Re: [Sheflug] New hardware confusion

[Peter Humphrey <prh@xxxxxxxxxxxxx>]

On Tuesday 24 July 2007 22:46, J Simpson wrote:

> Peter wrote:
> >Win 98 will only run on the primary disk on the first controller. You
> > could exchange the two hard drives, so that the original is the primary
> > and the new one is the secondary. You can probably do that with jumpers on
> > the disks. Then you may need to reinstall your boot manager.

> I don't think I understood any of the above (sadly).

Between the signal connector and the power connector on the end of your hard 
drive you should find a block of jumper pins. These determine whether the 
disk is to act as master or as slave, or whether the IDE signal cable will 
make the selection. You should also find a label on the top of the disk 
showing which is which.

Until recently, although IDE drives' jumpers could leave it to the signal 
cable connectors to determine which was primary and which secondary, in 
practice that didn't work because the cables, and the interfaces on the 
motherboards, didn't have the requisite conductors and logic, so we had to 
specify the master and slave manually. Sice the arrival of EIDE with its 
80-pin connectors, we can now allow the cable to make that choice - we just 
connect the black connector to the drive we want to be master and the grey 
one to the slave. And make sure the jumpers are left at CS (cable select).

Traditionally, each IDE interface has had two channels, one called master and 
the other slave. Most motherboards had two IDE interfaces, one called primary 
and the other secondary, allowing up to four devices to be attached. It 
became conventional to attach either one or two disks to the primary 
interface and either one or two optical drives (CD or DVD) to the secondary. 
This seems to be the arrangement you have now, with a third hard drive 
sitting on your desk.

Each hard drive was originally allowed up to four primary partitions (sorry 
about that name being used again) in which to hold a directory structure in 
which to store files, but only one of the four was visible to the operating 
system at any time. When that became insufficient, one of the four was 
allowed to be defined as an extended partition, in which up to 12 (SCSI) or 
15 (IDE) logical partitions could be defined, and all those would also be 
visible (the other two primaries would still be invisible though). That was 
the only purpose of an extended partition - it cannot store data itself, only 
hold and expose partitions. It's a fudge.

Windows 98 only worked reliably if it was in the first primary partition (i.e. 
at the beginning of the drive) on the master drive connected to the primary 
controller. I think later versions have allowed a bit more flexibility, but I 
haven't kept up except to say that Grub won't start XP unless XP is on the 
first partition.

> So I could disconnect my cd player, to temporarily use the connect for
> my old secondary drive to download the information?

That's what I had in mind, yes.

> Robin wrote:
> > What you propose sounds ok, the only problem may be because the 20g
> > drive has moved from primary to secondary or slave, win95 may see it D:
> > rather than as C: and so win95 will die.> 

I think this is wrong. Win 9x won't run at all unless it's on a primary 
partition on the master drive on the primary controller. It won't boot from 
anywhere else. Unless you know different...

> > As long as your drive has 2 ide channels you can usually run up to 4 ide
> > drives on one machine, so you'd have 3 harddrives and your dvd writer. 
> > However if you are still running 20g and 10g drives it sounds like your 
> > machine is an old one so it may only have a single channel.

No, this doesn't match what you wrote. It's clear that you have four devices 
connected.

> Hopefully my light bulb moment is coming soon.  Any further suggestions
> to clarify are all gratefully received.

HTH.

-- 
Rgds
Peter.
Linux Counter 5290, Aug 93

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