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geoffm3
August 22nd, 2014, 05:50 AM
Okay, I'm not sure what's going on here exactly, so I figured I'd ask for some troubleshooting tips. I actually have a couple problems... one is that I'd really not like to install by floppy (since there's 20+ of them), but barring that I have the following problem:

I have an old 486 DX/2-66 with 8MB RAM, an Acer brand multi-IO VLB controller card (the whole shebang... CL video, serial, parallel, fdc, ide), and a 3COM Etherlink III card. I've got an IDE hard disk installed as master, and a CD-ROM drive installed as slave on the same controller (there's only one), and two floppy drives... a 3.5" HD and a 5.25 DD drive (A: and B: respectively). As far as I can tell, it looks like I can both read and write floppy disks correctly in Dos and Windows 95. It also seems to read floppy disk images that I've created on another computer (a Mac IIci). However, I have experienced issues both in Linux and also while trying to install OS/2 2.1. I have tried several fresh disks for the OS/2 install, but I always have problems reading the install, disk 1 and/or disk 2 (claims CRC errors) and I can get no further in the install. This seems to be random because it breaks at different times and on different disks. In Linux, I tried to use dd for creating disk images and got a few kernel messages to spit out about the disk controller.

It's strange because like I said, everything seems to be okay with Windows and DOS. The only thing I can think is that maybe my floppy drive itself is a little wonky and maybe there's some slight difference in step rate or something between DOS and the other OSes that's making it a bit unreliable. I need to see if I can scrounge up another floppy drive and try that I guess.

Stone
August 22nd, 2014, 06:45 AM
Have you got another floppy drive/machine that can read the Linux and OS/2 disks correctly? If not it's probably the disks, themselves. If you can read these OK on some other hardware then try cleaning the heads on the 486's floppy drive. If no joy, try another floppy drive, as you said.

geoffm3
August 22nd, 2014, 07:21 AM
Have you got another floppy drive/machine that can read the Linux and OS/2 disks correctly? If not it's probably the disks, themselves. If you can read these OK on some other hardware then try cleaning the heads on the 486's floppy drive. If no joy, try another floppy drive, as you said.

I thought it might have had something to do with the media, but I've got some near minty fresh HD disks that I'm using and still no dice. I think I've located another drive I can use so I'll probably try that next.

Stone
August 22nd, 2014, 08:33 AM
I thought it might have had something to do with the media, but I've got some near minty fresh HD disks that I'm using and still no dice.Floppy disks deteriorate with age. It really doesn't matter how many times they've been used, 0 or 100, when its time comes the disk's surface is no longer usable. They can (and have been) bad right out of a sealed box. Next, the drive's heads get fouled and need to be cleaned. It only takes one really bad disk one second to foul the heads. But if you try another drive and it reads them OK you will have eliminated the disks as the problem source.

krebizfan
August 22nd, 2014, 09:16 AM
If the floppy drive can read some disks but not others, the problem is likely not dirty heads (which would stop reading all disks) but faults in what is making the disks or a flawed controller chip. Cleaning heads may still be a good idea.

What exact error is the Linux system showing for dd? What chip is being used on the VLB card for the floppy controller? What model floppy drives? Unlikely, but someone might recognize a setup that is limited in supporting disks.

SomeGuy
August 22nd, 2014, 09:52 AM
I wouldn't rule out the possibility of a generally flaky drive or even floppy controller chip.

But first, I wouldn't trust the Linux dd command for writing floppy disks. It doesn't low-level format the disks or check for errors, or handle odd disk formats. I would recommend using a DOS based disk writer. And start each disk with a fresh unconditional format. Since OS/2 disks are FAT, you can run a disk utility like Norton Disk Test to verify that the disks are completely readable.

If the read errors only happen under OS/2, there is a good chance OS/2 specifically doesn't like your floppy controller chip.

3pcedev
August 22nd, 2014, 04:22 PM
I thought it might have had something to do with the media, but I've got some near minty fresh HD disks that I'm using and still no dice. I think I've located another drive I can use so I'll probably try that next.

I bought some almost brand new verbatim 3.5" discs about a month ago... half of them were faulty. Tried a different brand (Maxell) which were still new in box but about 8 yrs old and they all work perfectly.

k2x4b524[
August 22nd, 2014, 09:31 PM
He also states he has issues with linux and os/2. That leads me to believe the versions he is trying to use don't properly support that controller combo, whereas dos and windows 95 can.

As for floppy disk deteriorating, i've recently cracked open my Elephant SSSD disks, minty fresh, all format and hold data with no errors or nuttin :)

geoffm3
August 22nd, 2014, 09:52 PM
I wouldn't rule out the possibility of a generally flaky drive or even floppy controller chip.

But first, I wouldn't trust the Linux dd command for writing floppy disks. It doesn't low-level format the disks or check for errors, or handle odd disk formats. I would recommend using a DOS based disk writer. And start each disk with a fresh unconditional format. Since OS/2 disks are FAT, you can run a disk utility like Norton Disk Test to verify that the disks are completely readable.

If the read errors only happen under OS/2, there is a good chance OS/2 specifically doesn't like your floppy controller chip.

I'm suspecting that it might be the FDC as well. near as I can tell, the integrated controller must be a NEC 765 clone. I distinctly remember Linux spitting out some kernel messages complaining about the fdc, so it may well be something flaky and/or quirkiness that doesn't quite line up with a real 765. I feel pretty confident the drive itself is good, but who knows?

I haven't been able to locate a manual for the card.

Chuck(G)
August 23rd, 2014, 09:01 AM
If the controller works in DOS and Windows, it's not broken. A CRC error is diagnosed by the floppy controller itself.

Perchance is this a motherboard that already has a floppy controller onboard? I've seen some interesting muck-ups when Linux tries to handle the situation when 2 floppy controllers are present, with one disabled by the BIOS setup.

geoffm3
August 24th, 2014, 06:10 AM
If the controller works in DOS and Windows, it's not broken. A CRC error is diagnosed by the floppy controller itself.

Perchance is this a motherboard that already has a floppy controller onboard? I've seen some interesting muck-ups when Linux tries to handle the situation when 2 floppy controllers are present, with one disabled by the BIOS setup.


Nope, no built in IO of any sort (other than the keyboard of course) on this board.

geoffm3
September 8th, 2014, 11:04 AM
Okay, so I've replaced the floppy disk drive, and now it seems to be working... or rather the OS/2 2.1 install is failing in a different way. When I get part way into Disk 1 now, it errors out saying that country.sys is incorrect or somesuch. I poked around on google and found reports of people having similar issues installing using VirtualBox.

In my current installation, I'm using a 1.3gb hard disk with a dynamic drive overlay so that Win95 can access it all (Ontrack? Can't remember right now), and I've also got an IDE CD burner on the machine. Some people claimed that drives over 504MB and IDE CD-ROM drives can bonk the install process. I replaced both drives with a single 420MB drive and it made it past that point. I'm tempted to throw the bigger drive back on though and see if it behaves with that plugged in but the CD drive not and see what happens.

Stone
September 8th, 2014, 11:32 AM
DDOs can be the cause of all kinds of strange behavior. This is their major drawback.

RWallmow
September 9th, 2014, 03:58 AM
DDOs can be the cause of all kinds of strange behavior. This is their major drawback.

Ditto, I've had them mess up floppy access before on one machine, not sure why it messed with the floppy on that machine, but it did.

I ended up going with a IDE card with its own BIOS to overcome that PCs HD limitations, honestly that is probably the preferred method over a DDO, I would reserve DDOs for machines where a BIOS is not an option (laptops or desktops with all slots/rom sockets filled).