Counter with correction circuitry

The invention concerns counting circuitry for providing a corrected count value based on the number of rising and falling edges of an input signal occurring during a reference time period, the counting circuitry comprising a counter arranged to provide a first count value based on one of the number of said rising edges of said input signal occurring during said reference time period, and the number of said falling edges of said input signal occurring during said reference time period; characterized in that said counting circuitry further comprises adjustment circuitry (-) arranged to generate a corrected count value by determining the state of said input signal at the start time and end time of said reference time period, and adjusting said first count value if the state of said input signal at the start of said reference time period is different from the state of said input signal at the end of said reference time period.