CPU Layer
μC/CAN can work with either an 8, 16, 32 or 64-bit CPU but, needs to have information about the CPU you are using. The CPU layer defines such things as the C data type corresponding to 16-bit and 32-bit variables, whether the CPU is little or big endian and, how interrupts are disabled and enabled on the CPU, etc.
CPU specific files are found in the \uccpu directory and, in order to adapt μC/CAN to a different CPU, you would need to either modify the cpu*.* files or, create new ones based on the ones supplied in the uccpu directory. In general, its easier to modify existing files because you have a better chance of not forgetting anything.