Nordic Semiconductor ASA
Clock calibration

Abstract:

A circuit system comprises a processor, a first clock with a first frequency, a second clock with a second frequency, such second frequency being higher than said first frequency and a clock calibration module. The clock calibration module comprises a plurality of counters configured to count cycles of the second clock when triggered. Each of the plurality of counters is configured to be triggered at successive cycles of the first clock. Each of the plurality of counters is configured, after a predetermined number of cycles of the first clock, to output a count of elapsed second clock cycles and the processor is configured to determine, using the counts outputted by the plurality of counters, a ratio between the first frequency and the second frequency.