I have a question on the whole DOS IDE scan deal. How can you do a scan on the IDE bus after DOS is up and running? Here is my deal. I have a system that powers up my hard drive by what is called a 'power margined' solution. The drive is powered by an external source (not the computer's hard drive), but then can turn the drive on and off, or run the drive at different voltages. This is so I can do specific tests on the drive. However, there is a problem. The driver that turns power on to the drive does not load until DOS has pretty much loaded. So, when DOS does it's inital scan, the hard drive is turned off and so DOS does not see it. When it finally is turned on, it can be accessed from utilities that scan for the drive, but DOS still does not see it there. So general commands, like format, or fdisk, don't work because DOS doesn't know the drive is there. Is there a way (or utility) that you can re-scan the IDE bus and tell (or trick) DOS into finding the drive there? Thanks, Mike

Might try here... http://www.simtel.net/pub/msdos/diskutil/

The problem is, that DOS builds its control block structure for the drives and logical drives, and once done, can not go back and add space in the chain for an additional drive. So if the drive is not ready, space is not alocated, and the drive parameters are not read, so you are SOL. The second problem is that various parameters are read from the boot record and stored in these control blocks. That said, I could always find ways to trick DOS when I needed to with a little code. I doubt that any available utility exists that would do what you want. I know for a fact that this type of thing has been done many times, but all for special use. It sounds like you are trying to use some sort of tester, but do more by being able access the drive through normal DOS commands. It is possible to write code that would would make DOS think the drive is there and allow full access to it once it is ready. However, after doing a FDISK or FORMAT command, DOS would still have to be rebooted. And any such special code would have to know how the drive is formated. Tricky but can be done with a lot of work by someone.