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freaktmp
September 3rd, 2012, 11:54 AM
I have an Apple Mac Classic with 4mb ram and the original 40mb hard disk, system 7.0.1 us freshly installed.

The superdrive works correctly, reading, writing and formatting. However I can't get it to mount floppy disks (show the floppy icon on the desktop).

I have tried booting the ROM system 6.0.3 and there it mounts floppy disks perfectly.

Bootable floppy disks also work fine.

The only way to get it to work with the 7.0.1 is to insert the disk before it shows the desktop (while it is displaying the "Welcome to Macintosh" banner). Then as soon its reaches the desktop, it shows the floppy icon and works fine, until I eject the disk. If I insert another disk after that (or the same disk for that matter) it does nothing.

I have tried a bunch of different disks, formatted them on the Mac, and on my PC, however nothing changes. I did a clean install of the operating system (previously it had 7.0.1.1 greek), no change. I tried copying the 6.0.3 from the rom to the hard disk and it works fine.

All these lead me to believe that this is a software problem, but I can't pinpoint it any further. I'm a PC techie, I know next to nothing about early macs.

The weird thing is it was working fine when I last tested it a few months before.

Any ideas?

RickNel
September 3rd, 2012, 09:46 PM
Have you tried the Disk Utility repair functions? Sometimes for no apparent reason a Mac will not recognise the identity of a disk until Disk Utility has "reviewed" it and stored the parameters somewhere...

I would also look for the Apple Hardware Test bootable disk image - downloadable free from apple.com. It needs to be the right one for the family to which your Mac belongs (if available). It might identify if you have a flaky controller or corrupted driver.

I'm assuming you are using disks formatted on the Classic itself? If not, there could be a minor disk alignment issue that is not affecting the boot sector but may be affecting the sectors needed for secondary mount. Just my guesses..

freaktmp
September 3rd, 2012, 11:51 PM
Is there a Disk Utility in System 7.0.1? The only thing I can find on the web is Disk First Aid, which I'll try as soon as I get home from work.

I can find no Apple Hardware Test for classic macs. I believe it must be only for newer machines.

As for your questions:
I have tried many different floppy disks, formatted on both the Mac and my PC. All of them work fine on the ROM System 6, on an HDD installed System 6, when bootable and if I insert the disk while System 7 is starting up (during the "Welcome to Macintosh" screen). However if I insert them after the operating system has finished booting, they are not recognized. I have tried two clean system 7 installations (using different versions, 7.0.1.1 greek and 7.0.1 US).

bibilit
September 4th, 2012, 03:12 AM
Hi,

I am thinking about a couple of things, the Superdrive has a couple of microswitches, maybe one is not working properly (stuck) and the floppy is not detected.

As you are getting a perfect mount with SSW 6.0.3, this is probably not the point, but who knows.

Have you tried a software to mount devices such as "mount everything" ?

http://www.overnet.de/hhp/mte/

last thing, hardware side again, those floppy drives need to be cleaned and re-greased to work properly .

RWallmow
September 4th, 2012, 05:01 AM
Is there a Disk Utility in System 7.0.1? The only thing I can find on the web is Disk First Aid, which I'll try as soon as I get home from work.

I can find no Apple Hardware Test for classic macs. I believe it must be only for newer machines.

As for your questions:
I have tried many different floppy disks, formatted on both the Mac and my PC. All of them work fine on the ROM System 6, on an HDD installed System 6, when bootable and if I insert the disk while System 7 is starting up (during the "Welcome to Macintosh" screen). However if I insert them after the operating system has finished booting, they are not recognized. I have tried two clean system 7 installations (using different versions, 7.0.1.1 greek and 7.0.1 US).

Classics quite frequently have bad/leaking capacitors on them, and I know that can cause the SWIM (floppy controller) to be unreliable, had odd quirky issues on my SE/30 with the floppy till I re-capped it. Doesn't quite explain why it works on 6 but not 7 though, unless 6 accesses the SWIM differently, in such a way that is unaffected by the bad caps, no idea :confused:

freaktmp
September 4th, 2012, 07:56 AM
The only thing I can find on the web is Disk First Aid, which I'll try as soon as I get home from work.

The insanity continues. I copied the disk first aid program on the hard disk. I insert a random floppy disk. As expected, no desktop icon. I run disk first aid, it recognizes the inserted floppy disk properly and then the floppy icon appears on the desktop! Everything works fine as long as disk first aid is running. As soon as I close it, no more icons on disk changes.

Any other ideas?


Classics quite frequently have bad/leaking capacitors on them, and I know that can cause the SWIM (floppy controller) to be unreliable, had odd quirky issues on my SE/30 with the floppy till I re-capped it.

Well it's definitely something I'll have to check out some time in the future. Thank you.

RWallmow
September 4th, 2012, 08:25 AM
...Well it's definitely something I'll have to check out some time in the future. Thank you.

USUALLY the caps are leaking out if they are bad, easy to spot in those cases, but they can be failing even without outward signs of failure, remember they are over 2 decades old now, well past their design "lifetime".

That said, its possible you could be looking at something else. Maybe some kind of virus. I am assuming you have tried many different disks to rule out possible flaky media. Cleaned drive heads to rule out contaminated heads (use cleaning disk, apple drives are VERY delicate, easy to destroy if you try to manually clean the heads). Just kind of grasping at straws here because what you have described is really odd, lol.

freaktmp
September 4th, 2012, 09:12 AM
USUALLY the caps are leaking out if they are bad, easy to spot in those cases, but they can be failing even without outward signs of failure, remember they are over 2 decades old now, well past their design "lifetime".

That said, its possible you could be looking at something else. Maybe some kind of virus. I am assuming you have tried many different disks to rule out possible flaky media. Cleaned drive heads to rule out contaminated heads (use cleaning disk, apple drives are VERY delicate, easy to destroy if you try to manually clean the heads). Just kind of grasping at straws here because what you have described is really odd, lol.

Well I am a PC tech and faulty capacitors is my bread and butter!

As for the other things you mention, do you know of a good antivirus for classic macs? I don't have a cleaning disk, I just bought one from ebay, I'll try it when it arrives. As for the media, the same media worked fine up to a few months ago and still work fine when autobooting and with system 6.

By god, if I find some spare time I'll post a video of this weirdness.

applefreak
September 6th, 2012, 04:47 AM
do you have a external bootable scsi drive ?

freaktmp
September 6th, 2012, 07:35 AM
No, no external devices whatsoever. No internal modification either. As far as I know this mac has never been opened, it's completely stock.