摘要:
A method is provided for sampling a data strobe signal of a memory cycle and determining a receiver enable phase based upon the data strobe signal. The method also includes performing a memory write cycle and a subsequent read cycle and training a read data strobe cycle at a one-quarter memory clock periodic offset. The method also includes determining a correct receiver enable delay in response to a successful read data strobe training cycle. Computer readable storage media are also provided. An apparatus is provided that includes a communication interface portion that is coupled to a memory portion and to a processing device. The apparatus also includes a first circuit portion, coupled to the communication interface portion. The first circuit portion monitors memory cycles on the communication interface portion, determines a receiver enable cycle phase and train a receiver enable cycle without using receiver enable seed.
摘要:
A method is provided for sampling a data strobe signal of a memory cycle and determining a receiver enable phase based upon the data strobe signal. The method also includes performing a memory write cycle and a subsequent read cycle and training a read data strobe cycle at a one-quarter memory clock periodic offset. The method also includes determining a correct receiver enable delay in response to a successful read data strobe training cycle. Computer readable storage media are also provided. An apparatus is provided that includes a communication interface portion that is coupled to a memory portion and to a processing device. The apparatus also includes a first circuit portion, coupled to the communication interface portion. The first circuit portion monitors memory cycles on the communication interface portion, determines a receiver enable cycle phase and train a receiver enable cycle without using receiver enable seed.
摘要:
A system and method of data communications between a first device and a second device is disclosed. The method includes generating a first clock signal at the first device and generating a second clock signal having a phase offset from the first clock signal. The clock signals are transmitted from the first device to the second device. The method further includes regulating transmission of a read strobe signal sent from the second device to the first device utilizing the first clock signal. The method also includes regulating transmission of a data transfer signal sent from the second device to the first device utilizing the second clock signal.
摘要:
Various method and apparatus embodiments for training a delay for enabling a data strobe signal in a memory subsystem are disclosed. In one embodiment, a system includes a memory controller configured to receive a data strobe signal. The memory controller includes a training circuit. The training circuit includes a first storage circuit coupled to receive the data strobe signal on a data input and an enable signal on a clock input, and a training unit configured to, based on an output signal received from the first flip-flop, adjust a phase of the enable signal until an assertion of the enable signal coincides with a preamble indication in the data strobe signal.
摘要:
An apparatus interfaces a first circuit using a first supply voltage and a second circuit using a second supply voltage different from the first supply voltage. The apparatus includes a driver circuit having a driver network comprising driver supply voltage terminals connected to controllable switches. The controllable switches include resistive elements or are separated from resistive elements. A receiver circuit has a receiving network comprising a resistive element and receiver supply voltage terminals and a connection line connecting the driver circuit and the receiving circuit. The controllable switches have two switch configurations, a first switch configuration resulting in a high voltage on the connection line and a second switch configuration resulting in a low voltage on the connection line.
摘要:
The present invention relates to a method and apparatus for generating an output signal in dependence on a phase difference between two periodic signals. The present invention is particularly useful in phase locked loops and delay locked loops, in which a controllable oscillator or a controllable delay device is controlled on the basis of the phase difference determined by means of phase detection, in such a way that a control signal can be obtained, the phase lag or frequency of which has a firm relationship to the reference signal.
摘要:
A decision feedback equalization (DFE) receiver and method are provided. The DFE receiver is configured to sample data bits from a data bus. The DFE receiver includes a data sampler configured to sample a current data bit from the data bus using one of a first, second and third voltage reference. The DFE receiver also includes multiplexing logic configured to select one of the first, second and third voltage references based on a prior data bus level. The wherein the first voltage reference is selected if the prior data bus level was a logic zero. The second voltage reference is selected if the prior data bus level was a logic one. The third voltage reference is selected if the prior data bus level was tri-state.
摘要:
An arrangement for generating a transmission clock signal and a reception clock signal is proposed in which only a single voltage-controlled oscillator is used, the reception clock signal being generated by phase-adjusting means whereas the transmission clock signal is generated directly by the voltage-controlled oscillator. Cross-talk between a plurality of voltage-controlled oscillators can be prevented in this way. Also, various measures are proposed for optimizing a circuit of this kind.
摘要:
A clock signal extraction device for extracting a clock signal from a periodic data signal includes a phase detector for detecting a first phase difference between rising edges of said data signal and a rising edges clock signal and for detecting a second phase difference between falling edges of said data signal and a falling edges clock signal. The device also includes a clock generator for generating said rising edges clock signal so that said first phase difference is minimized, for generating said falling edges clock signal so that said second phase difference is minimized, and for generating said clock signal in dependence on said first phase difference and said second phase difference. A method for extracting a clock signal from a periodic data signal is related to the device.
摘要:
An apparatus for providing a signal for transmission via a signal line includes a controller circuit having an output for a signal indicating whether the signal line is or will be in an inactive state and a switching circuit coupled to the controller circuit and having an output coupled to the signal line. The output is switched between different signal levels, if the signal indicates that the signal line is in an inactive state.