Agere Systems Inc.

Lsi Corporation

Yasser Ahmed

Lane Allen Smith

Xingdong Dai

Mohammad Shafiul Mobin

Vladimir Sindalovsky

Gregory W Sheets

Christopher John Abel

Shawn Michael Logan

Robert D Brink

Robert J Kapuschinsky

Samuel Khoo

Ashok Khandelwal

In order to compensate for phase offset between different sets of circuitry having different synchronous clock domains, transmit (TX) circuitry of one domain is configured to transmit a pattern signal (e.g., a pseudo random bit sequence) to receive (RX) circuitry of the other domain. The RX circuitry cycles through a number of different phase-shifted RX clock signals to determine which selected clock signals result in valid RX pattern signals. The RX circuitry is then able to select one of the phase-shifted clock signals for use in normal processing of an RX data signal received from the TX circuitry.

Phase alignment between phase-skewed clock domains

Methods and apparatus are provided for detecting and decoding adaptive equalization training frames (having a frame marker comprised of a string of binary ones and binary zeroes). Training frames are detected by shifting the received data; inserting at least one binary value at one end of the shifted received data to generate a modified version of the received data; applying a logic function to the received data and the modified version of the received data that identifies when corresponding bit positions have different values; and detecting the frame marker when an output of the logic function has a first binary value in an approximate middle of a string of a second binary value. The training frames are decoded using a distance between the approximate center of the frame marker and a predefined binary value in an output of the logic function.

Methods and apparatus for detecting and decoding adaptive equalization training frames

Methods and apparatus are provided for detecting and decoding adaptive equalization training frames (having a frame marker comprised of a string of binary ones and binary zeroes). Training frames are detected by shifting the received data; inserting at least one binary value at one end of the shifted received data to generate a modified version of the received data; applying a logic function to the received data and the modified version of the received data that identifies when corresponding bit positions have different values; and detecting the frame marker when an output of the logic function has a first binary value in an approximate middle of a string of a second binary value. The training frames are decoded using a distance between the approximate center of the frame maker and a predefined binary value in an output of the logic function.

In an exemplary embodiment, a data alignment system comprises a First-In First-Out register (FIFO), a programmable pattern generator connected to the FIFO, and a controller connected to the programmable pattern generator and the FIFO. The FIFO is configured to provide data to or receive data from a first data lane of a serial data link having one or more lanes. Each data lane of the serial data link is configured to transmit a respective serial data stream. The programmable pattern generator is configured to generate a plurality of alignment symbols. The controller is configured to manage the alignment of the one or more data lanes of the serial data link and the insertion of a selected one of the plurality of alignment symbols into each of the serial data streams.

Data alignment method for arbitrary input with programmable content deskewing info

The present invention implements an apparatus for calibrating a phase locked loop (PLL) circuit. The apparatus includes a detector for detecting frequencies of a reference signal and a controlled oscillator contained in the PLL circuit. The detector outputs the frequency difference to a control circuit. The control circuit is programmed to adjust one or more control signals to the controlled oscillator based upon the frequency difference in an orderly fashion to complete the calibration process.

Programmable linear trimming method and system for phase locked loop circuit calibration

A low-latency, peer-to-peer TDM bus including one or more data lines and one or more control lines is provided. Attached devices access the bus sequentially in order of their bus addresses. During a device's access period, if the device has data to transmit, the device places its address on the data lines, asserts a START signal on the bus, and proceeds to transmit data to the other devices on the bus. When the data transmission is completed, the device asserts an END signal on the bus, thus passing control of the bus to the next device in the sequence. If the device has no data to transmit, the device simply places its address on the data lines, asserts the START signal, and asserts the END signal, and control passes directly to the next device in line. In this manner, each device has an opportunity to transmit on the bus.

Round-robin bus protocol

An integrated circuit device for use in a node of a communication system is provided. The integrated circuit device includes a memory configured to store data written thereto by a receiver associated with the node in accordance with a receiver clock, and to read data therefrom by a transmitter associated with the node in accordance with a transmitter clock. The integrated circuit device also includes a control logic circuit that is in communication with the memory, and is configured to send a control signal to the transmitter to adjust a speed of the transmitter clock responsive to an operating condition of the memory.

Methods and apparatus for asynchronous serial channel connections in communication systems

Disclosed is a system and method for testing a dual mode interface. The dual mode interface includes a first strobe circuit and a second strobe circuit configured to be inoperable during a first operational mode of the interface and operable during a second operational mode of the interface. The dual mode interface also includes a first data circuit and a second data circuit configured to be operable during the first operational mode and the second operational mode. The dual mode interface also includes a signal line connecting an output of the second strobe circuit with an input of the first strobe circuit and a switch element configured to activate said signal line in response to receipt of a test signal.

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Macungie, PA, United States of America

Yasser Ahmed