Function 62, subfunction 1 - get number of the last PCI-bus.
Parameters:
- eax = 62 - function number
- bl = 1 - subfunction number
Returned value:
- eax = -1 - access to PCI is disabled; otherwise
- al = number of the last PCI-bus; other bytes of eax are destroyed
Remarks:
- Previously low-level access to PCI for applications must be
enabled by subfunction 12 of function 21.
- If PCI BIOS is not supported, the value of ax is undefined.