MHDD : can it access USB-connected, 4k-sectored disks ?

[Czerno]

Hi, respected Gurus !

Am reluctantly entering the 21st century - got a new IOMEGA "Prestige" storage appliance, 1 Terabyte, USB 3, black case.

The thing works as advertised in Windows XP/2k (with latest service packs) and also under reasonably recent Linuces, but much to my disappointment not in DOS or Windows 98 SE(My previous appliance was a good old 80 Gbyte worth of data and had no problems with DOS or Win 9x) .

In order to sort things out I dnloaded and ran the latest MHDD 4.6 + USBASPI.SYS.

MHDD can id the disk but, sadly, hangs forever when asked to read sectors (TOF or CX commands).

The id command does return :
OEM Ext Hard Disk
LBA: 244011445
Unit Size : 4096 bytes

... My guess is that this unit is AF-4096 with no 512-byte sector emulation whatsoever :=( I didn't think such things were made or sold already

Bunch of questions :

Is the MHDD freeze expected ? If so, any new version coming that will work with "big" sectors ?

What other (free, or free for trial at least) DOS diagnostic software does work with such drives ?

Any software solution (BIOS emulation, DOS & Windows 9x drivers) can make the thing usable on "legacy" OSes ?

Sadly the industry is pushing this new cr@p on us without regard to people who must, or want to, keep older hard/soft running !

TYIA

--
Czerno

[fzabkar]

AIUI, the drive inside the enclosure is probably still emulating 512-byte LBAs, even if it is an Advanced Format model. You could verify whether this is the case by using a utility such as CrystalDiskInfo or smartctl to retrieve the Identify Device data directly from the drive. I'm not sure, but I suspect that MHDD may be using SCSI commands to retrieve the ID information from the USB mass storage device rather than from the drive itself.

The following document provides an insight into the relevant SCSI commands.

Universal Serial Bus Mass Storage Specification For Bootability:
http://www.usb.org/developers/devclass_ ... ot_1.0.pdf

FWIW, I know that WD's and Seagate's 3TB drives still use 512-byte emulation. However, when placed inside a GoFlex or My Book external enclosure, these USB mass storage devices report 4KB LBAs. In these cases the USB-SATA bridge IC handles the 512B-4KB translation. I believe that WD and Seagate choose this method in order to maintain plug-in compatibility with Windows XP. That said, it would seem strange for a 1TB drive to be configured in this way, as it would not be subject to the same 2TiB MBR limitation.

FYI, here is an alternative solution to the 2TiB limit:
http://www.tomshardware.co.uk/forum/274 ... ws-devices

Verbatim configures the bridge firmware to present a 3TB drive as two smaller physical drives, each with 512-byte LBAs. A JMicron firmware update allowed the OP in that thread to reconfigure his USB mass storage device as a single 3TB drive with 512-byte LBAs. Perhaps that could be a solution for you?

BTW, I'm also still using Win98SE.

[Czerno]

AIUI, the drive inside the enclosure is probably still emulating 512-byte LBAs, even if it is an Advanced Format model. You could verify whether this is the case by using a utility such as CrystalDiskInfo (...)

Wow! That is a nice, free, powerful utility! Thanks for the tip about Crystal.
Here's the excerpted report,
----------------------------------------------------------------------------
CrystalDiskInfo 4.1.3 (C) 2008-2011 hiyohiyo
(2) Hitachi HDS721010CLA332 : 1000.2 GB [1-X-X, sa1] (V=059B, P=0070)
Enclosure : oxSATA OEM Ext Hard Disk (JP9960HZ1EJ51U) [UPT] (V=059B, P=0070, sa1)
# of Sectors : 1953525168
Rotation Rate : 7200 RPM
Interface : USB (Serial ATA)
Features : S.M.A.R.T., APM, 48bit LBA, NCQ
----------------------------------------------------------------------------

... I can't find in the Crystal report where it tells of sector size, but Hitachi http://www.hitachigst.com/internal-drives/advanced-format-drives website says all their models indeed emulate 512 bytes sectors, as you implied.

Hitachi has an alignment utility for these drives. Will that work through the USB interface too ? I won't remove the disk from its enclosure, if for no other reason that I don't own MoBos equipped with SATA ;=)

And, oh: please, what the devil is the NCQ feature reported by Crystal ?

I suspect that MHDD may be using SCSI commands to retrieve the ID information from the USB mass storage device rather than from the drive itself.

You are most certainly right. MHDD uses the ASPI to talk to a DOS driver (USBASPI.SYS) which emulates SCSI.

FWIW, I know that WD's and Seagate's 3TB drives still use 512-byte emulation. However, when placed inside a GoFlex or My Book external enclosure, these USB mass storage devices report 4KB LBAs. In these cases the USB-SATA bridge IC handles the 512B-4KB translation. I believe that WD and Seagate choose this method in order to maintain plug-in compatibility with Windows XP. That said, it would seem strange for a 1TB drive to be configured in this way, as it would not be subject to the same 2TiB MBR limitation.

Strange indeed, and really hostile to us legacy system users !

(snip)

BTW, I'm also still using Win98SE.

Excellent, bro!

--
Ninho

[fzabkar]

Page 16 of the following document confirms that the physical sector size is 512 bytes.

Hard Disk Drive Specification, Hitachi Deskstar 7K1000.C, Ultrastar A7K2000, CinemaStar 7K1000.C:
http://www.hitachigst.com/tech/techlib. ... ec_1.0.pdf

In any case you could have determined this from the number of sectors reported by the drive:

capacity = 1953525168 sectors x 512 bytes per sector = 1 000 204 886 016 bytes

Interestingly, when the same calculation is performed using 4KB LBAs, we get ...

244011445 LBAs x 4096 bytes per LBA = 999 470 878 720 bytes

That's a difference of 734,007,296 bytes. Therefore I suspect that you may have one of those external products that incorporate a Virtual CD (similar to WD's SmartWare).

As for your alignment concerns, since the mass storage device is being accessed using 4KB LBAs, then it stands to reason that any Advanced Format drive behind the bridge would be automatically aligned. Perhaps that's the reason that Iomega chooses to do it this way???

Finally, your question regarding NCQ is answered here:
http://en.wikipedia.org/wiki/Native_Command_Queuing

[Czerno]

>In any case you could have determined this from the number of sectors reported by the drive:

Why, yes, I did, I can read too :=)

> (snip) I suspect that you may have one of those external products that incorporate a Virtual CD

Correct, the drive was shipped with an encryption-setting utility in a CDFS partition (which I since have deleted).

>As for your alignment concerns, since the mass storage device is being accessed using 4KB LBAs, then it stands to reason that any Advanced Format drive behind the bridge would be automatically aligned. Perhaps that's the reason that Iomega chooses to do it this way???

Makes sense. But it's an aggravation for us DOS/Windows 98 users :=(
I wish Iomega provided a Win 98 driver, I'll mail their support departmùent (not that I think they'll care much)
Also, I think I tracked the makers of the USB to SATA bridge on the web, I will try to confirm and may email them. Maybe their chips are configurable and could be set to pass 512 bit sectors through.

> NCQ

Good link (Google found it too). Queuing requests and reordering operations, an interesting concept that is indeed

Thanks again. If you find hints of workarounds for DOS and/or WinDOS, please do share !
I am aware of (non free) DOS patches by a Rudolf Loew for supporting 4k sectors, not sure if they would work with USB drives.

[Vulcan]

Sadly the industry is pushing this new cr@p on us without regard to people who must, or want to, keep older hard/soft running !

Without wanting to sound unnecessarily harsh, an alternative way to view this is that the industry is always moving forwards, and those people who stay on older, unsupported, OS versions cannot assume that new devices will be backwardly compatible. If the manufacturer didn't state Win98 support, then you bought this device at your own risk.

I don't ask you to agree with my view, but I've seen a few (mainly small) corporate users over the years, who didn't understand this cost to staying on old OS versions, and who needed "educating" about this. However most of them do understand, and plan for, OS transitions when their current version becomes obsolete. People staying on old Linux versions have similar problems, and old Unix versions, and Windows 3.x, and ... IMHO the trend should be clear by now

There seems to be a simple solution, and this is what I would do in your situation:

got a new IOMEGA "Prestige" storage appliance, 1 Terabyte, USB 3, black case.

For 1TB drives, several external drives (with USB2 interfaces) are still available which are "Win98-compatible" (although not supported as such by the manufacturer) i.e. they have standard 512 byte sectors. If your chosen one does not come with a manufacturer-provided Win98 driver, then either use one of the generic Win98 Mass Storage drivers, or use a Win98 Mass Storage driver from a different manufacturer and "persuade it" that your drive is supported.

You could buy one of those "Win98-compatible" 1TB drives, and sell your existing Iomega drive - on eBay if nowhere else (or, request an exchange if your point-of-sale allows that). This path might be easier for you, than trying to fix the lack of 4kB sector support in old OS.

Even if you don't like my reply above, at least it'll be searchable for other people in future

[Czerno]

if you don't like my reply above, at least it'll be searchable for other people in future

I do appreciate your reply, Vulcan.

You could buy one of those "Win98-compatible" 1TB drives, and sell your existing Iomega drive - on eBay if nowhere else (or, request an exchange if your point-of-sale allows that). This path might be easier for you, than trying to fix the lack of 4kB sector support in old OS.

Where I live things are more complicated. Whatever... I'm keeping the appliance, to use primarily as local backup, and additional storage medium for Windows XP on the computer to which it is attached. If I could resolve the 4k-sector problem it would add two more uses for the device, viz file access from any OS - I multi-multi-boot :=) - and fast exchange of data with other computers that don't "do" XP or modern *X. (my home LAN is powerline based, the old and slower version) Sad it won't quite do what I expected but non essential for me.

most ... do understand, and plan for, OS transitions when their current version becomes obsolete.

Understood but... this is a case of unnecessary obsolescence - forcing 4k sector access (thru the USB) while the disk itself is under 2 GiB and has legacy physical sector size. I had not owned a disk more than 80 GB before, I couldn't imagine such perversion

Thx and have good days...

[Vulcan]

this is a case of unnecessary obsolescence

Perhaps - but from my work in product development (though not for Iomega), I can think of another reason for that decision, which has a sound justification.

For every complex problem there is an answer that is clear, simple, and wrong.
[H. L. Mencken]

I'm keeping the appliance, to use primarily as local backup, and additional storage medium for Windows XP on the computer to which it is attached.

I'm glad you've reached a conclusion on this. Good luck

[Czerno]

from my work in product development...

now you have me intrigued... being an insider can you tell why there couldn't be either a physical switch (and/)or software for disabling sector size translation by the bridge ? Everybody would win, vendors could advertise their products for compatibility to more OSes.


Hopefully it /is/ possible already, just not advertised to end consumers ? Or at least a firmware upgrade could change the behaviour. You can lookup the reference of the chip used on this Iomega appliance (cf. above Crystal report). I'm sure you identified the company which makes that chip, would you have or could you find programming documentation for that device ?

[Vulcan]

Everybody would win

There are hidden costs too - it's not necessarily a win/win to do as you suggest, especially if the incremental extra market (i.e. obsolete OS) is deemed to be insignificantly small by the manufacturer. Been there, done that. There's lots more I could say about this type of situation, but it wouldn't alter the problem you have, so it isn't worth going into that now.

would you have or could you find programming documentation for that device

I don't work on this type of device, but on other data storage equipment.

[Czerno]

OK, thanks. I'll try to contact PLX Tech support and with some luck they'll tell me whether what I have in mind is feasible. With even more luck they might send a utility :=)
More probably they'll send me back to Iomega, or not reply at all : I'm philosophically prepared in every case.

- for your and other interested readers' information, the IC in question is that one, I presume :
http://www.plxtech.com/products/consumer/oxu3111

[fzabkar]

PLX Tech acquired Oxford Semiconductor. Your device appears to be a modern development in that stable.

ISTR that in the past I was able to download generic firmware updates from PLX Tech for their own bridges, but I can't see anything like that now.

BTW, finding anything for Win98 these days is a real challenge. However, there are some very good resources which are maintained and supported by some old diehards.

Here are two of them:
http://www.msfn.org/board/complete_list ... 84886.html
http://www.mdgx.com/spx/

The following newsgroup still has active participants:
microsoft.public.win98.gen-discussion

[Czerno]

PLX Tech acquired Oxford Semiconductor. Your device appears to be a modern development in that stable.

Yep, I noticed that. The devices' generic name being a telltale "oxbridge".

PLX has all the doc for download, but requires signing an NDA which they might not grant the opportunity to me average Joe. I'll try to email their tech support all the same, they might provide some useful information. Another route, I'll contact Hiyohiyo (CrystalDiskInfo author), in the hope that /he/ got the neceassary information either from Oxford/PLX or from reverse engineering.

BTW, finding anything for Win98 these days is a real challenge.

Actually what I hope to be able to do is not Windows 98 specific at all, it would be reprogramming the device (bridge) once and for all (alternatively, every time it was booted) so it passes 512 bit sectors to the client. It is evident that once that is done - if possible at all - it is impossible to change without reformatting.

MSFN and Axcel216 (MGDX)'s sites are excellent resources indeed - I've known them for more years than I can recount ;=)


--
Czerno

[fzabkar]

ISTR that in the past I was able to download generic firmware updates from PLX Tech for their own bridges ...

Sorry, I was thinking of Prolific, not PLX Tech.