Two options are suggested below:
1. MAXREFDES100 GUI allows the user to log the photoplethysmogram (PPG) and accelerometer data in a csv file (Logging -> Optical/Accel File Log). If your software or programming language has a way to open the csv file and extract the data, the raw data can then be processed. For example, MATLAB has the csvread function that can be used to open up csv files and extract the data. While processor intensive, you can call this function or something similar in your language environment repeatedly to get the latest data logged in the files. This can be useful if you want to process data in a real-time manner for algorithm development. If real-time processing is not required, you would only need to read the file once after you have finished logging the data.
2. A less processor intensive but much more complex alternative is to understand the packet structure of the data being sent by the Health Sensor Platform (HSP) and try to decode it as part of software/algorithm development.