mounted upon a truck chassis or other device for movement in a direction of travel. The device includes a single hopper which may alternatively receive the liquid or particulate material. A dry feed mechanism is provided to remove the material from the tank to a metering station where the particulate material is subdivided. A plenum chamber is also provided to entrain each subdivision of particulate material for pneumatic conveyance within a distribution tube extending laterally of the direction of travel. The plenum chamber is aerodynamically curved such that the air velocity is substantially lateral upon entering the distribution tubes, increasing the air velocity in the tubes. The distribution tubes have exits which are laterally spaced to provide an even distribution of the particulate material.