摘要:
A data processing system includes a mechanism to periodically idle the normal system operation to allow recalibration of its interface circuitry by transmission of data with transitions and logic levels indicative of actual operation. Provision is made to protect actual data of the system from corruption during recalibration.
摘要:
A method, apparatus, and computer instructions for managing a set of signal paths for a chip. A defective signal path within the set of signal paths for the chip is detected. Signals are re-routed through the set of signal paths such that the defective signal path is removed from the set of signal paths and sending signals using remaining data signal paths in the set of signal paths and using an extra signal path in response to detecting the defective signal path.
摘要:
An elastic interface apparatus and method are implemented. The elastic interface includes a plurality of storage units for storing for storing a stream of data values, wherein each storage unit sequentially stores members of respective sets of data values. Each data value is stored for a predetermined number of periods of a local clock. Selection circuitry may be coupled to the storage units to select the respective data value from the data stream for storage in the corresponding storage unit. Data is sequentially output from each storage unit in synchrony with the local clock on a target cycle of the local clock.
摘要:
An elastic interface apparatus and method are implemented. The elastic interface includes a plurality of storage units for storing for storing a stream of data values, wherein each storage unit sequentially stores members of respective sets of data values. Each data value is stored for a predetermined number of periods of a local clock. Selection circuitry may be coupled to the storage units to select the respective data value from the data stream for storage in the corresponding storage unit. Data is sequentially output from each storage unit in synchrony with the local clock on a target cycle of the local clock.
摘要:
A method and system for increasing speeds of transferring data in a data transfer system which includes a data source and data sink. Both the data source and data sink include clocks which are synchronized to a common clock frequency. A buffer is provided at the data sink and this buffer is utilized to received data from the data source. A control circuit is provided at the data sink and this control circuit receives a bus clock signal from the data source. An N segment dynamic shift register is provided within the data sink which includes at least two segments. A selectable shift control is provided for passing the data through an M segment subset of the N segment shift register, where M is less than N. Additionally, the length of the M segment subset is determined by the phase of a clock within the data sink at the time which the bus clock signal from the data source is received at the data sink. By selectively passing the data through an M segment subset of the N segment shift register, the data is accessible at the data sink at a controllable predetermined time.
摘要:
An inter-chip line transmission circuit in a transmitting chip and complementary receiving circuit in a receiving chip provide the capability to characterize the inter-chip interface by separately generating identical pseudo-random test data at both chips, comparing the data, and recording errors. Preferably, one or both chips can be tuned on an individual line basis to reduce errors by altering threshold detection voltage, signal delay, and/or driver power. The receiver circuit preferably contains counters for counting test cycles and errors, which can be masked for any particular line or type of error. A tunable and characterizable interface in accordance with the preferred embodiment thus supports the accurate determination of low error rates on an individual line basis for various tuning parameter settings.
摘要:
A method and apparatus are disclosed for communicating between a master and slave device. A sequence of data sets and a clock signal (“Bus clock”) are sent from the master to the slave, wherein the successive sets are asserted by the master at a certain frequency, each set being asserted for a certain time interval. The data and Bus clock are received by the slave, including capturing the data by the slave, responsive to the received Bus clock. The slave generates, from the received Bus clock, a clock (“Local clock”) for clocking operations on the slave. The sequence of the received data sets is held in a sequence of latches in the slave, each set being held for a time interval that is longer than the certain time interval for which the set was asserted by the master. The data sets are read in their respective sequence from the latches, responsive to the Local clock, so that the holding of respective data sets for the relatively longer time intervals in multiple latches and the reading of the data in sequence increases allowable skew of the Local clock relative to the received Bus clock.
摘要:
A phase detector for use in conjunction with a delay locked loop is provided. Programmable delay elements insert an adjustable delay in a received data stream. The programmable delays stress the setup and hold times of the incoming data. Phase detector sampling logic detects the phase difference between a nominal center of the data window, and the limits on the setup (early) edge of the data value window, and the hold time limit (late time) edge of the data valid window (“guardbands”). A data signal arriving earlier than an early guardband or later than a late guardband may not be correctly sampled, and a guardband failure may be said to have occurred. A state machine detects such guardband errors and provides corrective feedback signals.
摘要:
An apparatus and method for a dynamic wave-pipelined interface are implemented. Data signals received from a sending circuit delayed via a programmable delay device corresponding to each signal before being latched into the receiving device. The programmable delay in each delay device is set according to an initialization procedure whereby each signal is deskewed to a latest arriving signal. Additionally, a phase of an input/output (I/O) clock controlling the latching of the data signals is adjusted so that a latching transition is substantially centered in a data valid window.
摘要:
A method and circuitry for linearly delaying a signal with linear delay steps. In one embodiment, circuitry in an integrated circuit for linearly delaying a signal comprises a plurality of control signals. The circuitry further comprises a fine delay element coupled to at least one of the plurality of control signals where the fine delay element comprises logic circuitry configured to provide fine adjustments to the delay of the signal. The circuitry further comprises at least one course delay element coupled to the fine delay element where the at least one course delay element is coupled to at least one of the plurality of control signals. Furthermore, the at least one course delay element comprises logic circuitry configured to provide course adjustments to the delay of the signal. The circuitry for linearly delaying a signal is configured to provide testability and programmability. The circuitry for linearly delay a signal is configured to provide linear delay steps. In another embodiment of the present invention, a test signal is coupled to the fine delay element and to the at least one course delay element. The test signal is used to detect faults at the fine delay element and at the at least one course delay element. During the functional mode of this embodiment, power is reduced by disconnecting the test path during the functional mode.