A method for deriving an estimation value of a clock-error for a slave clock, the clock-error being defined as the difference between an actual slave clock period, TLCLK, and a nominal slave clock period, TLCLK_n, wherein the slave clock is set at the nominal slave clock period (TLCLK_n) and outputs a sequence of slave clock pulses mutually separated by the actual slave clock period (TLCLK), the method comprising: - receiving a sequence of master clock pulses mutually separated by a master clock period, THCLK, that is output from a master clock, - providing a measurement time period that begins at a starting time point (43_s) and ends at an ending time point (43_e), wherein the measurement time period includes a common multiple time period, the common multiple time period ends at the ending time point (43_e) and has a length in time that is a first multiple (n) of the nominal slave clock period (TLCLK_n) and is a second multiple, m, of the master clock period (THCLK), - providing a sequence of storing time points (43_i) temporally displaced within the common multiple time period by the actual slave clock period (TLCLK), the last of the storing time points being the ending time point (43_e) of the measurement time period, - starting to count the slave clock pulses and the master clock pulses at the starting time point (43_s), - for more than one storing time point (43_i), storing a master count value that represents the counted master clock pulses at the time associated with the respective storing time point (43_i) to obtain a plurality of stored master count values for the corresponding measurement time period, - deriving an actual master count sum value by summing over all the stored master count values of the plurality of the stored master count values, - deriving, for the more than one storing time points, a nominal master count sum value based on the equation: sum of [ (R-1) x m + i x TLCLK_n/THCLK], whereby R is the number of common multiple time period(s) within the measurement time period, m is the master count value defining the common multiple time period, i is the number of counted nominal slave clock periods of an ideal slave clock within the last common multiple time period, the ideal slave clock being the slave clock without said clock error, and - deriving the estimation value of the clock-error for the slave clock by comparing the actual master count sum value to the nominal master count sum value. - receiving a sequence of master clock pulses mutually separated by a master clock period, THCLK, - providing a measurement time period that begins at a starting time point (43_s) and ends at an ending time point (43_e), wherein the measurement time period includes a common multiple time period, the common multiple time period ends at the ending time point (43_e) and has a length in time that is a first multiple (n) of the nominal slave clock period (TLCLK_n) and is a second multiple, m, of the master clock period (THCLK), - providing a sequence of storing time points (43_i) temporally displaced within the common multiple time period by the actual slave clock period (TLCLK), the last of the storing time points being the ending time point (43_e) of the measurement time period, - starting to count the slave clock pulses and the master clock pulses at the starting time point (43_s), - for more than one storing time point (43_i), storing a master count value that represents the counted master clock pulses at the time associated with the respective storing time point (43_i) to obtain a plurality of stored master count values for the corresponding measurement time period, - deriving an actual master count sum value by summing over all the stored master count values of the plurality of the stored master count values, - deriving, for the more than one storing time points, a nominal master count sum value based on the equation: sum of [ (R-1) x m + i x TLCLK_n/THCLK], whereby R is the number of common multiple time period(s) within the measurement time period, m is the master count value defining the common multiple time period, i is the number of counted nominal slave clock periods of an ideal slave clock within the last common multiple time period, the ideal slave clock being the slave clock without said clock error, and - deriving the estimation value of the clock-error for the slave clock by comparing the actual master count sum value to the nominal master count sum value.