[ILUG] Header files and GPL

[Frank Duignan]

Morning all, I'm putting together a library of code for microcontrollers and
I've got to the stage where I need to worry about licenses.
The code involved runs on various devices and relies upon header files
supplied by manufacturers that define registers, bitmasks and so on.
Does this prevent GPL'ing of code?
Do I rewrite the header files?
Are register names copyright-able?
Thoughts?
f.