HP Vectra Technical Reference Manual page 437

S1D-BIOS Extension Functions
The STD-BIOS Functions Fnn_INQUIRE (6FOOH) indicate to the calling application that STD-BIOS
extension functions are loaded and have not been replaced. The STD-BIOS drivers listed in table
G.1 below support this function.
Table G.1
STD-BIOS Drivers That Support Fnn_INQUIRE
Interr'Jpt
INT 10
INT 14
INT 16
INT 17
Function
VIDEO
SERIAL
KEYBOARD
PRINTER
To find out if the STD-BIOS extensions for the Video driver are in place use the following code:
MOV AX, FlO_INQUIRE ,. Call video function (6FOO)
MOV
ax,
OFFFFH ; Make sure
ax
< >
'HP'
INT INT_ VIDEO ,. Interrupt 10H
eMP
ax,
'HP '
" Are video extensions present?
Jf VIDEO_fXTENSIONS_PRESENT
VIDEO_fXTENSIONS~OT
_PRESENT:
VIDEO_EXTENSIONS_PRESfNT:
G.4.2 Obtaining Memory From the EX-BIOS
The system allows EX-BIOS drivers to obtain limited amounts of memory independent of the
operating system. This feature is especially important for I/O ROM adapters since their cost can
be reduced if they do not require dedicated RAM. When the I/O ROM module is initialized,
it
can
ask for EX-BIOS memory.
428 Driver Writer's Guide