A method and apparatus to support communication between components in
different clock domains having a rational clock frequency ratio of N/D.
In one embodiment, a combination of integer phase generators are employed
to produce phase control signals during an overall cycle having N phases,
wherein the overall cycle is a combination of primary cycles having D
phases and an adjustment cycle having R phases, wherein R is the
remainder of N/D. For clock frequency ratios of less than 2:1, a
combination of 2:1 and 1:1 phase generators are employed. Clocking
signals are generated by phase generator logic to provide timing control
between communicating components in the different clock domains. In one
embodiment, the phase generator logic is implemented in a programmable
phase generator.