10GBase-T training algorithm

Abstract

A method of identifying and correcting each of the changes that may occur with wire pairs between the transmitter and receiver in Ethernet 10GBase-T cabling is provided. The method includes four wire pairs A, B, C and D, a polarity swapping and scrambler state machine that determine if the chosen pair matches the requirements for pair A. A slave Tap state machine generates a rule for correct B, C and D patterns based on a pair chosen as pair A. The cables B, C and D are iteratively swapped to rearrange the pair mapping into the polarity swap state machine, and a deskew state machine identifies the latency difference between the different pairs. If the rules are not satisfied, a new pair A is designated at the swapping state machine and the process is repeated until the rules are satisfied.

1 . A method of recognizing and correcting wire pair swapping between a transmitter and receiver in 10GBase-T Ethernet cabling comprising:
 a. providing four pairs of wires, wherein said wires transmit data between said transmitter and said receiver, whereby said wire pairs comprise A, B, C, and D, whereas said pairs are arranged in a quadrille pattern comprising two top pairs and two bottom pairs;   b. providing a cable swapping state machine, wherein said swapping state machine selects one pair from said top pairs, whereas said selected pair is designated as pair A;   c. providing a polarity swapping and scrambler lock state machine, whereby said lock state machine determines if said designated pair A is a correct choice for position A, whereas said lock state machine determines if said selected pair is inverted, wherein if said selection for A is not correct a next pair of said wires is designated and said determination is repeated until said requirements for pair A are met and said pair is not inverted;   d. providing a slave tap state machine, wherein said tap state machine establishes a rule for a correct B, C, and D pattern based on said determined pair A;   e. using said lock state machine to designate a second said top pair as pair B;   f. using said lock state machine to designate a first said bottom pair as pair C;   g. using said lock state machine to designate a first said bottom pair as pair D;   h. providing a deskew state machine, wherein said deskew state machine compares all said designations over all possible latencies with said rules generated by said slave tap machine, whereby if said rules are not satisfied said cable swap state machine reverses said designated pair C with designated pair D;   i. using said deskew state machine to re-compare all said designations over all possible latencies with said rules generated by said slave tap machine, wherein if said rules are not satisfied a new pair A is selected and steps b through i are repeated until said rules are satisfied.