This module is ideally suited to amplifying and organising biometric pulse rates for use with microcontrollers. A 3.5mm jack can be used to provide input for pulse measurement. The HL8038 chipset then amplifies and organizes the rates and provides a analog response for use within your project.

The module is best used by monitoring the falling edge of a signal as it is received and calculating the time since the last falling edge. This is an ideal situation for the use of interrupts. Simply monitor the input pin for falling edges of a signal. On finding one trigger an interrupt and calculate the time since the last interrupt. Now divide 60000 (50000 if set by jumper) by the time between interrupts to produce a pulse value.