Function 21, subfunction 7 - set HD base.
The HD base defines hard disk to write with usage of obsolete
file system functions and functions implicitly using the hard disk
(such as subfunction 6 of function 18);
at usage of function 58 and 70 and modern syntax /HD0,/HD1,/HD2,/HD3
these function set base themselves.
Parameters:
- eax = 21 - function number
- ebx = 7 - subfunction number
- ecx = HD base: 1=IDE0, 2=IDE1, 3=IDE2, 4=IDE3
Returned value:
Remarks:
- Any application at any time can change the base.
- Do not change base, when any application works with hard disk.
If you do not want system bugs.
- To get HD base use subfunction 7 of function 26.
- It is also necessary to define used partition of hard disk by
subfunction 8.