INT 0x15 - 0xc0 - Return System Configuration Parameters (PS/2 only)

Request/Call:

reg	value	descr
AH	0xc0

reg	descr
AH	set, 80h for PC & PCjr, 86h for XT (BIOS after 11/8/82) and AT (BIOS after 1/10/84)
ES:BX	pointer to system descriptor table in ROM of the format (see below)

offset	size	description
00h	word	length of descriptor (8 minimum)
02h	byte	model byte (same as F000:FFFE, not reliable)
03h	byte	secondary model byte
04h	byte	BIOS revision level (zero based)
05h	byte	feature information, see below
06h	dword	reserved

bit	description
0	reserved
1	0=PC Bus 1=Micro channel
2	Extended BIOS Data Area (EBDA) allocated
3	wait for external event supported
4	INT 15,4F used (kbd intercept)
5	RTC present
6	2nd 8259 present
7	DMA channel 3 used by fixed disk BIOS