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Mike Chambers
November 28th, 2013, 11:12 AM
Okay, this problem is stranger than the topic makes it sound. I have this 286 that will just not boot from an IDE hard drive, even though I can see hard drive after booting from floppy. I can fdisk and install DOS seemingly without error. I can see the directory structures on the drive, but running any programs from it just causes it to hang. Attempting to boot DOS from the hard drive doesn't print any error messages, it just hangs. It's not a hard lockup, I can still toggle numlock, etc. I've tried:

- Multiple hard drives (all known good in other machines)
- Multiple drive controllers, including ones with their own disk BIOS that override the 286 BIOS disk functions... except the XT-IDE card, that's the only one that works but I need that card in my 5150 and only have one.
- Multiple DOS versions, both 5.0 and 6.22.
- Playing around with different geometry settings in the BIOS.

Has anybody ever seen something like this before? Apparently it reads and writes to the disk since I can install DOS from floppy and then even browse the directory structures, but it simply won't execute code or boot without hanging! I can do anything and run any program from floppies without issues.

giobbi
November 28th, 2013, 11:47 AM
OK I admit it's just a shot in the dark and you probably already thought at it, but... did you try to delete autoexec.bat and config.sys?
In other words couldn't be some driver or some "innocent" tsr or other program that's hanging the system?

Mike Chambers
November 28th, 2013, 11:50 AM
It doesn't even get to the point of loading them. It never even gets to "Starting MS-DOS..." unfortunately. It's got to be something on a lower level than that, considering how it won't even run programs from a hard drive after booting from a floppy. I've even re-partitioned and re-formatted multiple hard disks on multiple drive controllers several times. However, I've checked the contents of a text file on the hard drive and it appeared to be uncorrupted so I have no idea what's going on with this thing!

I'm going to try a couple diag programs like CheckIt and PC Pro from floppy to see if they come up with anything.

EDIT: All tests I run pass. Memory, disk, system board (IRQ, DMA, etc), everything!

Chuck(G)
November 28th, 2013, 12:33 PM
Try an FDISK /MBR. A screwed up master boot record can really create a mess.

How big is the hard drive and are you running an DDO on it?

Mike Chambers
November 28th, 2013, 12:47 PM
I've already run fdisk /mbr on each hard drive I've tested, and it never helped. The hard drives I tried range from 200 MB to 2 GB. I'm not using any DDO software, but I'm considering installing EZ-Drive and seeing if it will get me past this problem.

Chuck(G)
November 28th, 2013, 01:52 PM
If the boot process is hanging, either there's something wrong with the geometry or with the MBR. What happens if you HL (FORMAT) format your boot partition without putting a system on it? i.e., just do a FORMAT C:. Do you get the "Operating System not Found" (or something like it) message? The code that generates that message is in the MBR.

SomeGuy
November 28th, 2013, 02:24 PM
It sort of sounds like an odd DMA or IRQ issue. What other devices are in this computer? Can you disable or remove them?

Although it is not directly applicable to IDE drives, you might try throwing Spinrite at it. It does a fairly comprehensive test of the environment and might detect something.

Mike Chambers
November 28th, 2013, 03:21 PM
If the boot process is hanging, either there's something wrong with the geometry or with the MBR. What happens if you HL (FORMAT) format your boot partition without putting a system on it? i.e., just do a FORMAT C:. Do you get the "Operating System not Found" (or something like it) message? The code that generates that message is in the MBR.

Geometry matches that of the label on the drive, except fewer cylinders since the 286 BIOS only support 1024. So, that is fine. It doesn't show "operating system not found", I only get "Non-System disk or disk error, replace and press any key when ready" as it tries the floppy. The computer DOES apparently read the MBR because the HDD light quickly flashes once after the floppy test. Craziest thing about this is that if I boot from the floppy and use a program to actually examine the MBR contents, they are fine. FDISK also correctly reads the partition info.

Weirdest thing I've seen in quite a while.

Mike Chambers
November 28th, 2013, 03:22 PM
It sort of sounds like an odd DMA or IRQ issue. What other devices are in this computer? Can you disable or remove them?

Although it is not directly applicable to IDE drives, you might try throwing Spinrite at it. It does a fairly comprehensive test of the environment and might detect something.

Spinrite found nothing strange, and the only cards in it are the disk controller and a VGA card. I suppose it can't hurt to try a different VGA card, but I doubt anything will change.

Mike Chambers
November 28th, 2013, 03:27 PM
Oh, and one of my disk controllers had an empty ROM socket so I flash an EEPROM of the Universal XT-IDE BIOS (ide_at.bin) and installed it, set the jumpers for segment CC00h. It doesn't ever run the option ROM during POST, even though I wrote a program to checksum the ROM at that location and ran it from a floppy and it passes. The entire ROM is accessible and matches the original file! What in the world is going on??

If I boot the floppy and then manually jump CS:IP to CC00:0003, the ROM code executes!

AnyoneYoubet
November 28th, 2013, 03:30 PM
there was a program you had to run for it to be boot-able in bios.
check there, also check the pins at the plug for the drive for master setting..
on more thing , is the drive even small enough for the 80286, I think it was under 1 gig drive, not sure on that.

Mike Chambers
November 28th, 2013, 03:33 PM
there was a program you had to run for it to be boot-able in bios.
check there, also check the pins at the plug for the drive for master setting..
on more thing , is the drive even small enough for the 80286, I think it was under 1 gig drive, not sure on that.

The drive size actually isn't an issue, as the same thing happens with even much smaller drives. Also, simply lowering the cylinder count in BIOS to what the 286 can handle will make a too-large drive work, only showing less space than it really contains.

Cager
November 28th, 2013, 03:59 PM
You say that the XT-IDE drive controller card is the only one that works - you therefore have the solution to your problem - ie what is the "difference" that the XT-IDE card brings with it?

Mike Chambers
November 28th, 2013, 04:00 PM
Alright, now I've installed EZ-Drive on it... but it still doesn't work. It loads the EZ-BIOS overlay from the drive, but it hangs trying to detect the geometry! It shows this, and the cursor just sits flashing on "Cylinders" indefinitely. What's wrong with this thing? (This is with any disk controller I try it on, I have 4)

http://rubbermallet.org/286.JPG

Mike Chambers
November 28th, 2013, 04:00 PM
You say that the XT-IDE drive controller card is the only one that works - you therefore have the solution to your problem - ie what is the "difference" that the XT-IDE card brings with it?

Well, it's not a solution because I need that card in my 5150 and this 286 SHOULD be booting on it's own without it. The only difference is that it's an 8-bit ISA card, and I may be mistaken but I think it doesn't use IRQ or DMA.

Cager
November 28th, 2013, 04:15 PM
Apologies for any confusion - the suggested solution was not to use the XT-IDE card, just to determine why it worked - which should then point you towards the reason that the other controllers don't.

If, as you say, it doesn't use IRQ or DMA & that is the only difference, then you may have IRQ or DMA conflicts with the other controllers.

Mike Chambers
November 28th, 2013, 04:20 PM
My fault - I realized what you meant after I read it again. That would make sense with the conflicts, but I'm not sure what it could be conflicting with. I only have a VGA card and the disk controller installed. :(

Mike Chambers
November 28th, 2013, 04:23 PM
So, I dug up another old drive - this time a 341 MB Seagate. This one DOES work!! :)

I would still love to know what the hell happening with all the other drives, even a couple that are known good in other machines and are certainly small and old enough to where it shouldn't cause any issues in a 286. Also, I'm a little bit concerned about how long this Seagate will last. The motor sounds like it really is working extra hard to get up to full speed, although once it does it sounds fine... but it might be getting close to worn out.

fatwizard
November 28th, 2013, 08:24 PM
I'm curious Mike, do you have an MFM card and drive to try, or perhaps scsi? I don't know what's going on with it either, but it's beginning to smell like a motherboard issue of some kind and that might narrow things down.

leeb
November 28th, 2013, 09:30 PM
Couple of things...
Boot the unbootable drive from floppy again, and attempt to view a text file on it. Perhaps it will confirm that the data is being read correctly... or not.

Speedstor is probably the better choice for figuring the WRITTEN configuration of the drive (but not necessarily the same as the 'designated' one)...

You may have to lose the data IOT use the drive. :(

AnyoneYoubet
November 29th, 2013, 02:11 AM
found this

http://www.pcxt-micro.com/harddrive.html

good luck

leeb, your profile photo shows my first computer. Mine was a compact portable, and I had to use the program in dos to prepare the hard drive to boot from. I don't remember the name of the program.

Stone
November 29th, 2013, 04:32 AM
I've already run fdisk /mbr on each hard drive I've tested, and it never helped. The hard drives I tried range from 200 MB to 2 GB. I'm not using any DDO software, but I'm considering installing EZ-Drive and seeing if it will get me past this problem.Forget about any drive(s) over 504MiB/528 MB. There aren't any 286 BIOSes that can correctly deal with a drive larger than that without some outside help such as a DDO. Stick to drives below that, at least for now.

Dca2
November 29th, 2013, 10:15 AM
Just my two cents:

I've encountered similar symptoms on an old 386 mobo in poor condition -- it could boot from FD but not from HD (even with correct CHS in CMOS), it could list HD contents if booted from FD, but can not correctly read any file on HD... The problem ended up with a micro crack found on a thin PCB track leading to a data pin of 16-bit extension part of all ISA slots. This was hard to believe because my 16-bit ISA VGA card was working properly. The fact could be that my VGA card (T8900C) was smart enough to detect the problem and switched itself to 8-bit mode silently. But my super I/O card was not as smart. FD was ok because it only uses 8-bit bus, but IDE was messed up because it replies on full 16-bit ISA bus.

Another thing, I personally would avoid to partition/format an old HD (< 528MB) on a modern PC without explicit LBA switch. Theoretically, LBA does not apply to a small HD < 0.5GB, but it's sometimes troublesome in my practices.

Just my two cents, your case may be totally different tho.

leeb
November 30th, 2013, 04:10 PM
found this

http://www.pcxt-micro.com/harddrive.html

good luck

leeb, your profile photo shows my first computer. Mine was a compact portable, and I had to use the program in dos to prepare the hard drive to boot from. I don't remember the name of the program.

Actually what you're seeing is a Tandy Model 4p... an 8-bit CP/M (z80) machine... my 'dinosaur' (and my favorite) :p

wesleyfurr
December 2nd, 2013, 04:35 PM
Many moons ago, back with 420Mb hard drives roamed the shelves at the local Wal-Mart, I bought one (a Conner) to install in the Tandy 3000HD that I had (a 286 machine). Fought with it for quite a while, and ultimately gave up and returned it. I never found any good reason why it shouldn't have worked...just assumed it was something in being that old of a machine...

Wesley