Interface with variable data rate

A method for operating a wired link receiver in a calibration mode of operation, comprising:

• at a device having the wired link receiver:
• receiving from a wired link a baseband signal that includes data transmitted at an initial data rate by a transmitter of another device;
• after receiving the baseband signal with data transmitted at the initial data rate, continuing to receive the baseband signal with data transmitted at an increased data rate that is a non-integer multiple of the initial data rate;
• and
• iteratively:
• determining a performance metric of the wired link, wherein the performance metric comprises at least one of a timing margin corresponding to an error rate of the wired link and a voltage margin corresponding to the error rate of the wired link, and
• in accordance with the determined performance metric of the wired link, changing a voltage swing of the baseband signal transmitted over the wired link,
• the performance metric of the wired link at a final iteration corresponding to an error rate of the wired link that is no greater than a set error rate.

A device, comprising:

• a node to couple to a wired link;
• a first transmitter having an output coupled to the node;
• a receiver having an input coupled to the node for receiving a first baseband signal that includes data transmitted by another device having a second transmitter, the second transmitter having an output coupled to the node;
• and
• control logic to determine a first performance metric, the first performance metric comprising at least one of a timing margin corresponding to an error rate of the wired link and a voltage margin corresponding to the error rate of the wired link;
• wherein, during a first calibration process, an initial data rate of communicating information over the wired link using the first baseband signal is increased from the initial data rate to a first increased data rate that is a non-integer multiple of the initial data rate, and in response to the determination of the first performance metric, a voltage swing of the second transmitter output coupled to the node is adjusted, and
• wherein the output of the first transmitter is for transmitting a second baseband signal via the wired link, the control logic is coupled to the first transmitter to adjust a voltage swing of the first transmitter in accordance with a second performance metric determined by control logic of the other device.