There are two thing here:
As I understand it, you can't just call any comp, even if you have a file named that on your pc. It has to be complied into your LinuxCNC build. We can call "and" , "trivkins" , "hostmot2" etc as these are compiled into the main LinuxCNC build by the admins. If you do your own comp, you have to compile it from its collection of .c and .h files on your PC, and then you can call the comp from your HAL.
If you took my HAL and changed pin names from e.g "mh400e-gearbox.spindle-speed-out" to "FP4-gearbox.spindle-speed-out" it will error out, as that pin does not exist. The comp creates the pins, and those names are hard coded in the "mh400e_common.h" file where these pins are defined. So you will need to go through the code and rename each pin and each instance of it's use in the various .c anc .h files, and then recompile it with your naming convention.
Cheers,
Mark
