Frequency measurement of heart beat rate - uses count of clock pulses during set number of beats and calculation of reciprocal

摘要

The circuit determines the frequency e.g. of heart-beats, measured in beats per minute. During a certain number of events (e.g. ten heart-beats or more), clock pulses appearing during this period are counted. Their repetition frequency is preselected and known. The measurement interval is calculated from the number of clock pulses and their frequency, and divided by the number of events. The reciprocal of this result is obtained and displayed.