Function 21, subfunction 3 - set CD base.
Parameters:
eax = 21 - function number
ebx = 3 - subfunction number
ecx = CD base: 1=IDE0, 2=IDE1, 3=IDE2, 4=IDE3
Returned value:
eax = 0
Remarks:
CD base is used by function 24.
To get CD base use
subfunction 3 of function 26
.