question about scsi device?

It seems not many foucs on scsi device...
Please give me a hand anyway.

As we know , a scsi device like CD-ROM has its HostID, TargetID and LUN ID. I want to get the three IDs in win98.
Till now I find a way, but it should use ASPI interface: TranslateAspiAddress.  But the detail of the method is very complex.

Does anybody know how to get the three IDs without ASPI, given the CD-ROM symbol such as \"G:\" or \"K:\"

Or in another simpler way, If I give the three ID, How can I get its Devnode?

Thanks for advance!