Int 16 Fn 6F0F  - Hp Vectras Rs/20c And Rs/25c - Enable Memory Caching     [b]

   AX = 6F0Fh

Return: AH = status
       00h successful
       FEh cache subsystem is bad

See Also: AX=6F00h,AX=6F10h,AX=6F11h