Patent ID: 7729465

Claim:
A system comprising: a slave device; and a master device coupled to the slave device and configured to control data transfer between the master device and the slave device; wherein the master device is configured to adaptively modify transmit characteristics based upon information received from the slave device, subsequent to adaptively modifying a phase alignment of a receiver sample clock of the master device based upon cyclic redundancy code (CRC) information received from the slave device via one or more unidirectional CRC data paths, wherein the CRC information corresponds to data transmitted between the master device and the slave device via a plurality of bidirectional data paths; wherein the CRC information received from the slave device includes data eye information sent via the one or more unidirectional CRC data paths, wherein the data eye information corresponds to an edge position of data signal transitions received by the slave device on the plurality of bidirectional data paths; and wherein the CRC information and the data eye information are multiplexed on the one or more unidirectional CRC data paths, and wherein the CRC information sent from the slave device during different bit times dependent upon whether the master device is writing or reading the data transmitted between the master device and the slave device via a plurality of bidirectional data paths.