The open source repository does not include the implementation of the functions declared in signals.h and these are required to compile and program a vehicle interface. These functions are dependent on the specific vehicle and message set, which is often proprietary information to the automaker.
If you cannot use a pre-built binary firmware from an automaker, you can either:
- Recommended: Create a VI configuration file and use the code generation tool in the OpenXC Python library. Many examples of configuration files are included in the docs, as well as a complete reference for all configuration options.
- Implement the functions in signals.h manually. Knowledge of the vehicle’s CAN message is required for this method. The documentation of those functions describes the expected effect of each. Implement these in a file called signals.cpp and the code should now compile. The configuration file method is strongly recommended as it still allows flexibility while removing boilerplate.
Knowledge of the vehicle’s CAN messages is required for both options - this is advanced territory, and if you’re just looking to get some data out of your car you most likely want one of the binary firmwares from an automaker