Patent ID: 8687682

Claim:
In a port for receiving serialized data from a transmitter having a filter with at least one adjustable coefficient, the at least one adjustable coefficient having a value, the port comprising: a receiver adapted to receive the filtered serialized data from the transmitter and generate decision bits and error values, the error values generated in response to the received filtered serialized data, the decision bits being a delayed version of a known data pattern and time-aligned with the error values; a controller coupled to the receiver; and a back-channel transmitter coupled to the controller; wherein the controller is adapted to: a) receive the error values from the receiver; b) adjust the value of the at least one coefficient by an amount based on an adaptation gain value, the decision bits, and the error values; c) transmit the value of the at least one adjusted coefficient to the filter via the back-channel transmitter; d) repeat steps a) through c) for a first time period using a first adaptation gain value until changes in the at least one coefficient adjusted in step b) is less than a first threshold amount; and then e) repeat steps a) through c) for a second time period using a second adaptation gain value that is less than the first adaptation gain value until changes in the value of the at least one coefficient adjusted in step b) is less than a second threshold amount, the second threshold amount being less than the first threshold amount.