Old HDD emulation ?

[bojan]

Gents,

Is there any (low cost) way to emulate old HDD (specifically Conner CP2084), using CF card?
I have an old Toshiba T1850 with failed HDD, and I would like to make it work again..

Search on web resulted in one discussion only (on VOGONS).. with no solution.


Any thoughts?

[AstroViking (Steve)]

Hi Bojan,

Do you need to emulate that specific drive? Or can you get away with some sort of IDE to CF/SD adapter?

I had a quick look around and there are plenty of adapters available that will let you replace an old IDE drive with something a bit newer.

Somewhere in my PC gear collection I have an old external disk enclosure that has a pair of 2.5" drives in it. I can't recall what capacity they are and I never pulled the enclosure apart to see what interface they used.

I can dig it out and see what capacity they are and what interface they use. If they match the old Connor, it's yours for free if it's of use...

Cheers,
V

[bojan]

Hi Steve,
Thank you for the reply and offer. T1850 has 2.5" IDE connector.



According to VOGONS forum, T1850 has old & inflexible BIOS, which accepts only couple of Toshiba HDD's..
Some people tried Anydrive on other models, but were not successful with T1850 apparently...

So it seems I have only 3 options:
- change BIOS
- emulate one of the listed HDD's (CP2048 for example.. on my machine it spins but it seems to be damaged (boot sector? after some time I have message "insert system disk when ready" (FDD also doesn't work, rubber belt turned into black paste..), so it's unusable).
- modify eeprom content on one of sd-cf adaters .. a bit tricky because it needs de-soldering eeprom and putting it back - but doable, provided the method is confirmed to work on that comp.

[AstroViking (Steve)]

Hi Bojan,

I had a look at the laptop's history. My word... I never realised it was 30 years old!

I did some searching around as well and can only agree with what you found with regards to the inflexible BIOS settings and very limited options available to you.

I'll have a look at those drives when I get home this evening. I remember last using it/them in about 2008. So they are probably a lot larger than 80MBytes.

I also have a USB -> IDE adapter you can borrow to test the old drive in a newer machine to see if you can recover it.

Cheers,
V

[dikman (Richard)]

Is it worth persevering with such an old laptop? Unless it has sentimental value....
If you don't need the latest and greatest there are plenty of good deals around on Gumtree, I just picked up two Toshiba Tecra R950's for $150 for the two. In pretty good condition, only thing missing is the hard drive which was no big deal as I've transferred the drive across from the old pentium I was using for running astro software. i5 processor, 8gb ram, 15.6" screen, perfectly adequate for the job.

I also just bought something a bit faster for general use. Acer Swift with a Ryzen 7, 16 gb ram, 1 tb NVMe drive - it's FAST! About a year old, very good condition and less than 1/2 the price for a similarly spec'd unit. Also on Gumtree. Now I'm getting used to Win 11.

[bojan]

Originally Posted by dikman

Is it worth persevering with such an old laptop? ..

Believe it or not, I have a purpose for this kind of machine.
I have a programmer and a >~10 of MC68HC705 OTP processors that I would like to use for various things in the future (yes I know.. I have a number of Arduino boards as well... but this one I used for my own stepper driver for EQ6).
And that programmer doesn't work on a machines faster than ~30MHz because the programming timing is not controlled by ACK signal but rather by the parallel port speed.

This particular laptop I bought on ebay long time ago to have a backup for Mel Bartel's system for my dob.. and it is OK otherwise (FDD also doesn't work but this can be fixed, I only need to replace rubber belt which turned into black paste..)..
Maybe I am sentimental, a bit too much

[bojan]

Now I have an idea.. perhaps FDD emulator with Arduino nano can be used as input device?

[mura_gadi (Steve)]

Not sure if this would work, but can you do a low level format and just set the track and sectors to the older HDD settings?

You'd need an older drive to start with, but, at least the BIOS would recognise the drive.

[bojan]

Originally Posted by mura_gadi

Not sure if this would work, but can you do a low level format and just set the track and sectors to the older HDD settings? ...

Hmm.. How can I do this? Original HDD setting are on the link here.

This guy apparently altered the content of eeprom on the SD_CF adapter for his T4400C, see here, 3rd post from bottom up. It seems he de-soldered the eeprom, reprogrammed it and soldered it back.
I ordered SD-CF adapter from Alibaba, it would be interesting to see if that's feasible to do in my case..

[AstroViking (Steve)]

Sadly, you can't do that.

Very, very old drives (MFM and RLL interfaces) needed to have their specifications set in the computer's BIOS or on the controller card. IDE drives moved the 'smarts' from the controller card to the drive.

The number of cylinders, heads and sectors per track are presented to the computer via the IDE controller on the drive. The actual number of cylinders / heads / sectors within the drive could be wildly different because the controller carried out address translation on-the-fly as the drive was accessed.

Nice idea, though!

Originally Posted by mura_gadi

Not sure if this would work, but can you do a low level format and just set the track and sectors to the older HDD settings?

You'd need an older drive to start with, but, at least the BIOS would recognise the drive.

[AstroViking (Steve)]

Hi Bojan,

No luck with the drive enclosure I mentioned. The two drives inside are 2.5", 80G each. (Old school Parallel ATA / IDE.)

If a Lacie 'Little Big Drive' with 2 * 80G drives configured in hardware as a RAID0 (160G) disk is of use to you, it's all yours. I suspect it needs an external power supply as hooking it up by the USB port didn't do anything. It has FireWire 400 and 800 (remember that?) ports as well as a USB and external power.

Cheers,
V

[bojan]

Steve,
Thank you for the offer, I really appreciate it but first I have to sort out FDD (belt) as the first and possibly only entrance port into that T1850.
On this website I found Anydrive.zip utility that could be helpful for some other old machines (but apparently not for T1850, according to some reports.. ).

[bojan]

It seems there is FDD emulators out there...
Like this one.

I wonder if this (or similar) can be used for T1850..

[AstroViking (Steve)]

No worries at all!

I'm going to follow how your work goes, as I'm curious about retro-tech like this.

I cut my teeth on computers back in the 80s, and the IBM PC world from the XT onwards, so this is a trip down memory lane. Anyone else remember 'debug' and "g=c800:5" ??

Cheers,
V

[bojan]

Yes.. my first comp was Clive Sinclair's ZX80.. then in mid-late '70s I built Apple II from scratch (well not entirely, we get hold of films for motherboard), the rest was soldering TTL logic chips in place.. it worked OK, then I learned to program in assembler (for 6502).

It was great fun :-)

[mura_gadi (Steve)]

I was very old school as well, 286+ days for work, but we owned a Sinclair and a wombat/tiger the apple I and II clones for home use.

Try a PC recycler, they would receive some very old PC's and may have something in stock that would work.