Int 33/AX=6F00h

AX = 6F00h
BX <> 4850h

Return:
BX = 4850h ('HP') if mouse driver written by Hewlett Packard

See Also: INT 10/AX=6F00h - INT 14/AX=6F00h - INT 16/AX=6F00h - Category: Mouse/Pointing Device - Int 33h - H