Hi there! 🙂
Well, it depends.. Short answer: No.
Long answer: Yes, but it's expensive. ST412/ST506 are more like "analogue" connections.
The actual MFM/RLL HDD controller you have in PCs is a WD1003 compatible. IDE/ESDI speak same WD1003 language.
So in order make the old MFM/RLL controller work, you would need a complicated, powerful HDD emulator that behaves like a magnetic disk spinning at 3600 RPM in real-time.
Which is very computing-intensiv.
For industrial use, such HDD emulators do exist, but they're very expensive.

Jo22 wrote on 2023-06-23, 13:50:

ST412/ST506 are more like "analogue" connections.

Wow that's neat technology, now I appreciate my hard drive even more and certainly won't want to use it for just playing games. Hunting for an ISA IDE card will be my goal now so I can honourably retire the old hard drive. I really didn't know what I had in my hands until now.

Although I wonder whether a modern Raspberry Pi would be able to do it. It should have enough bandwidth. The "only" thing is missing the software.

EDIT: It seems that nope, FPGA is needed for that. Someone has already wrote an open source ST506 emulator for DE-10 Nano board. Analogue still beats software, in some sense.

Which 386 computer/motherboard exactly? Does it have a common BIOS? Chances are that the MFM controller+HDD were transferred from an older setup and that you can replace them by an IDE controller+HDD/CF.

konc wrote on 2023-06-23, 14:20:

Which 386 computer/motherboard exactly?

It's HP Vectra QS/16S with ST-506 F-F (45945-60013) controller. I was 6 years old when it was manufactured so naturally I am a bit lost here!

konc wrote on 2023-06-23, 14:20:

Does it have a common BIOS? Chances are that the MFM controller+HDD were transferred from an older setup and that you can replace them by an IDE controller+HDD/CF.

The bios seems to be proprietary. Everything in it seems to be original parts and excellent condition. Sorry I don't know what MFM is, I need to do some research.

EDIT: MFM seems to be the analogue hard disk type, makes sense.

So can I just get any ISA IDE card and call it a day or should I consider something I don't know of?

Also thank you for you all who have helped me so far!

EDIT again: The older bioses, do they support any kind of IDE controllers? There are ISA CF controllers, would these work for me? I am concerned of the proprietary bios that it might not support anything beside the original manufacturer parts.

Hi again, this old thread might be helpful, too.
At the end, there's a link to a backup of the setup disk.
HP Vectra QS/16S

Good luck.🙂🤞

Edit: Yes, most (if not all) PC/AT compatible PCs do support IDE.
That's because IDE is like a superset of MRM/RLL controllers (it adds HDD identification features etc).
But the core functionality is same, no need to worry.

Now to the "problems": The old IDE standard was in use up until 1994, roughly. After this, subtle changes appeared (ATA-2 specification).

So depending on how old the PC BIOS, problems can happen.
For example, my Schneider Tower AT 286 (also shipped w/ MFM HDD originally) was hanging when I tried to use an ISA IDE controller card and an CF card via adapter.

However, it wasn't an electronic problem.
If I changed the HDD type to "none", it booted from floppy.

My solution was to leave it that way and use XT IDE Universal BIOS instead.
It's much newer than the ancient MFM/RLL HDD routines in the 1988 BIOS.
I had no problems since.

Edit: Typo fixed.

Jo22 wrote on 2023-06-23, 14:54:

Good luck.🙂🤞

Thanks I will need it! Actually I read that thread before buying mine and the fact there was disk images available convinced me that I can do this 😀

Yes you can replace what you have with an IDE controller+HDD. But
1. That's a very early 386, you need a setup disk to configure the BIOS. There is one in archive.org uploaded by vogons member @Burrito78 in this post Re: HP Vectra QS/16S
2. Not all setup disks work with every PC, probably something with BIOS versions. If this one doesn't work for you you'll need to find one that does.
3. By default only fixed HDD types can be selected, in order to specify a custom type run setup.exe manually with the /S parameter

Edit: Ah I see you found the thread with the setup disk as I was writing this, good

It seems the bios does not support anything else beside setting the hard disk size, so I think it will use some kind of hard-coded values for everything else. That being said, this very same model was produced with IDE controller as well (IDE M-F (D2384-63031)), mine is D1474A and D1474B would be with the previously mentioned IDE controller. So, if I can find the said controller I could upgrade to B standard. Or, if somehow the IDE CF could pretend to be compatible with my bios. Or maybe I should just keep using my computer as is and not worry about eradicating my hard drive, I have no idea how rare these are, but I'd like to keep everything original and working.

And I thought I had taken everything in account, but no, this hard drive threw me a curve ball. I need to meditate a bit on this.

konc wrote on 2023-06-23, 15:03:

Yes you can replace what you have with an IDE controller+HDD. But
1. That's a very early 386, you need a setup disk to configure the BIOS. There is one in archive.org uploaded by vogons member @Burrito78 in this post Re: HP Vectra QS/16S

I am worried because the bios only lets me to select the size, not all the parameters of the disk! I am only accustomed that software does this for me, but I understand why these early hard drives had such option. No idea whether the IDE CF controller supports this. Thank you for your advice, I am a bit wiser now!

EDIT:

konc wrote on 2023-06-23, 15:03:

3. By default only fixed HDD types can be selected, in order to specify a custom type run setup.exe manually with the /S parameter

This fixed my problem, all clear now!

If the BIOS doesn't support the necessary HDD settings, you could trying using an XTIDE BIOS extension to enable support.

I do this with a few 286 computers I have that don't support custom HDD settings. I use the Lo-tech ROM cards with an XTIDE BIOS.

Here's a "hack" from the old days:

You can always use parameters that are within the specifications of your HDD.

So if the HDD has 500 cylinders, 15 heads, 63 sectors you can choose an entry with, say, 300 heads, 12 heads, 63 sectors.

If the HDD is made in the 90s or later, it's even simpler, maybe:
Then the HDD parameters of higher capacity HDDs had become purely fictional, already.
Just make sure you don't exceed total drive capacity (in MB).
The term is "sector translation", I believe.

By 1988/1989 onwards, the IDE electronics did start to use a translation for the drive geometry.
Ie, the physical and logical parameters are nolonger the same.
Models with with 40 or 80 or 120 MB started to use that.

By the mid-90s, 486 PCs started to have BIOS support for LARGE (E-CHS) and LBA.
This allowed HDDs to be fully supported up to 8GB and beyond.

Shponglefan wrote on 2023-06-23, 15:23:

If the BIOS doesn't support the necessary HDD settings, you could trying using an XTIDE BIOS extension to enable support.

I will read about his option more, sounds promising. A great band by the way.

Jo22 wrote on 2023-06-23, 15:41:

By the mid-90s, 486 PCs started to have BIOS support for LARGE (E-CHS) and LBA.

I remember LBA from my first self-assembled computers, I had no idea what it meant but I guess everything was in LBA mode already back then. Invaluable information again, thanks!

doublebuffer wrote on 2023-06-23, 16:55:

I had no idea what it meant but I guess everything was in LBA mode already back then

Generally the opposite, most contemporary operating systems (= MS-DOS 6.22 and earlier, and Win16 + 9x without "32 bit disk access") and bootloaders only support "traditional" int13 disk access, which is CHS only 😀 🙁 (only later did the real-LBA "int13x extensions" become available AND implemented in software)

LBA in that context (the BIOS setup, as "LBA mode on/off" or "Normal/Large/LBA") means to convert traditional int13 CHS access into LBA requests, which is generally a good thing for compatibility since the calculation is standardized, unlike the various CHS translation formulas all called "Large" - unless of course you have a non-LBA disk 😀

Ryccardo wrote on 2023-06-25, 14:15:

doublebuffer wrote on 2023-06-23, 16:55:

I had no idea what it meant but I guess everything was in LBA mode already back then

LBA in that context (the BIOS setup, as "LBA mode on/off" or "Normal/Large/LBA") means to convert traditional int13 CHS access into LBA requests

I think my first self-built computer always booted up the disk in LBA mode, it was win95, I had no idea whether I should enable it in bios or not. I had no documentation or internet or anything, everything was trial and error. Well, live and learn.

I stumbled across this discussion on a fork of FlashFloppy that interfaces a Gotek (the original 72MHz Cortex-M4) to ST506 via an adapter, which shows that it's possible with inexpensive hardware. I presume it operates in the same way by serving up disk images stored on a FAT32-formatted USB flash drive. The discussion and development seems to have stopped though, just as the newer Gotek with 288MHz M4 became available.

jtchip wrote on 2023-06-29, 01:04:

I stumbled across this discussion on a fork of FlashFloppy that interfaces a Gotek (the original 72MHz Cortex-M4)

Interesting, I do have Gotek but I'm unsure what MC it has, it's something like four years old so I have to explore that possibility. Thanks for the heads up!