Externally connecting internal IDE drives

Do you have a question? Post it now! No Registration Necessary

Translate This Thread From English to

Threaded View
I have a very large and complex rack-mounted box which contains a 14-slot
ISA bus passive backplane [physically divided into 2 separate PC segments]
and 12 cards of various sorts installed.  The box has physical room for
mounting 3 drives in the front opening in which I have a floppy and 2
removable HD frames for one of the PC's and I have internally mounted a
permanent HD and made a cutout in the back panel for a floppy for the second
PC in the box. Everything works well ... Until I need to attach a CDROM
drive to one of the PC's.  Currently I've got the cables from the secondary
IDE controllers and a power cable hanging outside the box and I simply hang
a CDROM drive (or a temporarily needed HD) from the cables.  That's ugly
and, even though it's a very low traffic area, still quite unstable and
probably unsafe as well.

SO .. Does anyone know of a reasonable way to "mount" IDE internal HDs &
CDROMs externally?

    TIA
        Norm


Re: Externally connecting internal IDE drives
Quoted text here. Click to load it
You could attach a USB, firewire, or SCSI drive.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam.  Our true address is of the form snipped-for-privacy@prodigy.net.

Re: Externally connecting internal IDE drives

Quoted text here. Click to load it

-USB mass storage
-network mapped
-lots of superglue

Pozdrawiam.
--
RusH   //
 http://randki.o2.pl/profil.php?id_r35%2019
We've slightly trimmed the long signature. Click to see the full one.
Re: Externally connecting internal IDE drives
Quoted text here. Click to load it

Use the same circuit the external USB/Firewire boxes use. It converts
USB and/or Firewire to IDE. You probably need a dedicated cisrcuit for
each drive. Then you can use a USB or Firewire cable to connect to your
PC. The drives can even be hot-plugged (is four power-supply allows).

Markus

Re: Externally connecting internal IDE drives
Norm

Quoted text here. Click to load it
You can still get removable IDE drive cases "caddys" where you mount a 3.5"
drive in a 5.25" case. Some of these are hot-swappable although that does
depend on which OS you are using...

That would work for the hard discs. CD-ROMs are more problematic: USB or
Firewire as others have suggested would probably be best. Try googling for
hot swap cd drive.

    Andrew



Re: Externally connecting internal IDE drives

Quoted text here. Click to load it

Please note there isn't really any such thing as an "internal"
IDE/ATAPI device --- they're all internal by definition.  The only
question to decide upon is "internal to _what_?"  The design assumes a
PC or something like it, but there are alternatives, most prominently
in the form of separate boxes that hold an ide drive and connect it to
something else.

The big problem is an electrical one: IDE/ATAPI is not at all designed
to be hot-swappable, and not particularly friendly with the concept of
external mounting.  Note that there's not even a standardized plug for
external IDE cables --- the allowed cable length of about 80 cm (40 cm
in some cases) would make any non-neglible amount of external cable a
fragile concept anyway.

My recommendation would be to forget about using IDE itself as the
attachment method for those movable drives.  Use USB, Firewire, or
ethernet instead.

--
Hans-Bernhard Broeker ( snipped-for-privacy@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

Re: Externally connecting internal IDE drives
Quoted text here. Click to load it

Alas, there are several problems with using any other attachment than IDE
for the drives I want to use:
    1.  I have to be able to boot and run a variety of OS on each of the
computers including standard MS-DOS which doesn't (natively) support USB,
Firewire, or Ethernet.  As a general rule, if I need to attach something
external, it has to be IDE here.

    2.  I have to be able to (re)install OS like Linux and Windows onto the
actual removable drives that are housed in the drive carriers.  Neither of
these OS installation programs support USB or Firewire.  Ethernet to another
PC on the network is possible, though not necessarily easy nor reliable

    3.  I'm not looking for hot-swappability, but simple reconfigurability
from time to time for almost exclusively attaching a CD-ROM drive -- though
on a very few occasions I've needed to attach a secondary HD so I could do a
drive copy.

I have, in each of the four rackmount chassis that I have, installed
removable HD carriers and have several (boot) drives for each computer that
simply slip in and out [with power off, of course].  This takes care of the
basic HD's, but attaching a CD-ROM drive from time to time is then
problematic.  I suppose I could install a SCSI card in each box and use an
external SCSI CDROM drive I have, but I don't always want to have SCSI part
of the computer configuration because I'm trying to match the exact setup of
various embedded systems for which I've developed and for which I write and
maintain software.

The removable HD sleds connect to their frames with just 50-pin Centronix
connectors which carry both the normal 40-pin complement of IDE signals and
the power and ground.  I've tried using a commercial SCSI cable to allow one
of the sleds to be external to the frame but the computer wouldn't boot with
it installed and I'm pretty sure it's because the cable manufacturer is
taking shortcuts and running fewer than 50 wires by using a common ground
wire or two in place of the several in the normal SCSI configuration.  I
haven't been able to find any compatible cables made with ribbon cable where
I could be guaranteed of 50 separate wires.  If anyone knows of a source of
50-wire ribbon cables with one each male and female 50-pin Centronix
connectors, I'd be very grateful because I think that this would solve my
problem.

    Norm


Re: Externally connecting internal IDE drives
On Monday, in article

Quoted text here. Click to load it
.......

Well it is possible to create a Boot ROM for network cards so it could boot
off a remote system via Ethernet and the ethernet can be supported under
DOS. Boot ROM could detect if the controller has a physical link to
establish if it should carry on or relinguish control back to the BIOS
to boot harddrive(s).

USB can be supported under SOME newer DOS variants (as used by Norton Ghost).

Quoted text here. Click to load it

Ethernet would be easier and cope with longer distances.

Quoted text here. Click to load it

That is extra support and back configuration that may be awkward.

Quoted text here. Click to load it

WHY??

Why put a SCSI cable onto a connector configured to drive IDE/ATAPI?
You may have exceeded distances for drive, let alone the fact that the
interfaces could be wired differently so ground/power commoning could mess
up the signals. Also the power may have been going down insufficient
conductor size causing power drops.

Quoted text here. Click to load it

I am pretty sure it is because you used lipstick as superglue.

Quoted text here. Click to load it

At one site several years ago a class was setup for doing imaging training
and to ensure the students did not load any nastys, I made up for the
customer several cables to take the floppy interface from the motherboard
to a connector mounted on a blanking plate. Added to the cable several power
and ground conductors. Then made a box with a floppy drive and a SHORT cable
to a connector. This way at the time any boot/driver floppies could be
loaded by the administrator.

If the following conditions can be met

        1/ CD-ROM is the ONLY device on the secondary IDE interface,
  AND   2/ all your motherboards have Primary AND SECONDARY IDE interfaces,
  AND   3/ At least one spare slot on ALL target systems
           within SHORT distance from SECONDARY IDE interface connector

Then consider making a SHORT internal cable to blanking plate connector
of many pins, with MANY pins also assigned to take the power and ground.
Get a USB 5.25" USB CDROM empty case, and modify it to take a cable to
mate with the other connector as 1-1 connection all separate wires.
Make the cable SHORT to keep the distance of cable less than a normal
IDE cable length about 14inches or less.

CDROM will always be behind the unit, ensure the unit will be supported
and not hanging on the cable, or make a bracket to hold the CDROM box.

If necessary use 50pin Centronics connectors I am sure you could probably
buy pre-punched blanking plates that will take a 50pin Centronics connector.
You only need a couple for the box end (keep a spare or two), and at least
one of the opposite type for the computer ends

--
Paul Carpenter          | snipped-for-privacy@pcserviceselectronics.co.uk
<http://www.pcserviceselectronics.co.uk/ PC Services
We've slightly trimmed the long signature. Click to see the full one.
Re: Externally connecting internal IDE drives

Quoted text here. Click to load it

DOS doesn't have to.  Modern BIOSes can, at least in principle, boot
off just about any USB device that reports itself as a harddisk.  Some
people have been known to keep a Linux system image on digital cameras
or MP3 players, just for the perverse fun of it...

Quoted text here. Click to load it

That's not particularly much harder with a disk mounted in an external
USB box than with one mounted in a IDE quick-switch carrier.  Rip the
HD out of the box, put it into your PC as a secondary, and that's
that.  For Linux, you can even leave it in the box -- just attach it
and install Linux onto it.

Quoted text here. Click to load it

At least for Linux, I must object to this statement.  Linux (given the
right distribution) installs onto pretty much anything you want, if
you know a bit more than how to do the three mouseklicks for the
vanilla default installation.

Quoted text here. Click to load it

What's stopping from building those cables yourself?

--
Hans-Bernhard Broeker ( snipped-for-privacy@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

Re: Externally connecting internal IDE drives

Quoted text here. Click to load it

    I haven't been able to find any 50-pin Male and Female Centronix IDE
connectors.  Since I have a medical problem with my hands, I'm not likely to
succeed in using solder-cup connectors -- IDE are a must.  If you know of a
source, I'd be very grateful.

    Norm


Re: Externally connecting internal IDE drives

Quoted text here. Click to load it

The things you're talking about here are not "IDE connectors" ---
they're just plain old press-on connectors for ribbon cable.  I doubt
such connectors exist in Centronix form --- the pitch of those plugs
would appear too different from standard ribbon cable.

--
Hans-Bernhard Broeker ( snipped-for-privacy@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

Re: Externally connecting internal IDE drives
Quoted text here. Click to load it
likely to

He was probably referring to IDC connectors, which is the correct name for
connectors like the ones on IDE and SCSI harddisks, floppy drives etc.

Meindert



Re: Externally connecting internal IDE drives
Quoted text here. Click to load it
IDE

    Yup, sorry about that.  I was tired when I wrote that and since IDE is a
valid acronym it got past my proofreading.

        Norm


Re: Externally connecting internal IDE drives

Quoted text here. Click to load it

The Centronix style IDC connectors do exist. I haven't looked for a 50 pin
version but if they are done at that number of pins then I am sure they
should be findable. Try Farnell, RS or your local decent electronics
suppliers. I have the standard printer Centronix plugs in IDC style plugged
into my printer at present.

--
********************************************************************
We've slightly trimmed the long signature. Click to see the full one.
Re: Externally connecting internal IDE drives
Quoted text here. Click to load it


USB 2.0 is fast, hot-socketable, Win XP compatible, and the interface
from IDE to USB is pretty cheap (<$20?).

Site Timeline