Format of IBM/MS INT 13 Extensions drive parameters |
| Offset | Size | Description |
|---|---|---|
|
00h |
WORD |
(call) size of buffer (001Ah for v1.x, 001Eh for v2.x, 42h for v3.0) |
| (ret) size of returned data | ||
|
02h |
WORD |
information flags (see #00274) |
|
04h |
DWORD |
number of physical cylinders on drive |
|
08h |
DWORD |
number of physical heads on drive |
|
0Ch |
DWORD |
number of physical sectors per track |
|
10h |
QWORD |
total number of sectors on drive |
|
18h |
WORD |
bytes per sector |
|
--- v2.0+ --- |
||
|
1Ah |
DWORD |
 configuration
parameters (see #00278)
FFFFh:FFFFh if not available |
|
--- v3.0 --- |
||
|
1Eh |
WORD |
signature BEDDh to indicate presence of Device Path info |
|
20h |
BYTE |
length of Device Path information, including signature and this byte (24h for v3.0) |
|
21h |
3 BYTEs |
reserved (0) |
|
24h |
4 BYTEs |
ASCIZ name of host bus ("ISA" or "PCI") |
|
28h |
8 BYTEs |
ASCIZ name of interface type
|
|
30h |
8 BYTEs |
Interface Path (see #00275) |
|
38h |
8 BYTEs |
Device Path (see #00276) |
|
40h |
BYTE |
reserved (0) |
|
41h |
BYTE |
checksum of bytes 1Eh-40h (two's complement of sum, which makes the 8-bit sum of bytes 1Eh-41h equal 00h) |
|
Note: |
If the size is less than 30 on call, the final DWORD will not be returned by a v2.x implementation; similarly for the Device Path info. |
|
See Also: |