Disclosed is a method of determining time in a digital processing system, comprising, in a present cycle of a first digital clock: accessing a reference time counter for a reference digital clock, wherein the reference time counter increments in value by a fixed amount at every cycle of the reference digital clock, the reference digital clock being of a higher accuracy than the first digital clock; accessing a first time counter for the first digital clock, wherein the first time counter increments in value by an updatable increment amount at each cycle of the first digital clock; and comparing at least one part of the reference time counter with at least one corresponding part of the first time counter. Based on the comparing, an adjustment is made to one or more attributes of the first time counter, so that first time counter at least approximates the reference time counter.