Patent ID: 6571346
Filing Date: 2003-05-27
Classification: G06F

Abstract:
A method for communicating between a master and slave device, comprising the steps of:a) sending a sequence of data sets and a clock signal (â€œBus clockâ€ ) from the master to the slave, wherein each successive set is are asserted by the master for a certain amount of time; b) receiving the data and Bus clock by the slave, including capturing the data by the slave, responsive to the received Bus clock; c) generating a slave I/O clock by the slave device from the received Bus clock, wherein in step b), capturing the data by the slave responsive to the received Bus clock comprises timing the capturing responsive to the slave's I/O clock; d) generating by the slave, from the received Bus clock, a clock (â€œslave Local clockâ€ ) for clocking operations on the slave, wherein the slave Local clock is generated open-loop from the received Bus clock, so that the slave's local clock is not phase locked to the received Bus clock; e) holding the sequence of the received data sets in a sequence of latches in the slave, wherein the time for which each step is held in step e) is longer than the time for which each set is asserted in step a); and f) reading the data sets in their respective sequence from the latches, responsive to the Local clock, so that the holding of respective data sets for the relatively longer time in multiple latches and the reading of the data in sequence increases allowable skew of the Local clock relative to the received Bus clock, wherein second data sets are launched back to the master device by the slave device, responsive to the slave Local clock and the data sets received by the slave, and wherein the second data sets are received and captured by the master device, and are read by the master device responsive to a master Local clock.