if it's anything like the keyboard locks you can just disconnect the 2 pin cable going to it

The XT bios does not support disk change detection (and 360K PC drives use pin 34 in a different way than later drives). The consequence of no disk change detection is that those bioses also have no code to "clear" the "disk has changed since last seek" state. On AT-compatible drives (360K drives were never upgraded, though), a disk change is latched and available on pin 34 (when the drive is selected), and it is used by the BIOS to return "error 6" to tell DOS to flush the cache. To tell the drive that it may de-assert pin 34, a seek needs to be issued. If no disk is inserted, most drives immediately re-assert pin 34. The seeks to clear the change line (stepping between track 0 and 1) are the cause of the rattling sound associated with the "drive not ready" condition. Don't expect to hear that sound from an XT BIOS. It is completely normal for an XT trying to boot from a drive that is already track 0 to just turn on the drive LED for about a second, without any audible noises.
Early XT BIOSes also only were meant for 360K drives, so they don't do the patented(!) IBM magic bootup seek sequence, that is meant to tell 80-track and 40-track drives apart. So also don't expect the well-known daaah-daah-doot sound from an XT POST, if it is a pre-1987 BIOS.

Cool dumpsters in your neighborhood 😀

mkarcher wrote on 2020-06-10, 00:21:

Don't expect to hear that sound from an XT BIOS. It is completely normal for an XT trying to boot from a drive that is already track 0 to just turn on the drive LED for about a second, without any audible noises.
Early XT BIOSes also only were meant for 360K drives, so they don't do the patented(!) IBM magic bootup seek sequence, that is meant to tell 80-track and 40-track drives apart. So also don't expect the well-known daaah-daah-doot sound from an XT POST, if it is a pre-1987 BIOS.

Okay, then I suspect it did try to boot from the 5.25" drive, as with a random 5.25" disk inserted it did briefly flash the LED without any audible noise. It looks to be a 1986 BIOS, which also suggests this is likely a 360K 5.25" drive I assume? I think the floppy drives are attached to an add-on card.

Swiego wrote on 2020-06-10, 00:23:

Cool dumpsters in your neighborhood 😀

This was definitely a rare find. Even when we had a decent accessible electronics drop-off spot it was largely P3/P4/later stuff, and a copius amount of random LCD panels and broken TVs.

Edit: Dumpster is probably an exaggeration of this find in a way. "Skid sitting in an empty lot with an 'Electronics DropOff' sign stuck next to it' find is the more accurate description.

You can look at the model number of the 5.25" floppy drive. Likely it is 360k. It will illuminate on boot for a second to see if there's a disk inserted, then it will go to the hard drive to boot. It won't try to seek or make noise if there isn't a disk.

LHN91 wrote on 2020-06-10, 00:29:

It looks to be a 1986 BIOS, which also suggests this is likely a 360K 5.25" drive I assume? I think the floppy drives are attached to an add-on card.

No standard XT BIOS I know of supports high-density drives (1.2MB or 1.44MB), and neither do floppy controllers that were shipped with XTs. If that Turbo XT had a 1.2MB or 1.44MB drive in it, it would need special DOS drivers to make use of it. Furthermore, 1.2MB drives can not even read 360KB floppies without special BIOS/driver support. So for your XT, I am quite confident that it only contains DD drives, so two 360K drives, or a 360K 5.25" and a 720K 3.5" drive. Many BIOSes that have no specific 720K support still work with those drives, because they just behave like a 360K drive, but having more tracks. If the BIOS does not bounds-check the track number, it will automatically support 720K DD drives along with 360K drives.

The XT board you show seems to be from a time before we had highly integrated chipsets. The consequence of that is that the standard components (RAM, IRQ controller, DMA controller, timer, I/O decode, bus drivers, clock generator, keyboard interface) occupy that much board space that nothing is left for I/O like floppy controller, parallel or serial ports, or even a hard drive controller. So it is very likely that the floppy drives are attached to an add-on card. The data rate of DD floppies is 250 kBit/s, and most floppy controllers need a 8MHz crystal to support this data rate. If it were a HD-compatible floppy controller (which would definitely not be stock XT equipment), the card would most like have a 16MHz crystal for the HD data rate of 500kBit/s instead of the 8MHz crystal, as well as a *second* crystal of 9.6MHz for the data rate of 300kBit/s you need for 360K disks in 1.2MB drives (those drives spin faster). So checking the crystals on the floppy controller card is an easy way to check for HD support.

Great find ! Yeah the keylock is for keyboard and probably at one time the two disks would lite, red for locked and other green for unlocked. Have a case that does that but does not use floppy symbol but a padlock symbol. Most likely the HD is dead, those old MFM/RLL just don't last 35 years....
Without seeing the actual floppy drive and controller would assume it is a 360k drive but there were many (like me) that swapped in a newer Floppy controller (with it's own bios) that supported HD floppy drives on computers that did not.
Repeat: great find !

Nice pickup. I fitted a high density fdd controller and XT-IDE card to my XT Turbo system. Makes file transfers and storage so much easier.

Horun wrote on 2020-06-10, 00:50:

Most likely the HD is dead, those old MFM/RLL just don't last 35 years....

Don't tell that to the ST-238R in my Turbo XT, please! It seems to have needed a little "warm-up" after more than 20 years in the attic, but it works fine again. There are ways to "revive" dead drives by oiling the stepper motor and banging it from the side to unstick the heads. Thankfully, I didn't need either, but they might be worth a try on dead drives. And just one advice from experience: If you get drives from the late 80s running again, or you are looking through a late 80s floppy collection: Do check for boot sector viruses!

My Turbo XT has an extremely similar case, a 360K and a 720K drive, but a different mainboard. I got it with a Genoa Super-EGA card in it, which is also a nice thing to have.

Caluser2000 wrote on 2020-06-10, 00:53:

Nice pickup. I fitted a high density fdd controller and XT-IDE card to my XT Turbo system. Makes file transfers and storage so much easier.

Using the XT-IDE card to get more reliable storage than a 35 year old MFM or RLL drive is a good idea for sure. I solved the file transfer problem a different way though: I added an ethernet card, and I use etherdfs to access files via network. The server needs to be a Linux machine - in my case it is the SOHO internet router.

mkarcher wrote on 2020-06-10, 01:04:

Caluser2000 wrote on 2020-06-10, 00:53:

Nice pickup. I fitted a high density fdd controller and XT-IDE card to my XT Turbo system. Makes file transfers and storage so much easier.

Using the XT-IDE card to get more reliable storage than a 35 year old MFM or RLL drive is a good idea for sure. I solved the file transfer problem a different way though: I added an ethernet card, and I use etherdfs to access files via network. The server needs to be a Linux machine - in my case it is the SOHO internet router.

Good solution if the MFM/RLL hdd is working fine. The one on mine wasn't. No matter what I tried it wouldn't function so opted for the most sensible and fuss free solution. I had the HD FDD from another XT I stripped a few decades ago so it made perfect sense to make use of it 😉

mkarcher wrote on 2020-06-10, 01:00:

Horun wrote on 2020-06-10, 00:50:

Most likely the HD is dead, those old MFM/RLL just don't last 35 years....

Don't tell that to the ST-238R in my Turbo XT, please! It seems to have needed a little "warm-up" after more than 20 years in the attic, but it works fine again. There are ways to "revive" dead drives by oiling the stepper motor and banging it from the side to unstick the heads. Thankfully, I didn't need either, but they might be worth a try on dead drives. And just one advice from experience: If you get drives from the late 80s running again, or you are looking through a late 80s floppy collection: Do check for boot sector viruses!

My Turbo XT has an extremely similar case, a 360K and a 720K drive, but a different mainboard. I got it with a Genoa Super-EGA card in it, which is also a nice thing to have.

The ST-238R lives!

For context:

I pulled out the combo Floppy/Multi-IO card to grab a photo. It was in there really firmly, I really had to work it (slowly) to get it out of there. Looks like a 1985 copyright date. Not much else in terms of identifying marks, but it's got dip switches for some kind of configuration.

I also noticed that the wonderful Varta I thought hadn't leaked quite yet actually had. Looks like I've got some work to do on this, but I'm glad I caught it when it hadn't hit the motherboard yet.

So I left out the floppy/multi IO card, and also disconnected the lock switch from the motherboard, and then just for the heck of it tried to start it again. Lo and behold, the drive spun up, seeked for a bit, complained about not having been parked, and then booted to what I assume is a corporate quick-launch system:

Also, a better photo of more of the motherboard, just in case someone recognizes it:

I'm a bit concerned because the launch menu seemed to have a clock that was keeping time. I don't see any other batteries on board so far except the one on the floppy, but I'm a bit worried there's one hidden somewhere.

That Vatra battery will be keeping time. The clock timer will be on the same ISA card. Swap out the battery for a coin cell holder and you are good to go. Congrats on getting the hdd running.

Interestingly, the floppy controller card has a 16MHz crystal, yet the Zilog controller chip is only specified up to 8MHz, so the crystal frequency is probably divided by two. This could be an attempt to get a better 50% duty cycle than from a typical 8MHz oscillator. This multi-I/O card with on-board battery backed clock is very typical XT material (as the AT has the battery backed clock on the main baord), so I am extremely confident this is a DD-only only floppy controller. The "Varta" battery is actually made by GP, not by Varta.

XT computers have the clock either on a separate ISA card or on the multi-I/O card, so you don't need to search the mainboard, the hard drive controller or the graphics card for a second battery, there will be none.

Your board seems to be a clone of the DTK PIM Turbo mainboard: https://gizmofoundry.com/project-8088-dtk-pim … 8-2-components/

Caluser2000 wrote on 2020-06-10, 01:34:

That Vatra battery will be keeping time. The clock timer will be on the same ISA card. Swap out the battery for a coin cell holder and you are good to go. Congrats on getting the hdd running.

I took the card out of the machine - It was actually counting time on that launch screen with the floppy card not in the machine, which is what worried me.

Also, upon successive boots, the hard drive lives-ish. I was able to boot it a couple more times as I tried a couple PS/2 keyboards through an adapter (no luck, unfortunately), enough to know that an install of DOS 3.2 or 3.3 is on the drive.

After that first few successful boots, however, now it spins up, but seems to have an issue seeking - it tries 2 or 3 times and then fails to a Disk Boot Failure. I'll still play around with it to see if I can coax it into living again.

You need a real XT keyboard (or an AT that has a switch for xt/at), there are no real good adapters for XT. I do not see a cpu on the main board, was it hidden in your pictures ?

Horun wrote on 2020-06-10, 02:00:

You need a real XT keyboard (or an AT that has a switch for xt/at), there are no real good adapters for XT. I do not see a cpu on the main board, was it hidden in your pictures ?

The DTK PIM Turbo that was noted above looks to be what this board was a clone of - the 8088-2 is up on the top right above the HDD controller. It's even a Fujitsu part number.

EDIT: Someone noted in the Dumpster Find thread that some later XT BIOS's had support for AT keyboards - figured it was worth a try anyways.

Thanks ! I could not see it in this post picture: download/file.php?id=85488&mode=view