Patent ID: 7272527

Claim:
A method of testing a clock generation circuit in an electronic device having an interface circuit which operates using a clock of a comparatively fast clock source, comprising the steps of: connecting an electronic device to be measured to an electronic device which serves as reference using the interface circuit, synchronizing the electronic device to be measured with the reference electronic device, and counting clock pulses of the clock source in use of counters in the electronic device to be measured and in the reference electronic device; halting, after a prescribed time has elapsed, the counting by the counters of the electronic device to be measured and of the reference electronic device; transmitting the count value of the counter of the electronic device to be measured from the electronic device to be measured to the reference electronic device; and comparing the transmitted count value with the count value of the counter of the reference electronic device in the reference electronic device, and inspecting for deviations in the frequency of the clock source in the electronic device to be measured.