Broadcom Corporation

Other

Standard Microsystems Corporation

Andrew J Castellano

Gary S Huff

John K Lenell

David L Fisher

Pieter Vorenkamp

Chun-Ying Chen

Pinghua Peter Yang

A method and apparatus for generating a performance indicator in a high-speed communication system. A plurality of disparate communication status signals with differing formats from a transceiver are combined in a logic module to create a single link quality indicator signal. The link quality indicator signal is used to encode different operational states of the transceiver from fully operational, to marginally operational, to failed. The link quality indicator signal is advantageously employed to drive a LED creating a visual performance indicator.

Channel quality indicator for a communication system

Inter-device adaptable interfacing clock skewing. The invention is operable in either one of both of a transmit mode and a receive mode to perform skewing of a transmitted and/or a received signal. The operational parameters including frequency and phase may be determined during auto detect/auto negotiation, they may be programmed externally, or they may be user selected in various embodiments. A device may include a clock generator, one or more divider, and one or more delay cells internally to the device. If desired, a high frequency clock is generated within the device and then divided down to generate the appropriate clock signal that supports the communication and interaction between multiple devices. Registers and/or pins may be used to select the clock frequency and phase of output clock signals. The present invention supports multiple Ethernet protocols between multiple devices including 10BaseT, 100BaseT, and 1000BaseT.

Inter-device adaptable interfacing clock skewing

A method of processing a data stream through a buffer is performed in accordance with a write clock and a read clock. The buffer has a plurality of sequentially numbered storage cells. The method includes the steps of selecting an initial preload value, with the selecting step including determining a product of the maximum frequency offset between the write and read clocks, and a maximum time between arbitrary symbols in the data stream. The storage cells then receive data units in response to a write pointer. Data units are then provided from the storage cells in response to a read pointer.

Adjustable elasticity FIFO buffer with preload value having a number of storage cells equal to frequency offset times between data units in a data stream

Performance indicator for a high-speed communication system

Each packet normally consists of a preamble, start-of-frame delimiter and data. The preamble has nibbles each having a particular format. A header substituted for preamble nibbles by an individual one of the originating devices in a plurality, and an individual one of the ports in such originating device, indicates such originating device and such port. Such port in such originating device sends such modified packet to others of the originating devices and to an observing station. The header format is such that the last nibble in the header and the remaining preamble portion will not be confused with any two (2) nibbles in the header. A particular one of the originating devices indicated in the data converts the header back to the preamble format and transmits the converted packet to a receiving station. The observing station records the individual originating device, and the individual port in such device, indicated in the header. Each packet includes at its end a trailer formed from a plurality of nibbles and indicating whether or not a collision has occurred between such packet and a packet from another one of the originating devices. The trailer in each packet may also indicate additional information&#x2014;e.g. whether the packet (a) is a normal packet originally formed, (b) is a runt packet, (c) is from an unacceptable source and (d) the delay between each packet end and the next packet start. The information in the trailer for each packet passes to the observing station.

System for and method of providing a header and a trailer in data packets

Adjustable elasticity FIFO buffer have a number of storage cells equal to a frequency offset times a number of data units in a data stream

The drift between a write pointer and a read pointer processing packets of data through a FIFO buffer is compensated for by adjusting the start of the read pointer relative to the write pointer. The FIFO buffer is sized to include a number of storage cells equal to the product of the maximum frequency offset between the write clock and read clock and the maximum number of data units in a packet. Initially the start of the read pointer is delayed, relative to the write pointer, by a portion of the number of storage cells in the FIFO. During the processing of a data packet it is determined whether the read pointer is drifting toward or away from the write pointer. If the read pointer is drifting away from the write pointer, for subsequent data packets, the read pointer is started almost immediately after the write pointer writes to the first storage cell in the FIFO. If the read pointer is drifting toward the write pointer, for subsequent data packets, the read pointer is started almost immediately prior to the time at which the write pointer writes to the last storage cell in the FIFO.

Self-adjusting elasticity data buffer with preload value

A header substituted for preamble nibbles by an individual one of the originating devices in a plurality, and an individual one of the ports in such originating device, indicates such originating device and such port. Such port in such originating device sends such modified packet to others of the originating devices and to an observing station. The header format is such that the last nibble in the header and the remaining preamble portion will not be confused with any two (2) nibbles in the header. A particular one of the originating devices indicated in the data converts the header back to the preamble format and transmits the converted packet to a receiving station. The observing station records the individual originating device, and the individual port in such device, indicated in the header. Each packet includes at its end a trailer formed from a plurality of nibbles and indicating whether or not a collision has occurred between such packet and a packet from another one of the originating devices.

Growing community of inventors

Laguna Beach, CA, United States of America

Andrew J Castellano