In past days I've made the calculation of Min and Max of both IR and RED led signals.

I've also calculated R and today I've found a working oximeter to calibrate mine.

So, just updated the the code and completed the details.

Next step: make a complete schematic with all the parts since in the project there is also a LCD display 16x2 to show bpm, SpO2%, and some other informations, while the plot of the signals is made with the PC.