Abstract: A device and a method detect an acceleration of a logic signal expressed by a closeness, beyond a closeness threshold, of at least two variation edges of the logic signal. A first control bit and a second control bit are provided. At each edge of the logic signal, the value of the first control bit is inverted after a first delay and the value of the second control bit is inverted after a second delay. An acceleration is detected when the two control bits have at the same time their respective initial values or their respective inverted initial values. Application is in particular but not exclusively to the detection of error injections in a secured integrated circuit.

Abstract: Systems, controllers, and methods are disclosed, such as an initialization system including a controller configured to receive patterns of read data coupled from a memory device through a plurality of read data lanes. The controller is operable to detect lane-to-lane skew in the patterns of read data. The controller then adjusts the manner in which the read data received through the read data lanes during normal operation are divided into frames. The controller can also couple patterns of command/address bits to the memory device through a plurality of command/address lanes. The memory device can send the received command/address bits back to the controller through the read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of command/address bits received through the read data lanes to adjust the manner in which the command/address bits coupled through the command/address lanes during normal operation are divided into frames.

Abstract: A communication system includes a synchronizing signal generator that generates a synchronizing signal based on a timing of an alternating waveform in a power line, a data communicating circuit that performs the data communication, and a communication controller that controls to acquire a transmitting right utilizing a timing of the synchronizing signal and to control the communication circuit in accordance with whether or not the communication apparatus acquires the transmitting right.

Abstract: Scheduler 304 performs scheduling such that the communication terminal apparatuses to transmit packets to are determined according to the order in CIR information output from demodulator 303, and determines the modulation schemes and coding rates of the packets. Command detector 305 detects an ARQ command transmitted from the communication terminal apparatus determined in scheduler 304, outputs an ACK/NACK signals to buffer 306, and outputs a SUSUPEND signal or a GIVEUP signal to scheduler 304. Scheduler 304 stops retransmission upon receiving a SUSPEND signal or a GIVEUP signal from command detector 305, and redoes the scheduling. Thus, it is possible to improve overall system throughput in a wireless communication system that performs packet transmission.

Abstract: An information communication terminal performs communications with another information communication terminal over a radio communication network system. In the information communication terminal, a receiving unit receives an externally transmitted frame. In a state where error correction is to be performed, a correction processing unit outputs data after performing error correction according to correction information in the frame on data in the frame received by the receiving unit. In a state where the error correction is not to be performed, the correction processing unit outputs the data without performing the error correction on the data in the frame received by the receiving unit. A determining unit determines whether the error correction is to be performed by the correction processing unit or not.

Abstract: An apparatus, method and computer program operable in a network controls consistency guarantees of a plurality of data copies in a storage apparatus, and includes: a lease control component for extending a lease to the storage apparatus; and a consistency freeze/thaw component responsive to a failure indication for initiating a consistency freeze action at the storage apparatus prior to expiration of the current group lease period. It may further include a timer component for waiting the apparatus for a predetermined period after the consistency freeze action, where the consistency freeze/thaw component is operable to initiate a thaw action at the storage apparatus.

Abstract: A test and measurement instrument including an input configured to receive a signal and output digitized data; a memory configured to store reference digitized data including a reference sequence; a pattern detector configured to detect the reference sequence in the digitized data and generate a synchronization signal in response; a memory controller configured to cause the memory to output the reference digitized data in response to the synchronization signal; and a comparator configured to compare the reference digitized data output from the memory to the digitized data.

Abstract: In a method and a device for decoding a signal, the signal is transmitted via at least one connecting line of a data transmission system, in a user of the data transmission system receiving the signal. It is provided to measure the interval of a change—provided compulsorily in a transmission protocol used in the data transmission system—of the signal from rising to falling or from falling to rising edge. A tendency for an asymmetrical delay of the signal can be ascertained from the measured interval. The sampling of the bits of the received signal can be improved as a function of the interval or of the asymmetrical delay, for example, by setting the sampling instant in variable fashion. Alternatively, the interval or the asymmetrical delay can be utilized for diagnostic purposes.

Abstract: An RDS compatible receiver has a demodulator which demodulates RDS data, a register which converts the demodulated RDS data to block data and outputs the block data, an offset generating unit which predicts and outputs an offset word of the block data based on values of a pattern match flag signal and a synchronization flag signal, an error correction processing unit which performs error correction of the block data using the predicted offset word, compares the number of error corrections with a predetermined correction threshold, determines whether the predicted offset word is right or not based on the comparison result, and outputs the pattern match flag signal based on the determination result, and a synchronization determining unit which detects whether or not the predicted offset word determined to be right matches a predetermined offset sequence pattern, determines whether RDS block synchronization is established or not, and outputs the synchronization flag signal based on the determination result.

Abstract: A burst mode receiver including a CDR circuit that does not perform bit synchronization determination at a wrong position even when a burst signal waveform containing a distortion is input is provided. The burst mode receiver includes a CDR circuit for reproducing clock and data from a received signal, a bit synchronization determination circuit for determining whether the CDR circuit is in an optimum phase, a waveform distortion determination circuit for determining from the received signal whether there is waveform distortion, and a CDR output enable determination circuit for determining whether an output of the CDR circuit is valid or invalid. The CDR output enable determination circuit performs CDR output enable determination based on a bit synchronization determination result and a waveform distortion determination result.

Abstract: A clock and data recovery device receives a serial data stream and produces recovered clock and data signals. The clock and data recovery device operates over a range of frequencies and without use an external reference clock. A first loop supplies a first clock signal to a second loop. The second loop modifies the first clock signal to produce the recovered clock signal and uses the recover clock signal to produce the recovered data signal. The first loop changes the frequency of the first clock signal based on frequency comparison and data transition density metrics.

Abstract: A device for controlling frequency synchronization includes a processor (101) for controlling a phase-controlled clock signal to achieve phase-locking between the phase-controlled clock signal and a reference clock signal, and for controlling a frequency-controlled clock signal so as to achieve frequency-locking between the frequency-controlled clock signal and the reference clock signal. The processor is also configured to monitor a deviation between the frequency- and phase-controlled clock signals, detect a change of circumstances such as temperature changes causing frequency drifting of the frequency-controlled clock signal, and replace or correct the frequency-controlled clock signal with or on the basis of the phase-controlled clock signal when both the monitored deviation and the detected change of circumstances show correlation confirming frequency drift of the frequency-controlled clock signal.

Abstract: In operation, a transmitting device selects a synchronization pattern associated with the desired timeslot that is at least mutually exclusive from synchronization patterns associated with other timeslots on the same frequency in the system. Once selected, the transmitting device transmits a burst embedding the synchronization pattern that was selected, where appropriate. If the receiving device detects the synchronization pattern, it immediately synchronizes with the timeslot with confidence that it is synchronizing to the desired timeslot by using sets of synchronization patterns associated with the desired timeslot that are at least mutually exclusive from synchronization patterns associated with the other timeslots on the same frequency.

Abstract: Methods and apparatus are provided for pseudo asynchronous testing of receive paths in serializer/deserializer (SerDes) devices. A SerDes device is tested by applying a source of serial data to a receive path of the SerDes device during a test mode. The receive path substantially aligns to incoming data using a bit clock. A phase is adjusted during the test mode of the bit clock relative to the source of serial data to evaluate the SerDes device. The source of serial data may be, for example, a reference clock used by a phase locked loop to generate the bit clock. The phase of the bit clock can be directly controlled during the test mode, for example, by a test phase control signal, such as a plurality of interpolation codes that are applied to an interpolator that alters a phase of the bit clock.

Abstract: An apparatus for transferring data in a non-spread domain to a spread domain. The apparatus comprises a first-in-first-out (FIFO) memory; a write pointer generator adapted to generate a write pointer for writing data into the FIFO memory in response to a non-spread clock signal; a spread-clock generator adapted to generate a spread clock signal based on the non-spread clock signal; a read pointer generator adapted to generate a read pointer for reading data from the FIFO memory in response to the spread clock signal; and a controller adapted to control the spread-clock generator in response to the read and write pointers indicating predetermined potential data overflow or underflow of the FIFO memory.

Abstract: A video receiving apparatus includes a receiving unit, a detecting unit, a determining unit, and a control unit. The receiving unit receives a video stream transmitted from a video distribution apparatus and to be reproduced by a video reproducing unit. The detecting unit detects an error occurrence position on the video stream in response to an error occurring during receiving of the video stream. The determining unit determines a reproduction start time based on the error occurrence position detected by the detecting unit and a position of a predetermined synchronization code in the video stream so that reproduction of the video stream is started before the error occurrence position. The control unit transmits a reproduction request including the determined reproduction start time to the video distribution apparatus.

Abstract: A differential transmitter and an auto-adjustment method of data strobe thereof are provided. The differential transmitter includes a phase-detecting unit, a switching unit, a rising edge strobe unit, and a falling edge strobe unit. The phase-detecting unit detects a phase relation between a clock signal and a data signal to outputs a detection result. The rising edge strobe unit latches the data signal at a rising edge of the clock signal, and converts a latching result to a first differential output signal. The falling-edge-strobe unit latches the data signal at a falling edge of the clock signal, and converts a latching result to a second differential output signal. The switching unit determines whether to switch the clock signal and data signal to the rising edge strobe unit or to the falling edge strobe unit according to the detection result.

Abstract: A unified filter bank for performing signal conversions may include an interface that receives signal conversion commands in relation to multiple types of compressed audio bitstreams. The unified filter bank may also include a reconfigurable transform component that performs a transform as part of signal conversion for the multiple types of compressed audio bitstreams. The unified filter bank may also include complementary modules that perform complementary processing as part of the signal conversion for the multiple types of compressed audio bitstreams. The unified filter bank may also include an interface command controller that controls the configuration of the reconfigurable transform component and the complementary modules.

Abstract: Systems, controllers and methods are disclosed, such as an initialization system including a controller that receives patterns of read data coupled from a memory device through a plurality of read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of read data received through the read data lanes. The controller then adjusts the manner in which the read data received through the read data lanes during normal operation are divided into frames. The controller can also couple patterns of command/address bits to the memory device through a plurality of command/address lanes. The memory device can send the received command/address bits back to the controller through the read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of command/address bits received through the read data lanes to adjust the manner in which the command/address bits coupled through the command/address lanes during normal operation are divided into frames.

Abstract: Methods and apparatus are provided for serializer/deserializer transmitter synchronization. A plurality of channels are synchronized in one or more serializer/deserializer devices by generating a synchronization request in one or more of the channels; generating an enable signal in response to the synchronization request; and generating a gated synchronization signal for only one or more periods of a synchronization signal in response to the enable signal. The gated synchronization signal can optionally be deasserted after the one or more periods of a synchronization signal.

Abstract: An advanced clock synchronization technique is adapted for use with a replication service in a data backup and recovery storage environment. The storage environment includes a plurality of source storage systems and target storage systems, wherein the source storage systems are illustratively embodied as source replication nodes. The advanced clock synchronization technique establishes a software-only, loosely-accurate global clock based on a timestamp and an associated error boundary. Notably, the timestamp and its error boundary are used as global clock information to enable synchronization (i.e., ordering of storage requests) among the source replication nodes and/or the target storage systems, thereby ensuring consistent replication of the storage requests on the target storage systems.

Abstract: The invention concerns a method for receiving a multi-carrier signal of reduced complexity when the number of carriers is not high. The method includes: demodulating the multi-carrier signal; converting a received signal received in binary representation into a modal representation in a base of at least two mutually prime numbers on a finite space of size equal to the product of the mutually prime numbers; demodulating including conversion.

Abstract: Methods and apparatus for gathering information about the eye of a high-speed serial data signal include sampling each bit of a repeating, multi-bit data pattern at several eye slice locations. For any given eye slice location, each bit in the data pattern is compared in voltage to a base line reference signal voltage to establish a reference value for that bit. Then the reference signal voltage is gradually increased while the voltage comparisons are repeated until for some bit a result of the comparing is different than the reference value for that bit. This establishes an upper value for the eye at the eye slice location. The reference signal voltage is then gradually decreased to similarly find a lower value for that eye slice.

Abstract: Methods and apparatus for determining at least part of the width of the eye of a high-speed serial data signal use clock and data recovery circuitry operating on that signal to produce a first clock signal having a first phase relationship to the data signal. The first clock signal is used to produce a second clock signal whose phase can be controllably shifted relative to the first phase. The second clock signal is used to sample the data signal with different amounts of phase shift, e.g., until error checking circuitry detects that data errors in the resulting sample exceed an acceptable threshold for such errors. The amount(s) of phase shift that caused exceeding the threshold can be used as a basis for a measurement of eye width.

Abstract: Described are techniques executed in a data storage system in connection with processing an I/O request. The I/O request is received. It is determined whether the I/O request is a write request. If the I/O request is a write request, write request processing is performed. The write request processing includes: copying write request data of the write request to cache; destaging the write request data from the cache to a primary storage device; and copying, in accordance with a heuristic, the write request data from the primary storage device to an asynchronous mirror device including an asynchronous copy of data from the primary storage device, wherein the asynchronous mirror device is write disabled with respect to received write requests requesting to write data thereto, the asynchronous mirror device used for servicing data requested in connection with read requests upon the occurrence of a cache miss.

Abstract: Two data processing units having the same function, one of which is used for a master and the other for comparison, are provided, control of a circuit unit is performed by the master, the master data processing unit and the circuit unit are operated in synchronization with a first clock signal, the second data processing unit is operated in synchronization with a second clock signal having the same cycle and different phase from the first clock signal, and processing results of both the data processing units are compared in a comparison circuit. Flip flops are disposed on a signal path from the circuit unit to the comparison data processing unit and on a signal path from the master data processing unit to the comparator, and both the first and second clock signals are used for latch clocks of the flip flops in accordance with input signals thereof.

Abstract: A method, device, and system are disclosed. In one embodiment method includes determining a left edge and right edge of a valid data eye for a memory. The method continues by periodically checking the left and right edges for movement during operation of the memory. If movement is detected, the method retrains the valid data eye with an updated left edge and right edge.

Abstract: A method and system to facilitate a scalable scan system in the design of a system-on-chip. In one embodiment of the invention, the system-on-chip includes a controller and one or more clock gating units. The clock gating unit is added to each unique clock domain of each function or logic block in the system-on-chip. By having a controller that connects to each clock gating unit and the scan input and output signals in each logic block of the SOC, this allows a scalable scan system in the design of the SOC and allows frequent block level design changes in the SOC without extensive changes to the scan logic in one embodiment of the invention. In addition, the scalable scan system also allows at-speed scan write-through testing of a memory array that can improve the scan test coverage of the system-on-chip.

Abstract: An object of the present invention is to provide a semiconductor device capable of recognizing circuit malfunction in an actual operation and of specifying a point of the circuit malfunction, and the semiconductor device, which does not induce the malfunction in the circuit of a subsequent stage when restoring the malfunction. The present invention is the semiconductor device provided with a plurality of logic circuits and a plurality of judging circuits for judging malfunction based on data from the logic circuits, wherein each of the judging circuits is provided with a first register, delay unit, a second register, a comparator and scanning unit, which makes the second register a shift register to allow to transmit an error signal held in the second register to the subsequent stage, while allowing the comparator to hold a comparison result.

Abstract: A control circuit includes a plurality of shift register stages. Each shift register stage is capable of outputting an individual output signal. The output signal is utilized to be a driving signal of next shift register stages. Each shift register stage comprises a transistor for receiving a clear signal CLR. The residual charges of the shift register stage can be released when the clear signal CLR is in a high voltage level. The clear signal CLR is enabled during a non-blanking time of a liquid crystal display (LCD). Each current register stage can use an output signal of another shift register stage which is apart from the current shift register stage by a predetermined interval as the clear signal CLR. The clear signal CLR is used to release the residual charges of the shift register stage before the shift register stage outputs its own output signal.

Abstract: A semiconductor integrated circuit apparatus, comprising a data transmitter circuit, and a plurality of data receiver circuits each having a data converter circuit which restores each of bits of identification number data and transfer data from a shift register of the data transmitter circuit to 2-bit complementary data transmitted via first and second transmission lines, a reception control circuit which, when a transfer completion signal has been received via a third transmission line, compares an allocated identification number with the restored identification number data, and a shift register provided in association with the reception control circuit, wherein each reception control circuit feeds transfer data transmitted from the data transmitter circuit corresponding to the identification number data to the associated shift register in accordance with a result of comparison between the identification number data and the allocated identification number.

Abstract: For an error rate QBER, threshold values are preset, including a threshold value Qbit for frame synchronization processing, a threshold value Qphase for phase correction processing, and a threshold value QEve for eavesdropping detection. Upon the distribution of a quantum key from a sender to a receiver, when the measurement value of QBER is deteriorated more than Qbit, frame synchronization processing is performed. When the measurement value of QBER is deteriorated more than Qphase, phase correction processing and frame synchronization processing are performed. When QBER does not become better than QEve even after these recovery-processing steps are repeated N times, it is determined that there is a possibility of eavesdropping, and the processing is stopped.

Abstract: A circuit verifying method is provided for a logic circuit of a first sequential circuit which outputs a first data based on an input data in synchronization with a first clock signal, and a second sequential circuit which outputs a second data based on the first data in synchronization with a second clock signal with a period longer than that of a first clock signal. The circuit verifying method includes detecting a change of the input data in synchronization with the first clock signal; outputting a data indicating a meta stable state during a period longer than one period of the first clock signal based on the change of the input data as the first data; storing the changed input data in a storage unit based on the change of the input data; and outputting the changed input data which has been stored in the storage unit as the first data after stop the output of the data indicating the meta stable state.

Abstract: An object of the present invention is to provide a semiconductor device capable of recognizing circuit malfunction in an actual operation and of specifying a point of the circuit malfunction, and the semiconductor device, which does not induce the malfunction in the circuit of a subsequent stage when restoring the malfunction. The present invention is the semiconductor device provided with a plurality of logic circuits and a plurality of judging circuits for judging malfunction based on data from the logic circuits, wherein each of the judging circuits is provided with a first register, delay unit, a second register, a comparator and scanning unit, which makes the second register a shift register to allow to transmit an error signal held in the second register to the subsequent stage, while allowing the comparator to hold a comparison result.

Abstract: The invention concerns a circuit protected against transitory perturbations, comprising a combinatorial logic circuit (10), having at least an output (A); a circuit (20) generating an error control code for said output, and a storage element (24) provided at said output, controlled by the circuit generating a control code to be transparent when the control code is correct, and to maintain its status when the control code is incorrect.

Abstract: Systems, controllers and methods are disclosed, such as an initialization system including a controller that receives patterns of read data coupled from a memory device through a plurality of read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of read data received through the read data lanes. The controller then adjusts the manner in which the read data received through the read data lanes during normal operation are divided into frames. The controller can also couple patterns of command/address bits to the memory device through a plurality of command/address lanes. The memory device can send the received command/address bits back to the controller through the read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of command/address bits received through the read data lanes to adjust the manner in which the command/address bits coupled through the command/address lanes during normal operation are divided into frames.

Abstract: Two data processing units having the same function, one of which is used for a master and the other for comparison, are provided, control of a circuit unit is performed by the master, the master data processing unit and the circuit unit are operated in synchronization with a first clock signal, the second data processing unit is operated in synchronization with a second clock signal having the same cycle and different phase from the first clock signal, and processing results of both the data processing units are compared in a comparison circuit. Flip flops are disposed on a signal path from the circuit unit to the comparison data processing unit and on a signal path from the master data processing unit to the comparator, and both the first and second clock signals are used for latch clocks of the flip flops in accordance with input signals thereof.

Abstract: A system and method for measuring and correcting data lane skews uses a predefined datum within data streams transmitted on different data lanes to determine the fastest data lane and to compute relative data lane skew values for the data lanes with respect to the fastest data lane. The relative data lane skew values are then used to compensate for the data lane skews.

Abstract: An object of the present invention is to provide a semiconductor device capable of recognizing circuit malfunction in an actual operation and of specifying a point of the circuit malfunction, and the semiconductor device, which does not induce the malfunction in the circuit of a subsequent stage when restoring the malfunction. The present invention is the semiconductor device provided with a plurality of logic circuits and a plurality of judging circuits for judging malfunction based on data from the logic circuits, wherein each of the judging circuits is provided with a first register, delay unit, a second register, a comparator and scanning unit, which makes the second register a shift register to allow to transmit an error signal held in the second register to the subsequent stage, while allowing the comparator to hold a comparison result.

Abstract: Provided are a method and system for testing a semiconductor memory device using an internal clock signal of the semiconductor memory device as a data strobe signal. The internally-generated data strobe signal may be delayed to synchronize with test data. Because a test device need not supply the data strobe signal, the number of semiconductor memory modules that can be simultaneously tested can be increased, and an average test time for a unit memory module can be decreased.

Abstract: Provided is a test apparatus that tests a device under test, including a first pipeline that sequentially propagates pieces of pattern data included in a first test pattern, according to a first test period, and outputs the resulting data to the device under test; a second pipeline that sequentially propagates pieces of pattern data included in a second test pattern, according to a second test period that is different from the first test period, and outputs the resulting data to the device under test; a timing control section that controls at least one of a timing at which the first pipeline begins propagating a predetermined first pattern data and a timing at which the second pipeline begins propagating a predetermined second pattern data, based on the first test period and the second test period; and a judging section that judges pass/fail of the device under test based on a signal output by the device under test.

Abstract: A frame delineation mechanism which alternately considers even and odd sync pattern position possibilities. With the addition of toggle logic, each of 66 possible states of even and odd alignment are exhausted in turn, odd, followed by even, followed by odd and so on, providing synchronization more quickly than known mechanisms. Additionally, faster convergence is reached due to the use of an exhaust register which keeps track of those alignment states that were tested but did not provide synchronization. Until synchronization is acquired, the states indicated in the exhaust register are ignored in further attempts to acquire synchronization.

Abstract: Methods and apparatus provide for: a plurality of stages of combinational logic, each stage including a full latch circuit operable to transfer data into the given stage of combinational logic and a transparent latch circuit operable transfer output data from the given stage of combinational logic to a next of the stages; in each stage, passing state changes of output data from the given combinational logic irrespective of when such changes occur when a clock signal of the transparent latch circuit is at a first of two logic levels; and in each stage, withholding state changes of the output data until the clock signal of the transparent latch circuit transitions from the second of the two logic levels to the first logic level.

Abstract: A method and integrated circuit for LSSD testing. The integrated circuit includes a plurality of clock domains supplied with test clocks from separate clock generation circuits. In each clock domain, a scan latch at a clock domain boundary receiving an input from another clock domain includes a master latch for latching an input in response to a first clock, a slave latch for latching an output from the master latch in response to a second clock, a selector for supplying the master latch with a system input when the mode selection signal is at a second level, and a clock control circuit for turning off the first clock when the mode selection signal transits from the first level to the second level.

Abstract: A method for predicting performance of a radio link in a wireless communication terminal including hypothesizing a second codeword including information associated with a hypothesized first codeword, obtaining channel state information from a received signal, and estimating a decoder error rate of the first codeword under a condition that the second codeword may not be decoded correctly, wherein the decoder error rate is estimated using the channel state information.

Abstract: A testing circuit includes a signal generator operative to provide a control signal in response to a reference clock signal. The control signal may include both alignment and timing information operative to synchronize the timing and output of the signal generator with a device under test. A clock recovery instrument is electrically coupled to the signal generator. The clock recovery instrument generates the reference clock signal in response to a clock signal from the device under test. The reference clock signal is synchronized with the clock signal from the device under test such that signal generator operation is synchronized with the device under test independent of the behavior of the device under test.

Abstract: A semiconductor integrated circuit includes: an input/output cell that is included in a path captured during propagation delay testing and that has an output-stage buffer on an output bus; and a terminal connected to the output bus and an input bus of the input/output cell. An external load or a testing device is connectable to the terminal. The input/output cell has a switching part that is capable of switching between a first path that loops back at an output side of the output-stage buffer and a second path that loops back at an input side of the output-stage buffer. The first path is selected during normal operation and the second path is selected during the propagation delay testing.

Abstract: Systems and methods are disclosed herein to provide test features for integrated circuits. For example, in accordance with an embodiment of the present invention, an integrated circuit includes an input signal path adapted to route an address signal for a configurable memory. An input multiplexer, coupled to the input signal path, is controllable to route a first test signal provided via the input signal path for at least one memory configuration that does not use the input signal path for the address signal.

Abstract: Systems, controllers and methods are disclosed, such as an initialization system including a controller that receives patterns of read data coupled from a memory device through a plurality of read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of read data received through the read data lanes. The controller then adjusts the manner in which the read data received through the read data lanes during normal operation are divided into frames. The controller can also couple patterns of command/address bits to the memory device through a plurality of command/address lanes. The memory device can send the received command/address bits back to the controller through the read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of command/address bits received through the read data lanes to adjust the manner in which the command/address bits coupled through the command/address lanes during normal operation are divided into frames.

Abstract: A circuit for generating tracking error signal using differential phase detection, comprising a quadrant photodetector for receiving optical signal and inducting splitting signal A, splitting signal B, splitting signal C and splitting signal D, two adders for generating group signal (A+C) and group signal (B+D). A plurality of equalizers for receiving, equalizing and amplifying splitting signal A, splitting signal B, splitting signal C, splitting signal D, group signal (A+C) and group signal (B+D). A plurality of phase detectors for receiving the output of equalizers and comparing phase difference of splitting signal A and group signal (A+C), group signal (A+C) and splitting signal B, splitting signal C and group signal (B+D), and group signal (B+D) and splitting signal D, and outputting a plurality of adjustment signals respectively. A circuit for eliminating the phase difference by adding and subtracting some adjustment signals with same phase difference.