INT 33 - MS MOUSE v7.04+ - GET/SET BallPoint INFORMATION
        AX = 0030h
        CX = command
            0000h get status of BallPoint device
            other set rotation angle and masks
                BX = rotation angle (-32768 to 32767 degrees)
                CH = primary button mask
                CL = secondary button mask
Return: AX = button status (FFFFh if no BallPoint)
                bit 5: button 1
                bit 4: button 2
                bit 3: button 3
                bit 2: button 4
                other: zero
        BX = rotation angle (0-360 degrees)
        CH = primary button mask
        CL = secondary button mask