its probably failing only when its error count exceeds a maximum value of accumulated errors. a lot of old drives would have the errors written on a tag on the outside of the drive and were designed to work with those errors there.

keenmaster486 wrote:

I set the interleave to 2 and reformatted - also I think I have figured out that it is an 818 cylinder drive because it chokes while formatting if the cylinders are set higher than that. Still can't verify the format though.

I will be posting pictures later.

It is strange to me, though, that the formatting utility will get very far at all formatting with different C/H/S settings; you would think it would just exit with an error if it was not correct. How could it format for 5 heads when there are only 4, for example?

This makes me suspect more and more that it is a ST-251 (MFM 42.8MB, 820 trks, 6 heads) or similar drive, being RLL-"overclocked".

Edit:
The old Shugart interfaced drives are typically verified *after* full formatting.
The reason of the failure might be as simple as the defects count exceeding which the ROM formatter can store (not much more than a handful).
There seems to be a big bad range around cylinder 300.

You need an utility that can build a bad sectors list with more than, say, 20 entries.
Back then I used SpeedStor for this, because Ontrack (which seems to be popular here for reasons I fail to understand) is just buggy crap that promises many things it fails to do. Even trying it out is a waste of time.

I believe old SpinRite could also do it

Update!

(retardware, I will try what you have suggested with SpeedStor. It would be great if I could get the original drive to work.)

I have purchased a new drive for the unit. It is a Toshiba MK56FB, 105 MB drive. See the C/H/S settings for it here: https://support.toshiba.com/support/viewConte … ontentId=107634
It apparently can do MFM or RLL.

So far, the controller does not like it. I set the jumper settings to switch "1" on, all the rest off, as per the manual here: ftp://bitsavers.informatik.uni-stuttgart.de/p … anual_Feb89.pdf
But I am really not sure whether I did it right. Plus there are quite a few more jumpers on the drive that I am not sure about. For example, what if there is one to switch between MFM/RLL mode? The manual says nothing about that.

I tried setting the C/H/S settings in the BIOS, but it said "C: drive failure".

So, am I out of luck? Is this drive completely shot? Or am I doing something wrong?

(btw, it is ridiculously large. 5.25-inch drive as opposed to the old one which is a 3.5 inch - and it is twice as high.)

wow cool 😀
5" FH, that got rare nowadays.

There are no switches for selecting MFM/RLL.
Did you put in the seven jumpers which connect the terminators? Without terminator there will be only errors.

If this does not help, then you might have to enable ST-506 (drive defaults to ST-412, which is way more efficient), as not all controllers support ST-412.

Don't worry if you don't succeed immediately. These old drives were not always that simple to configure, especially if the bios did not support user defined types.

I got lucky on eBay, the seller even parked the heads before sending!

My board is the F5A-A4 variant - and has DIP switches for the settings, with some kind of chip in a socket where the "terminator" is marked on the diagram in the manual.

I don't think it has jumpers for the terminator!

Could you please post some photos of the drive?
For some reasons:
- To let us see a 1980s Toshiba 5" FH drive
- To let us see too which versions are built in and interpret the manual correctly together, with many eyes
- Nerd porn always is good 😀

Toshiba drives were no crude things like Seagate.
I suppose they had that "chip", actually a DIL resistor network in a socket like others too, but unlike with Seagate it was not intended to be removed for deactivating the termination, instead it was to be enabled by adding the respective jumpers.

Edit:
According to the manual, the drive already has autopark. You can hear that.
There are programs to park, but they are not really needed except for drives older than your [probable] ST-251. Afaik autopark was introduced with that model, and Seagate was not the first one to introduce it iirc.

retardware wrote:

According to the manual, the drive already has autopark. You can hear that.
There are programs to park, but they are not really needed except for drives older than your [probable] ST-251. Afaik autopark was introduced with that model, and Seagate was not the first one to introduce it iirc.

Hmm it's unlikely to be a ST-251 if it's a 3.5inch MFM HDD... The ST-251 was a 5¼ half height hard drive, and yes it had autoparking upon power down.

Vynix wrote:

retardware wrote:

According to the manual, the drive already has autopark. You can hear that.
There are programs to park, but they are not really needed except for drives older than your [probable] ST-251. Afaik autopark was introduced with that model, and Seagate was not the first one to introduce it iirc.

Hmm it's unlikely to be a ST-251 if it's a 3.5inch MFM HDD... The ST-251 was a 5¼ half height hard drive, and yes it had autoparking upon power down.

The only photo we have is in the first post. To me the HDD looks like 5.25" HH. But to me it looks not like Seagate, instead another manufacturer, so I suppose a ST-251 compatible thing.

The OP would make things easier for people willing to assist if he would be a bit more generous with showing photos.

Hey guys, sorry for not posting more pictures yet; I've just been pretty busy the last few days! I'll get them posted this evening.

The original drive is a 3.5 inch drive in a 5.25 inch caddy.

Here's a quick pic of the new drive, which I happened to have with me (I'm not at home until the evening):

FINALLY getting around to working further on this 286.

Pics of the drive:

Right now the issue is that the controller is not even detecting it.

I also got a Tseng ET3000AX VGA card for it because the Oak sucks (will test soon):

Any tips on this hard drive? I cannot seem to get the controller to detect it. It says "controller reset failed - no drives installed" or something like that. The drive spins up, though. I have the jumpers set correctly as far as I know, but there may certainly be something wrong there.

Finally got the huge drive working!!

I had to switch it to "radial" mode from "daisy chained" mode, whatever that's supposed to mean. After that, it worked perfectly. Low level formatted it using the controller card's utility, and dutifully entered the defect list printed on the label.

Got MS-DOS 5.0 installed on it, and after a network packet driver and MTCP, some FTP action ensued - I was able to log into it from FileZilla on my IBM Thinkpad A20m and load up some software, for some awesome vintage-to-vintage action going on.

This machine is very loud, very slow, and very MS-DOS.

I'm psyched.

So far I've only tested MTCP plus some games (Commander Keen, of course. Hocus Pocus and Wolfenstein 3D work, but are both too slow to be enjoyable. Skyroads works fine, however.). Tomorrow I will test Arachne on it to see if I can browse the Web usably.

One more thing: I had to switch out the Tseng ET3000AX with the Oak card I had in it originally - the Tseng started having issues (monitor was detected as monochrome spontaneously and inexplicably!). Plus the Oak seems to actually be faster, and the weird color artifacts that were there before have ceased, probably because I have a different monitor now.

I'm taking suggestions for good games to play on this computer!

Some pictures! (also edited into original post)