Method for adjusting the mean frequency of a time base incorporated in an electronic watch

A method for determining a constant parameter of an inhibition value, or constant inhibition parameter, for adjusting a mean operating frequency of an electronic watch including an electronic device comprising:

• an internal time base comprising a time-measurement oscillator and a clock circuit, the time-measurement oscillator having a natural frequency and being arranged to provide a periodic time-measurement signal with said natural frequency, the clock circuit being arranged to receive the periodic time-measurement signal and to generate a clock signal with the mean operating frequency,
• an adjustment circuit for adjusting the mean operating frequency, including a memory storing at least said constant inhibition parameter, the adjustment circuit being arranged to inhibit, by predefined inhibition period and as a function of at least the constant inhibition parameter, one or more periods in the generation of a periodic signal internal to the clock circuit involved in the generation of the clock signal, such that the mean operating frequency is more precise, the internal periodic signal being derived from the periodic time-measurement signal,
• the method for determining the constant inhibition parameter includes the following steps, consisting in:
• ET1:
• from a first external pulse and a second external pulse received from a system external to the watch and separated by a measurement time corresponding to a reference number multiplied by a reference period for a periodic calibration signal derived from the periodic time-measurement signal and having a calibration frequency derived from the natural frequency, determining a calibration parameter representative of a ratio between a calibration period, equal to the inverse of the calibration frequency, and the reference period, and
• ET2:
• determining the constant inhibition parameter as a function of the calibration parameter.