Abstract: A memory controller includes an output buffer for receiving a clock signal and outputting the clock signal to an external memory; and a replica buffer for receiving the clock signal and outputting the clock signal to a counting circuit; wherein the replica buffer and the output buffer have the same delay time such that the clock signal received by the counting circuit can be synchronized with that received by the external memory, and therefore the counting circuit can accurately count to a predetermined time according to the clock signal and output an enabling signal to enable a data control signal. The present invention further provides a signal synchronizing method for the memory controller.

Abstract: A method for adjusting the working frequency of a chip is provided. The method detects a frequency adjustment range of a graphic chip when a system is booted. Then, an application program in full screen mode is executed, and a control hot key is enabled. Afterwards, an input of the control hot key is received to display a user interface. Finally, an input frequency inputted from the user interface is received, and the working frequency of the graphic chip is adjusted according to the input frequency in the frequency adjustment range. Therefore, even though the application program is executed in full screen mode, the working frequency of the graphic chip can still be adjusted according to requirements in any time, which is convenient for the user.

Abstract: A device may include a processor to execute a thread. The processor may be further configured to execute a set of wrappers that are called from within the thread to invoke a set of one-shot signal objects to generate delayed signals. Each of the set of wrappers may be configured to detect whether different ones of one-shot signal objects that were invoked from within the thread have generated signals at periodic time intervals, determine a delay to be used for invoking one of the set of one-shot signal objects, and invoke the one of the set of one-shot signal object to generate one of the delayed signals based on the delay when the different ones of one-shot signal objects have generated signals at periodic time intervals. The processor may be further configured to receive the delayed signals generated from the set of one-shot signal objects over a time period.

Abstract: Circuits for measuring a clock signal include a variable digital delay line that is configured to delay the clock signal by variable amounts in response to variable values of a digital control word that are applied thereto, to produce a variably delayed clock signal. A capture stage is responsive to the variably delayed clock signal and to the clock signal to capture a logic state of the variably delayed clock signal during transitions of the clock signal. A controller is configured to generate the variable values of the digital control word that are applied to the variable digital delay line and to identify a value of the digital control word in response to the capture stage capturing a change in the logic state of the variably delayed clock signal during a transition of the clock signal. Related methods and memory devices are also described.

Abstract: A first transfer circuit includes pipeline circuits having different number of stages, and switch circuits that exclusively supply the pipeline circuits with first and second read data. A second transfer circuit includes pipeline circuits having different number of stages, and switch circuits that exclusively supply the pipeline circuits with third and fourth read data. Outputs of the first and second transfer circuits are sequentially output from a multiplex circuit. When a first operation mode is selected, all the pipeline circuits are activated. When a second operation mode is selected, one of the pipeline circuits in the first transfer circuit and one of the pipeline circuits in the second transfer circuit are activated, whereas the others of the pipeline circuits are inactivated.

Abstract: In one embodiment, a system is configured to generate a time reference where the system includes a bi-directional loop configured to have a first propagation speed in a first direction and a second propagation speed in a second direction, wherein the first propagation speed is substantially equal to the second propagation speed. In one embodiment, the system further includes a plurality of system elements coupled to the bi-directional loop, wherein each respective system element of the plurality of system elements is configured to determine a time reference common to each as an average arrival time at the respective system element of a first signal transmitted in the first direction over the bi-directional loop and a second signal transmitted in the second direction over the bi-directional loop.

Abstract: The delay locked loop (“DLL”) delay interval can be locked to stop the DLL from wasting power in unnecessarily switching to synchronize the device with the DLL is associated to the system clock. This is achieved by adding logic sensing when a DRAM device will not imminently be called upon to output data and when the device has stabilized. Waiting for the DLL delay interval to stabilize before locking the delay interval still allows the DLL to immediately and effectively resume operations when the DLL is needed to synchronize the output of the DRAM device with the system clock. The DLL delay interval can be locked, together with the DLL clock, after the DRAM device is deselected by the chip select control line, after a number of no operation commands have been received, and/or after any command issued to the DRAM device has been completed.

Abstract: An apparatus and method is disclosed to compensate for skew and asymmetry of a locally processed system clock used to synchronize an output signal, e.g., a data signal or a timing signal, from a logic circuit, for example a memory device. A first phase detector, array of delay lock loop (DLL) delay elements and accompanying circuitry are disclosed to phase-lock the rising edge of the output signal with the rising edge of the system clock XCLK signal. Additionally, a comparator circuit, a register delay, an array of DLL delay elements and accompanying circuitry are disclosed to add or subtract delay from the falling edge of the DQ signal in order to produce a symmetrical output of the DQ signal.

Abstract: A method and multi-component electronic module device are provided that control the timing of output of data from a plurality of components on the multi-component module. One or more of the components are programmed to delay outputting data by a corresponding amount of time. In one embodiment, the one or more components are programmed such that all of the components output data at substantially the same time when they respond to a control signal. This is particularly useful for multi-component modules that are configured to respond to control signals in a so-called fly-by (or other) configuration that results in the control signal arriving at the components at different times causing the components to react to the control signal at different times.

Abstract: Redundant time-of-day (TOD) oscillators are aligned, within a master oscillator path, to local logic oscillator and used to create independent step-sync signals. A step checker validates and provides selection signals to identify which of the TOD oscillators operates according to a criterion. Independent step-sync signals are transmitted to several sibling chips. Local step and sync signals are delayed to arrive at TOD register nearly synchronous with TOD registers in sibling chips. A slave oscillator path may be used to select time signals generated in a sibling chip, whereby the master oscillator path is deselected. A primary control register set may be used to configure which among several chips is a master chip using the master oscillator path. All remaining chips are slave chips. All segments of the topology are redundant. One of multiple possible alternate topologies is defined in a secondary control register set.

Abstract: The present invention discloses a computer motherboard, which comprises: at least one memory module slot, a flash memory, a central processing unit socket; wherein, the memory module slot is used to plug at least one memory module; the flash memory is used to store BIOS programming codes, in which the BIOS programming codes are provided with at least one memory configuration programming codes for configuring the memory frequency and memory timing of the memory module; the central processing unit socket is used to plug the CPU, and the CPU is at least used to execute the memory configuration programming codes, so, after execution, they could provide a plurality of parameter options for memory frequency and memory timing of the memory modules to be selected one from them.

Abstract: An asynchronously pipelined SDRAM has separate pipeline stages that are controlled by asynchronous signals. Rather than using a clock signal to synchronize data at each stage, an asynchronous signal is used to latch data at every stage. The asynchronous control signals are generated within the chip and are optimized to the different latency stages. Longer latency stages require larger delays elements, while shorter latency states require shorter delay elements. The data is synchronized to the clock at the end of the read data path before being read out of the chip. Because the data has been latched at each pipeline stage, it suffers from less skew than would be seen in a conventional wave pipeline architecture. Furthermore, since the stages are independent of the system clock, the read data path can be run at any CAS latency as long as the re-synchronizing output is built to support it.

Abstract: A frequency regulator for varying a clock frequency of a power-supplied consumer operated in a clocked manner, wherein the frequency regulator is implemented to perform an overall variation of the clock frequency from an actual frequency to a set frequency, such that the overall variation is obtained by a plurality of clock changes, each with a different amount of change, wherein each of the respective amounts of change depends on a power change caused by the associated clock frequency change.

Abstract: The present invention provides a method and mechanism for data recovery with phase synchronized clock using interpolator and timing loop module and a data latching circuit. The interpolator can be considered as a programmable delay circuit with a specified delay resolution over the clock period.

Abstract: A method and system for shaping an electronic pulse with a two-pulse response. An input node receives an initial electronic pulse and splits the electronic pulse into a first path and a second path. An output node combines together the first path and the second path into an output path, and transmits a shaped electronic pulse, matched to an output impedance. An Ethernet chip generates two pulses and transmits the pulses along a first path and a second path respectively. A power combiner/splitter combines together the pulses along the first path and the second path into an output path, and transmits a shaped electronic pulse, matched to an output impedance.

Abstract: A computer system for writing data to a memory is disclosed. The memory controller in the computer system comprises a system clock, which is generated by the memory controller. A first register captures the lower data word based on the rising edge of the system clock. A second register, coupled to the first register, captures the output of the first register based on the rising edge of the system clock. A third register, captures the upper data word based on the falling edge of the system clock. A forth register, coupled to the third register, captures the output of the third register based on the falling edge of the system clock. A first multiplexer is coupled to a forth register and a second register. A delay element, coupled to the system clock and a first multiplexer, adjusts the phase of the system clock. A second multiplexer, coupled to the system clock, generates a data strobe.

Abstract: A controller may include a measurement circuit configured to generate a proxy signal representing delay variations in the controller. The measurement circuit may also generate a measurement value from the proxy signal. A control circuit may be configured to convert the measurement value into a control value. A delay circuit may be adjusted by the control value to alter an amount of delay of a signal.

Abstract: A programmable delay clock buffer circuit, preferably implemented in a single IC, includes a clock circuit and a plurality of variable delay lines. The clock circuit receives an input clock and is clock feedback signal and generates an intermediate clock. Each of the delay lines is configured to receive the intermediate clock and to receive at least one delay control input. A first variable delay line of the plurality is configured to generate, based on a first delay control input, a first delay from the intermediate clock to produce a clock output signal. A second variable delay line of the plurality is configured to generate, based on a second delay control input, a second delay from the intermediate clock to produce a clock feedback signal. A method of distributing clock with through programmable delay lines is also presented.

Abstract: The invention provides an integrated circuit with reduced electromagnetic interference induced by memory access. The integrated circuit includes a random code generator, a request receiver and a memory unit. The random code generator generates a plurality of random codes according to a predetermined delay parameter. The request receiver obtains an input clock signal according to a plurality of data requests and spreads the spectrum of the input clock signal based on the random codes to derive a non-periodic output clock signal. The memory unit accesses image data to be displayed in response to the data requests and the output clock signal.

Abstract: A memory controller performs a read test for each of a plurality of memory devices to generate a read delay time of each memory device. There is a prime memory device and a subset of memory devices. For each memory device of the subset, the read delay time for the prime memory device is compared with the read delay time of each memory device of the subset of memory devices to generate a differential delay for each memory device of the subset. For each subset memory device, a write test start time of the prime memory device is combined with a differential delay of each memory device to generate a write test start time for the each memory device. A write test for each memory device uses the write test start time for each subset memory device to generate a write launch time for each subset memory device.

Abstract: An interval centroid-based watermark encoder encodes a watermark into a packet flow. Intervals are defined for the packet flow. Some of the intervals are selected as group A intervals while other intervals are selected as group B intervals. Group A and group B intervals are paired and assigned to watermark bits. A first or second value may be encoded by increasing the relative packet time between packets in either the group A (for the first bit value) or group B (for the second bit value) interval(s) of the interval pair(s) assigned to the watermark bits that are to represent the first or second bit value and the beginning of the same group interval(s). The relative packet times may be measured by a decoder and used to calculate a centroid difference for each interval pair. The centroid differences may be used to reconstruct the watermark.

Abstract: The invention relates to an embedded system, and in particular, to an embedded system capable of compensating setup time violation. An embedded system comprises a serial flash and an access circuit. The serial flash further comprises an input pin and an output pin. The access circuit further comprises a processor, a shift register, a serial flash controller, and a time compensator. The input pin receives an adjusted input signal and the output pin sends an output signal. The processor controls the operation of the access circuit. The serial flash controller enables an operational clock of the access circuit. The time compensator compensates a timing of the output signal by referring to the operational clock. The shift register converts data in parallel form to serial form.

Abstract: A circuit is described comprising a first (10) and a second circuit module (20) and a synchronization module (30). The first and the second module are mutually asynchronous, and are coupled by the synchronization module. The synchronization module (30) comprises: a transfer register (31) for storing data which is communicated between the two circuit modules, a control circuit (32) for controlling the register in response to a respective timing signal (St1, St2) from the first and the second circuit module, the control circuit comprising a control chain for generating a control signal (CR) for the transfer register (31). The control chain includes at least: a repeater (34) for inducing changes in the value of the control signal, at least one edge sensitive element (35) for delaying a change in the signal value until a transition in a selected one of the timing signals is detected.

Abstract: Serializing circuitry is provided that can multiplex multiple device output signals and that can drive time-multiplexed data signals on the bus wires of a data path of an electronic system. Bus registers placed at the ends of the bus wires can register or buffer the data signals transmitted over the bus wires. The registered signals may be passed on to deserializing circuitry for demultiplexing the data signals to provide parallel device input signals. The bus registers and the serializing/deserializing circuitry can be provided along signal paths that require additional latency.

Abstract: A fault tolerant computer comprises a first unit, a second unit, a delay buffer and a delay time setting unit. The first unit executes a computer program in response to an input signal. The second unit executes the computer program in the same execution environment as the first unit in response to the input signal. The delay buffer controls a delay time of a timing when the input signal is input to the first unit with respect to a timing when the input signal is input to the second unit. The delay time setting unit sets the delay time to zero when receiving a synchronization mode signal and sets the delay time to be larger than zero when receiving a delay mode signal.

Abstract: A memory card includes a clock I/O circuit, a data I/O circuit, a delay element, and an adjustment value holding circuit. The clock input/output circuit receives a first clock from a host apparatus. The data I/O circuit receives a second clock from the host apparatus in a write timing adjustment mode. The data I/O circuit transmits and receives data to and from the host apparatus in a data transfer mode. In the write timing adjustment mode, the delay element adjusts a phase of the second clock in accordance with the first clock so as to receive the data received in the data transfer mode in response to the first clock. The adjustment value holding circuit holds an adjustment value for the phase of the second clock adjusted. In the data transfer mode, the delay element adjusts a phase of the data in accordance with the adjustment value.

Abstract: In emulation systems having a plurality of chips, data communicated between the chips needs to be synchronized. A receiver chip may push or pull on incoming data from an emitter chip in order to synchronize it with a receiver clock. Unexpected latency on the link between the emitter and receiver chips may also be adjusted for.

Abstract: A memory system and method according to various aspects of the present invention comprises a memory and an adaptive timing system for controlling access to the memory. The adaptive timing system captures data in a data valid window (DVW) in a data signal. In one embodiment, the adaptive timing system comprises a delay circuit for sampling the data signal at a midpoint of the DVW. The adaptive timing system may also comprise an identifying circuit for identifying whether the midpoint of the DVW corresponds to an actual midpoint of the DVW and adjusting the delay circuit accordingly.

Abstract: The present invention relates to an event driven digital signal processor 1 comprising: a central arithmetical unit 5, a register 4, a controller 3, an instruction memory 2, and input/output devices. The instruction memory 2 is arranged to include time performance constraints and events. An event control unit 6 is arranged to recognize an event and to control processing to be carried out as a consequence of the event while fulfilling the time performance constraints. The controller 3 is arranged to suspend processing of the time performance constraints after initiating operations in the event control unit 6. The controller 3 resumes processing when advised by the event control unit 6.

Abstract: The delay locked loop (“DLL”) delay interval can be locked to stop the DLL from wasting power in unnecessarily switching to synchronize the device with the DLL is associated to the system clock. This is achieved by adding logic sensing when a DRAM device will not imminently be called upon to output data and when the device has stabilized. Waiting for the DLL delay interval to stabilize before locking the delay interval still allows the DLL to immediately and effectively resume operations when the DLL is needed to synchronize the output of the DRAM device with the system clock. The DLL delay interval can be locked, together with the DLL clock, after the DRAM device is deselected by the chip select control line, after a number of no operation commands have been received, and/or after any command issued to the DRAM device has been completed.

Abstract: A high-speed double or quadrature data rate interface semiconductor device and a method thereof are provided. A transmitter (e.g., a data transmitting semiconductor device) for high-speed data transmission transmits a first strobe signal and a second strobe signal, which have a phase difference of 90 degrees there-between, a first group (byte of) data, and a second group (byte of) data. The transmitter adjusts the phase of at least one of the first and second strobe signals based on phase-error information fed back from a receiver and then transmits the phase-adjusted strobe signal to the receiver. The receiver receives the first and second strobe signals from the transmitter and receives the first group (byte of) data and the second group (byte of) data using the first and second strobe signals. The receiver does not require a phase-locked loop (PLL) or a delay-locked loop (DLL), thereby decreasing the circuit area and power consumption of the receiver.

Abstract: Embodiments of the invention are generally directed to systems, methods, and apparatuses for the active training of memory command timing. In some embodiments, the CMD/CTL timing is actively trained using active feedback between memory modules and the memory controller. Other embodiments are described and claimed.

Abstract: A circuit for transitioning clocking speeds, or frequencies, is provided. With this circuit, a clocking circuit providing a first clock signal at a first clock frequency is coupled to a counter. A comparator and a first divider are coupled to an output of the counter. The first divider outputs a second clock signal at a second clock frequency. A second divider is interposed between the clocking circuit and the counter. A processor is coupled to an output of the first divider.

Abstract: A data processing apparatus includes a first component for generating a signal operating in the first clock domain having a first clock period, and a second component for receiving the signal operating in the second clock domain having a second clock period. The second clock period is synchronous with but slower than the first clock period. Interface circuitry is provided for translating the signal between the first clock domain and the second clock domain, the interface circuitry operating in the first clock domain and comprising a storage element for temporarily buffering the signal generated by the first component before outputting that signal to the second component. Enable circuitry is used to control output of the signal from the storage element having regard to a specified input delay value identifying an input delay time of the second component expressed in terms of the first clock period.

Abstract: A clock distribution circuit, which is provided in IC that has a first sequential circuit receiving first clock through a first branch node on a first clock network, a second sequential circuit receiving second clock through a second branch node on a second clock network, and a data transfer path between the first and second sequential circuits, includes: a first PLL receiving a first feedback clock that is the first clock branched at the first branch node and outputting the first clock to the first clock network based on the first feedback clock; and a second PLL receiving a second feedback clock that is the second clock branched at the second branch node and outputting the second clock to the second clock network based on the second feedback clock. A branch node is provided at least one of between the first PLL and the first branch node and between the second PLL and the second branch node.

Abstract: A split delay-line oscillator for secure data transmission is disclosed. In one embodiment, an apparatus for a split delay-line oscillator for secure data transmission includes a first modulator/demodulator block in a first device, the first modulator/demodulator block operable to insert a first variable delay to modulate a frequency of a shared carrier signal passing through the first modulator/demodulator block, and a second modulator/demodulator block in a second device, the second modulator/demodulator block operable to insert a second variable delay to modulate the frequency of the shared carrier signal passing through the second modulator/demodulator block, wherein the first and second devices create a shared secret by contributing data on the frequency-modulated shared carrier signal.

Abstract: A debug network on a multiprocessor array having multiple clock domains includes a backbone communication channel which communicates with information nodes on the channel. The information nodes store and access information about an attached processor. The nodes are also coupled to registers within the attached processor, which operate at the speed of the processor. A master controller solicits information from the information nodes by sending messages along the backbone. If a message requires interaction with a processor register, the node performs the action by synchronizing to the local processor clock.

Abstract: A discussion of improving integrated device deterministic response to test vectors. For example, limiting the transmission delay for an integrated device's response within known bounds by synchronizing an initialization training sequence to a reset deassertion. Specifically, the proposal facilitates response determinism from the DUT by synchronizing training sequences and subsequently synchronizing flit transmission to reset assertion as sampled by reference clock.

Abstract: In a data processing apparatus and method using a first-in first-out (FIFO), the data processing apparatus includes a first sampling circuit, a delay circuit, and a FIFO device. The first sampling circuit samples a logic state of input data in response to a first edge of a first clock signal and holds a result of the sampling. The delay circuit receives and delays the first clock signal by a predetermined delay time and outputs a second clock signal. The FIFO device processes the result of the sampling output from the first sampling circuit using a FIFO method in response to a first edge of the second clock signal output from the delay circuit.

Abstract: A method for synchronizing a transmission of information over a bus, and a device having synchronization capabilities.

Abstract: A methodology and network tool for evaluating one-way directional delays in a packet network is described. The invention provides for a discrimination of the directional components of the delay experienced by packets travelling between nodes in a network. This identification of the directional delay component assists in an understanding of network behaviour and can be represented on a graphical user interface. Such methodologies are achieved without requiring clock synchronisation between clocks at each of the nodes.

Abstract: An asynchronously pipelined SDRAM has separate pipeline stages that are controlled by asynchronous signals. Rather than using a clock signal to synchronize data at each stage, an asynchronous signal is used to latch data at every stage. The asynchronous control signals are generated within the chip and are optimized to the different latency stages. Longer latency stages require larger delays elements, while shorter latency states require shorter delay elements. The data is synchronized to the clock at the end of the read data path before being read out of the chip. Because the data has been latched at each pipeline stage, it suffers from less skew than would be seen in a conventional wave pipeline architecture. Furthermore, since the stages are independent of the system clock, the read data path can be run at any CAS latency as long as the re-synchronizing output is built to support it.

Abstract: A double data rate elastic interface in which programmable latch stages provide an elastic delay, preferably on the driving side of the elastic interface. However, the invention is not limited to the driver side/chip, it can be implemented in the receiver side/chip as well. However, since the receiver side of an elastic interface already has complicated logic, the invention will be usually implemented on the driving side. The programmable latch stages on the driving chip side of the interface, can often operate at the local clock frequency (the same frequency as the elastic interface bus clock frequency), which in turn is half of the double data rate at which the receiving latch stages operate, thereby decreasing the logic and storage resources in the interface receivers. The programmable latch stages can also be used in the case that the local clock frequency is twice the elastic interface bus clock frequency.

Abstract: To provide inter-LSI data synchronized transfer with a transfer throughput satisfying a required performance without causing an operation timing difference of the entire system even when a wiring delay between LSIs varies on an evaluation board and an actual device. A master (LSI1) outputs transfer data and a transfer synchronization clock signal to a slave (LSI2). For the edge of a clock signal used for data output at the master (LSI1), the slave (LSI2) latches input data by using a reverse edge. Moreover, upon data transfer from the slave (LSI2) to the master (LSI1), the master (LSI1) selects a latch timing of input data from a plurality of timings so that the transfer time to an internal circuit of the master (LSI1) side is identical regardless of which latch timing is selected.

Abstract: An apparatus for synchronizing an output clock signal with an input clock signal includes a first timing synchronization circuit, control logic, and a counter. The first timing synchronization circuit is operable to generate a delay to synchronize a reference clock signal representative of the input clock signal with a feedback clock signal representative of the output clock signal responsive a strobe signal. The control logic is operable to generate an enable signal based on the reference clock signal and generate the strobe signal based on the feedback clock signal. The counter is operable to count cycles of the reference clock signal occurring between the enable signal and the strobe signal to generate a loop count for the first timing synchronization circuit.

Abstract: Provided is a test apparatus that tests a device under test, comprising a pattern generating section that generates a test pattern for testing the device under test; a signal supplying section that supplies the device under test with a test signal corresponding to the test pattern; a trigger generating section that supplies a trigger signal to an external instrument connected to the device under test; and a synchronization control section that outputs, to the trigger generating section, a synchronization signal instructing generation of the trigger signal, based on at least a portion of the test pattern generated by the pattern generating section.

Abstract: Clock skew may be detected measured and compensated for using phase detectors and variable delay adjusters. Phase detectors may be distributed throughout a clock distribution network and may be configured to analyze two clock signals to determine how often one signal leads the other. The output of the phase detectors may be measured and counted over a large number of clock cycles. The difference between the number of times one signal leads or lags behind the other may be used to determine the amount of delay to apply to the leading clock signal in order to minimize (reduce) skew between the two clock signals. The same techniques for detecting and measuring clock skew may also be used to detect and measure jitter in the clock signals. By configuring variable delay adjusters on clock signals, the amount of jitter in the clock signals can be measured or characterized.

Abstract: A method for operating cooperating, differing devices, particularly of a plant, with different controls controlling the control sequences and in particular with different control cycles, is characterized in that the clocks (IPOi) of the different controls (3.1, 3.2, 3.3) are interpolated on a common system clock (tTick) and that the control sequences are synchronized. An apparatus suitable for performing the inventive method correspondingly has at least one common interpolating device (5.3) for the controls (3.1, 3.2, 3.3) for interpolating the cycles (IPOi) of the different controls (3.1, 3.2, 3.3) on a common system clock (tTick) and at least one synchronizing device (5) for synchronizing the control sequences.

Abstract: Techniques are described for synchronizing multiple time-based data streams with independent clocks wherein relationships between clock rates of timing devices associated with the time-based data streams are determined, and based on these relationships, times in at least one of the time-based data streams may be translated to times in any of the other time-based data streams despite the data streams having independent clocks.

Abstract: A system and method for using variable delay adjusters located at various points across an integrated circuit to measure clock skew and jitter for clock signals of the integrated circuit. A delay controller of the integrated circuit may measure and compensate for clock skew detected between two clock signals by configuring variable delay adjusters located inline with the respective clock signals. Such a delay controller may also use the variable delay adjusters to correct duty cycle errors in a clock signal and may further utilize the variable delay adjusters to measure and characterize jitter detected on the clock signals.