INT 15 - SYSTEM - POINTING DEVICE BIOS(Basic Input/Output System) A set of standardized calls giving low-level access to the hardware. The BIOS is the lowest software layer above the actual hardware and serves to insulate programs (and operating systems) which use it from the details of accessing the hardware directly. INTERFACE (PSIBM PS/2, any model) - EXTENDED COMMANDS AX = C206h BH = subfunction 00h return device status Return: BL = pointing device status (see #00524) CL = resolution (see #00523) DL = sample rate, reports per second 01h set scaling at 1:1 02h set scaling at 2:1 Return: CF set on error AH = status (see #00522) Bitfields for pointing device status: Bit(s) Description (Table 00524) 0 right button pressed 1 reserved 2 left button pressed 3 reserved 4 0 if 1:1 scaling, 1 if 2:1 scaling 5 device enabled 6 0 if stream mode, 1 if remote mode 7 reserved