What are the IR/Red Samples and how does it relate to the raw LED data

Sensors Biometrics
1

On the “SparkFun Pulse Oximeter and Heart Rate Sensor - MAX30101 & MAX32664 (Qwiic)” board here:

https://www.sparkfun.com/products/15219

For the arduino code body.irLED, what does this mean. According to the following guide:

https://learn.sparkfun.com/tutorials/sp … r-settings

body.irLed = Number of IR LED Samples. However, when I plot this data I do not get my expected PPG signal (the raw signal from the LED data)

The first thing I notice, is that the signal may be upside down, which makes sense as it is reflection not transmission PPG. However, what I notice is that the derivative of body.irLed appears to be more like the expected PPG signal over the body.irLed.

My question is: what is the body.irLed in terms of the raw Led data/raw PPG waveform.

2

Pages 28-29 here https://github.com/sparkfun/SparkFun_Bi … x32664.pdf make me believe it’s Default is to ignore ADC calibration and use the default 'ppg_cfg1" as the calibration/look-up table; use a different setting (also detailed on the same pages) to swap that for a custom mode and/or calibrated against your use-case