Unreadable disks -what's the cause?

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Unreadable disks -what's the cause?

Having had my Apple II+ clone in storage for a few decades I pulled it out and after some repairs have gotten it to work again.

But (almost) none of my floppy disks (5.25") work and I'm wondering if this is due to their age or if my disk drives need maintenance. What happens (after powering up or entering PR#6) is that the drive does its usual "ta-ta-ta-ta-ta" routine, but other than that I either get no further response, the computer gives me a "beep" and goes into machine code mode (monitor?) with an asterisk (*) or some disks load partly and drop into the monitor. Entering 6 followed by CTRL- P  usually reboots again.

 

So does this sound like disks that have just lost their magnetically stored data after all these years, or a problem with the drive(s)? Or the computer? Could it be the power supply? the +12V line is a little low (around 11.5V when booting, otherwise around 11.6V).

 

An irony is that just about the only disk I've gotten to work so far is the diagnostic program "Apple Cillin"! I was able to go through the various tests, so if the program is trustworthy at least my RAM, my 16K RAM-card in slot #0, ROMs, CPU and (according to the program) my disk drive as well (I've only had one attached for now though I have two) all works. I was also able to initialize a floppy, but in order to actually use it, don't I also have to put DOS 3.3 on it?

I never got around to understanding ProDOS (though there's some ProDOS stuff on some disks as well), but that's how I recall it -correct me if I'm wrong.

 

The next step of course is to find some way of downloading software on to my Mac and transferring them over to the II+. I've read through a whole lot of stuff on the subject (too much to take in) and believe that my Super Serial card will come in handy here, and together with a USB-serial adapter cable and ADTpro I should be able to do that. But I haven't bought a USB-serial adapter yet, and haven't learnt how to actually go through the process either. I also see that I have to re-learn a lot of the basics, like how to make a floppy disk ready, how to store files on it in DOS 3.3 and so on (at least I remember the "CATALOG" and "RUN filename"/"BRUN filename" commands) ;-)

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Try AsciiExpress site and make a disk

Hey there.  If you will go to http://asciiexpress.net then into the Disks section you will find a ton of games and other software you can download directly to your Apple II using nothing other than another computer, iPhone, iPad...really anything with a web browser and a headphone jack and a 3.5mm double ended "patch" cable - like you would use to play your iPhone in your car if it has the little input jack on the car stereo.  You connect the cable to your computer's Casette Input port (which might have the arrow pointing out instead of in on your Apple - not sure about your model but my IIe had confusing symbology and the out is really in and the in is really out as they are referencing the cassette instead of the computer.  50/50 chance and if wrong just swtich them.

 

Go to the site

Connect your cable - set volume to mid range

Boot the Apple, press control-reset or whatever your keystrokes are on your model to get to the ] prompt

Put a blank disk in your boot drive and close the door (can also be an old disk you want to re-use)

Type Load and hit return.  The Apple will sit there waiting

 

Then find a disk file you want to make from the site, tap it, then look at the "player" options to the right..

I always use the one called 8KFI Format - Format means you want the download to automatically format the disk in your drive, 8K is the slower download option but HIFI always seems to fail using my old iPhone 6 that I use only for this purpose and the 8K really just adds maybe 20 seconds to the process over HIFI which often fails for me.

Your Apple should BEEP, then Insta Disk will start, format the floppy, then the download will start writing to the newly formatted disk.  In about 2 minutes its done and you will have a prompt to hit Return to reboot, and voila, the newly created disk will boot into whatever you downloaded.

 

There is also a "Files" section on the site where you just download the game difrectly and play it without creating a disk.

 

Try that and see if it works

 

 

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When booting the apple dont use a disk

Cant figure out how to edit my post above, but to add one clarifying step...when you boot the Apple II to get to the LOAD prompt, dont use a DOS disk to boot it.  Just turn on the Apple and when the drives start to spin press Ctrl-Reset (thats my combo on the IIe) but yours might be different - whatever your strokes are to stop the disk attempting to boot and just get to the ] prompt is what you need to do.

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That's awesome! I will try

That's awesome! I will try that out before investing in the USB-serial interface.

 

I've gone through probably 60 or 70 disks, only to have a small handful more or less work. To my surprise though I had some CP/M disks which booted up perfectly! So now I got to test out my Z-80 card as well. Nice!

 

But something occured to me: having swapped drives 1 and 2 on the controller card I suddenly couldn't boot into the same disks that previously worked!

I can't remember all the DOS commands, but recall something along the lines of "S6,D2" for selecting drive 2, but booting is reserved ONLY for drive 1, right?

Anyway, this finding leads in the direction that there might be some calibration needed. I do have a basic (1 channel) mini-oscilloscope and a good digital multimeter. Where do I start to check if my drive(s) are up to spec and what do I need to do if they're mismatched/unaligned or have some other issues?

I figure that I should definitely not start by assuming my disks are (mostly) all useless and can just as well be erased (I do have some of my own files on them as well as stuff that can be replaced) but rather look into the hardware first....

 

 

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Too bad it's not possible to

Too bad it's not possible to edit postings here instead of creating a new posting...

I did some further research on the subject and came across the following:

 

Apple ][ FAQ: recalibrating Disk ][ drives

Apple ][ FAQ: adjustment of 5.25" floppy drive speed

Applebox: Disk ][ drive maintenance (part 1-4)

 

There's a LOT of technical info there which I see will take quite some time to get into (I have no idea where to start and don't want to mess things up beyond repair as I understand you can do if you mess with the adjustments before you understand it properly).

Some software was also mentioned in the above articles to aid in adjustment/maintenance:

 

Apple Disk Alignment Aid program part #652-0199 (.DSK file)

Locksmith 6.0 (.ZIP file) *

Datalife disk drive analyzer (.DSK file)

 

* There's a Locksmith folder at the above Asimov FTP site with numerous Locksmith versions (including multiple 6.0 versions as suggested to use in the Applebox Disk ][ drive maintenance website (see above for link). I'm not sure which one to use....

 

The problem is getting the software over to the II+ (from my Mac) without ADTpro and a USB-serial interface (and the abovementioned site with audio to Apple II tape input file transfers doesn't contain that software). Is there another method? Either another similar working site containing those programs, or a way to transfer the disk images I downloaded from the above links using the tape input method.

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Don't forget, dubiously

Don't forget, dubiously stored, and even some decently stored floppys grow mold on the surface.  Don't ask me what its growing on, but I've clagged my drive before to know its a thing.  I'd recommend cleaning the drive head initially.  If the floppys are marginal, and the head isn't pristine the two things together will become a problem.  The mold will be visible on the floppy surface as strange little blobs... it is possible to wash it off, but a right royal pain.

 

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Drive Swap

I ran into the same kind of issue when I swapped my drives but really just with 2 things...my old drive 1 wouldn't create disks reliably from the Asciiexpress site, but would boot my Sierra Space Quest disk and PFS write disk just fine as well as other disks like DOS.  I ran the speed test from CopyIIPlus and it showed me that that drive wasn't showing any kind of constant RPM but Drive 2 did.  So I swapped them and then neither of those commercial disks would boot on the other drive, but I could create disks from the site like mad.  So I started looking at the funky drive with the speed issues and one capacitor (C2) had a burned mark on it and wiggling it would make the drive spped up and slow down, etc. so I ordered a cap kit for it and replaced all the caps and it now works perfectly for both the site and with those old disks.  I recapped both drives just as a precaution and because of their age but then screwed up when I reconnected the 2nd drive (missed a row of pins) and fubar'd the LS125 chip so now Im waiting for it to come in to replace that, however my funky speed drive works great after adjust the speed to a steady 200 using only AppleCillian and COmputer Inspector - both of which ARE available on the DiskServer site - Apple-Cillian 2.0 is at the top of the disk list and Computer Inspector is under the MECC section so you have to look for it.  But you can make those two diagnostic disks from the site, but Locksmith isnt there.  You should get a 200 spped on Apple Cillian or close to it 198-202 is suppsoed a good range.  It has you put in a blank disk that can be erased when you go to run the speed test because it gets its speed by reading and writing to the disk so it tells you to remove the Apple Cillian disk before starting the test.  Anything out of that range means the spped needs adjusted.  If its fluctuating all over the place perhaps your cap has gone bad too.  If you get a steady reading but out of that range see below.

 

To adjust the speed itself, remove the housing from the drive(s) both top and bottom. The top cover just removesby sliding it backwards and off the cable, but the bottom one you can remove the screws and then gently turn it on its side without unclipping the cable which is clamped onto it. Once its on its side youll see the belt and pulley and stepper motor.  On the pulley is a 50 Hx and 60 Hz mark and lots of evenly spaced black squares.  Remember which section is which.  I don't have mine apart anymore so I forget if the inner is 50 and the outer is 60 or vice versa.  Now here is the tricky part.  With the drive on its side, boot the computer with the diagnostic disk, then get into that speed test program again and put in the blank disk again so the speed test starts.  Now using either an incandescent light or a fluorescent light (an LED bulb wont work for this) connected to a lamp shining towards the spinning label,  look at the rapidly spinning pulley with the marks on it.  If you are in the US you are most likely on a 60 Hertz power line so look at the set of spnning squares marked 60 Hz and see if they appear to be stable or are slightly drifting one way or the other.  Using the speed adjustment potentiometer (it will be top-up on the back speed control board) with a screwdriver, slowly turn the screw in or out until the blocks appear to be stable, then look at your screen to what the speed test is showing, then use that to further very slowly tweak the potentiometer until you get a steady 200 - which should also correlate to squares that are no longer moving in either direction.  If you are not in the US you might be on a 50 Hz power line so use whichever the 50 Hz circle of squares is.  The light test is handy for rough tuning and the Apple Cillian program onscreen is better for fine tuning.

 

Once the drive is at a perfect 200, reassemble at least the bottom panel and try your disks and see what happens.  While under there look at the belt and such too to make sure its not frayed and in the center of the pulleys and such too.

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Thanks for all your

Thanks for all your suggestions.

Actually, Apple-Cillin was one of the few working disks I had! And both drives appear to be OK when it comes to the speed check (they're very close to the centre and don't fluctuate much), but once I get to transfer files I should look further into this with some more specialized software for more detail.

 

For now  have yet to get cassette transfers working. I've got the Apple II input connected to my Mac headphone output and have tried all sorts of volumes, but nothing has worked so far with the site link you posted. In the end I opted for a shorter file with a game called "Air cars" (second entry from top) in the games section. I've also tried both "Hifi" and "Lofi" versions.

 

I understand that after the lead-in tone (4-5 seconds from start) I can expect one of three results:

  1. the Apple II gives a "beep" sound without anything appearing on the screen (indicating OK -the data is recognized so far)
  2. The Apple II gives a "beep" sound followed by "ERR" on the screen (indicating too high or low volume)
  3. The Apple II doesn't respond at all (not sure what this means but I'm guessing it doesn't "hear" anything and is still waiting for data)

 

What happens here is that once I've adjusted the volume (so I get a confirmation "beep" after a few seconds), then a few seconds later I get another "beep" followed by some machine code output. Specifically, this is what my screen shows after trying to transfer "Air cars":

 

]LOAD

BA06-     A=FE  X=FF  Y=A2  P=B5  S=F0

*

0800- 00 0B 08 01 00 8C 32 30

*

 

That's when I started looking into if there's an issue with the cassette interface. Lacking the knowledge of troubleshooting it properly I started by entering "SAVE" and listening to the cassette OUT. It worked but had an additional "clicking" sound, so I started exchanging ICs and found that swapping the 74LS74 (J13) fixed that (this diagram helped determine the function of the motherboard ICs). But could there be other hardware problems causing this? Could it be the EPROMs?

 

So then I looked into ADTpro and found out that there's actually an option for transferring files via the cassette interface! So I gave that go and the first and second transfer steps worked, but following the instructions I couldn't get to run ADT once transferred over ("800G" within the machine code prompt).

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Check the cable

I can say in my case, I had to find (luckily I had an old one hidden away in a box) an actual higher quality Monster patch cable.  I had a couple of the cheaper ones I used to use in my car and from a couple old PCs -the ones with the two green ends - and they would do what you are reporting...a beep followed by either an error or nothing at all.  Once I changed to the Monster cable it began to work perfectly.  The 8KFI always works on mine but I use an old iPhone 6 and have notifications and anything that could possibly interrupt it turned off as the old phone isnt even activated as a phone anymore but does have wifi and is on the iCloud so I would often get a notification or icloud text message in the middle of a transfer whicn of course would result in the ERR popping up and you'd have to reboot and start over.  My MBP running Catalina will NEVER work...not sure what kind of perhaps hidden audio signal its encoding that can't be heard by the ear, but it definitely has never worked from day one, but the old iPhone always does.

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Good suggestions, but I

Good suggestions, but I checked my connections on the II+ as well as the cable.

I have however made some progress! I've located my problems to be with the 16K RAM card as I've successfully transferred eDOS (via ADTpro) over to the computer. So now I have a working eDOS disk which, after booting into I was able to read several of the previously unreadeable disks with!

Next I used ADTpro to create an ADT disk on the II+, but alas its useless (as far as I understand) for actually transferring stuff with. I apparently need ProDOS and 64K for this. Correct me if I'm wrong.

So that's a great leap of progress! Next is troubleshooting the 16K RAM card so I can fully utilize ADTpro. Unfortunately I'm still not having any success with ASCII-express, but it may be the same thing as with your Mac. I'm using a Mac Pro with 10.9 Mavericks.

 

 

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