GM MDI canbus logger
This is some code to log the data on the high speed canbus.. You would use this with an OBD2 splitter cable and an MDI(or possibly any J2534 device) and either another MDI or some other OBD2 device that talks to the vehicle.. You could monitor scan tool commands and programming data,etc.. Instructions for use are part of the program, it's a very simple command line program.. It's rough but it seems to work just fine..
I did use example code and dll from https://github.com/BrianHumlicek. Hopefully I did include the correct copywrite information in the code and also here.. Let me know of any issues, I am new at this, might be able to fix it, but might not.. I will try..