As I had search for such file to configure LinuxCNC and didn't find it on the WEB I did it quickly for my personal tasks and shared it to the WEB. You are free to add\change and do any other changes you think you need without restriction except those that stated in license GNU GPL v3.
The installation guide text was get from http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Highlighting_In_Vim
Original Author Pavel Ruban http://pavelruban.org
Screenshot
Installation
make yourself a ~/.vim/ directory make a syntax directory in there save upload:linuxcnc-hal.vim into ~/.vim/syntax/ save upload:filetype.vim into ~/.vim/ (or merge with your existing one, if any): open, or restart vim open any files with *.hal extensions, and it should auto-highlight them
You can also force highlighting with:
:set syntax=linuxcnc-hal