Example Description

this example is use to measure heart rate of human

Requirement Components:
    extend board

work with arduino extended board, which has heart rate sensor

during the measurement, user has to lie his pulp on the sensor and do not rock the sensor

the test code will return back the heart rate

Connect 
  - I2C0 SDA (PA_19) to extended board's SDA 
  - I2C0 SCL (PA_22) to extended board's SCL 
  
Build code
1. Please be sure to copy inc\heart_interface.h, inc\HRM_2197.h 
2. Include hr_library.a in IAR project. Add hr_library.a into folder "lib" in IAR project.