INT 1A - PCI 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. v2.0c+ - READ CONFIGURATION DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address. (VLSI devices)
	AX = B10Ah subfn 1004h
	BH = bus number
	BL = device/function number (bits 7-3 device, bits 2-0 function)
	DI = register number (0000h-00FFh) (see #00878)
Return: CF clear if successful
	    ECX = dword read
	CF set on error
	AH = status (00h,87h) (see #00729)
	EAX, EBX, ECX, and EDX may be modified
	all other flags (except IF) may be modified
Notes:	this function may require up to 1024 byte of stack; it will not enable
	  interrupts if they were disabled before making the call
	the meanings of BL and BH on entry were exchanged between the initial
	  drafts of the specification and final implementation
SeeAlso: AX=B10Ah,AX=B10Ah/SF=8086h


Format of PCI Configuration Data for VLSI VL82C591 Host/PCI bridge:
Offset	Size	Description	(Table 00919)
 00h 64 BYTEs	header (see #00878)
		(vendor ID 1004h, device ID 0005h)
 40h	BYTE	bus number
 41h	BYTE	subordinate bus number
 42h	WORD	reserved
 44h  4 DWORDs	reserved
 54h  2 BYTEs	device-specific configuration registers
 56h	WORD	reserved
 58h  2 BYTEs	device-specific configuration registers
 5Ah	WORD	reserved
 5Ch  5 BYTEs	device-specific configuration registers
	...
 FFh	BYTE	device-specific configuration register
SeeAlso: #00878,#00732,#00920


Format of PCI Configuration data for VLSI VL82C593 PCI/ISA(Industry-Standard Architecture) The expansion bus used by the IBMInternational Busiuness Machines PCIBM PC/ATIBM PC AT.  See also EISA. bridge:
Offset	Size	Description	(Table 00920)
 00h 64 BYTEs	header (see #00878)
		(vendor ID 1004, device ID 0006h)
 40h  4 DWORDs	reserved
 50h 11 BYTEs	device-specific configuration registers
 5Bh	BYTE	reserved
 5Ch 25 BYTEs	device-specific configuration registers
 75h 138 BYTEs	reserved
 FFh	BYTE	device-specific configuration register
SeeAlso: #00878,#00919