Description Working Principle Description: Light-dissolving method: measuring the pulse and blood oxygen saturation by using human tissue to cause different light transmittance when the blood vessel beats; Light source: a specific wavelength of light-emitting diode selective for oxyhemoglobin (HbO2) and hemoglobin (Hb) in arterial blood; Transmittance is converted into electrical signal: the change of the volume of the arterial pulsation causes the light transmittance to change. At this time, the photoelectrically reflected receiver receives the reflected light from the human tissue and converts it into an electrical signal to amplify and output it. Pin Description VIN: main power supply input, 1.8V-5V; 3-bit pad: Select the pull-up level of the bus, depending on the pin master voltage, select 1.8v or 3.3v (this terminal contains 3.3V and above) SCL: Clock connected to 12C bus SDA: Connect the data of the 12C bus, INT: interrupt pin of the MA×30102 chip; RD: RED LED ground terminal of MA×30102 chip, generally not connected; IRD: IR LED ground terminal of MA×30102 chip, generally not connected GND: Ground wire. Documentation, demo code, etc please see this wiki page.
