Format of XGA subsystem information |
| Offset | Size | Description | ||||||
|---|---|---|---|---|---|---|---|---|
|
00h |
DWORD |
pointer to null-terminated board OEM string | ||||||
|
04h |
DWORD |
capabilities (see #00072) | ||||||
|
08h |
DWORD |
pointer to 8KB XGA ROM (or NULL) | ||||||
|
0Ch |
DWORD |
pointer to the XGA memory mapped registers | ||||||
|
10h |
WORD |
base address of XGA I/O registers (21x0h) | ||||||
|
12h |
DWORD |
pointer to start of physical video memory (A000h:0000h or B000h:0000h) | ||||||
|
16h |
DWORD |
physical address of 4MB aperture (or NULL if none) | ||||||
|
1Ah |
DWORD |
physical address of 1MB aperture (or NULL if none) | ||||||
|
1Eh |
DWORD |
physical address of 64KB aperture (or NULL if not enabled) | ||||||
|
22h |
DWORD |
physical address of OEM aperture (or NULL if none) | ||||||
|
26h |
WORD |
size of OEM aperture in 64KByte units | ||||||
|
28h |
DWORD |
pointer to list of video modes. The list is a series of WORDs terminated by FFFFh | ||||||
|
2Ch |
WORD |
number of 64KB blocks on the board | ||||||
|
2Eh |
DWORD |
XGA manufacturer ID
|
||||||
|
32h |
206 BYTEs |
reserved |