vhdl-highlight-case-sensitive

vhdl-highlight-case-sensitive is a variable defined in `vhdl-mode.el'.
Its value is

nil

Documentation:
Non-nil means consider case for highlighting.
Possible trade-off:
non-nil also upper-case VHDL words are highlighted, but case of words with
special syntax is not considered
nil only lower-case VHDL words are highlighted, but case of words with
special syntax is considered
Overrides local option `font-lock-keywords-case-fold-search'.

NOTE: Activate the new setting in a VHDL buffer by re-fontifying it (menu
entry "Fontify Buffer").

You can customize this variable.