50-PIN SCSI hard disk limited to 4GB, how to fix?

[paul1981]

I have a Seagate ST318417N 3.5" 50-pin SCSI hard disk, and it appears to have been limited to 4.5GB or thereabouts. This drive should be 18GB, and apparently you can issue SCSI commands to do this and set the capacity manually.

What I want to do is restore it to its full capacity of 18GB or whatever it's supposed to be precisely. Is there a tool that can do this?

I have the drive hooked up to the PC and I have Linux and XP available to run software if anyone knows of any. I'd prefer Windows XP because my Linux is out of date and new stuff may not run correctly.

I don't know where to start and I don't know how or what commands to send to the drive.

Cheers for any help you can offer.

[Snoopy1234]

Have you tried adding the PFS3AIO filesystem to HDToolbox and formatting the drive with it in WinUAE?

[thomas]

Ist this an Amiga question?

There might be jumpers on the drive causing a capacity limit.

Which software shows the limit?

[paul1981]

@Snoopy1234
Thanks, but if I was to do that it would detect the wrong size anyway as the SCSI card BIOS utility detects it as 4551MB when selecting option to low-level format drive. I haven't done the format because I don't believe it would make a difference to the size.

@thomas
Well, if anyone has a SCSI controller card and they want to use an old SCSI hard disk in their Amiga, then yes it's an Amiga question.

The limit is shown in all places, including SeaTools for Windows and also the other Seagate software. Linux the same, Windows the same - I'm referring to the partition managers.

https://www.seagate.com/support/disc.../75789521a.pdf

In the manual it talks about using the Mode Select command to program the required capacity. Does anyone know the software I'd need to do that? Nowhere in the manual does it mention jumpers altering the drive capacity.

[mark_k]

You can install the sg3-utils package on Linux. Also see the SCSI Interface Product Manual.

[Snoopy1234]

@paul1981 it might pay to used diskpart in Windows CMD to clean the disk. (Wipe) The HDD may have only been formatted to a 4 gig partition previously which I admit is neat and all the early PC filesystems can handle.

[derSammler]

Originally Posted by paul1981

Thanks, but if I was to do that it would detect the wrong size anyway as the SCSI card BIOS utility detects it as 4551MB when selecting option to low-level format drive.

Use a newer SCSI controller (or updated firmware, if there is any). Early controllers had limits as well, similar to early IDE. 4 GB is actually one of the known limits (among 1 GB for even older controllers). There is no way to get the full capacity using software when the controller simply can not handle it.

[mark_k]

This isn't a host-side software issue, the drive capacity needs to be reset to the default by issuing the appropriate SCSI MODE SELECT command.

[paul1981]

Originally Posted by derSammler

Use a newer SCSI controller (or updated firmware, if there is any). Early controllers had limits as well, similar to early IDE. 4 GB is actually one of the known limits (among 1 GB for even older controllers). There is no way to get the full capacity using software when the controller simply can not handle it.

I didn't consider that, the controller is from 1996-7 iirc. I'll check that out, but I think it's unlikely in this case as it's not ancient ancient.

[paul1981]

Originally Posted by mark_k

This isn't a host-side software issue, the drive capacity needs to be reset to the default by issuing the appropriate SCSI MODE SELECT command.

I hope so, I'm crap with Linux and Windows CLI's though so I've got some reading to do haven't I.

[mark_k]

sdparm should also be able to do what you want. There is a Windows port.

Visual SCSI Explorer is a Windows GUI program which should also be capable of sending the appropriate command. Not sure if that would be any more user-friendly than using sdparm though.

[paul1981]

I finally managed it yesterday with the following under Linux:

sg_format --resize --count=0xffffffff /dev/sdb1

It shows over 19GB now and it formats fine, so all is well. Thanks for your help everyone, and I'll definitely check out that Visual SCSI Explorer, as the way I'm currently doing it is very awkward due to having to boot from a Linux Install CD, as my Linux installation is screwed somehow and won't run sg_format.

It's a good hard disk drive, quite quiet.