Adding a second floppy drive to an Apple IIe
Jeff Shanholtz
starting to get some software transferred over with ADTPro. I only had
a single floppy drive but recently came across a few drives that I
decided to try with my apple. I suspect that each one has a problem
because none of them seem to work as expected (one causes drive 1 to
spin but not boot, one causes drive 1 not to boot at all - immediately
goes to a command prompt, and one seemingly works but crashed ADTPro).
So I just want to confirm that there is no configuration I need to do
when adding a second drive, right? Just plug and boot? I don't see any
jumpers or anything.
Michael J. Mahon
Jeff Shanholtz
> That's right.
Thanks for the confirmation!
Linards Ticmanis
If you're using the old style Disk II drives which plug into the
controller card separately via 20 wite ribbon cables - before turning on
the power you have to make absolutely sure the plug is connected to the
card correctly, i.e. not moved a hole to the left or to the right so
that two pins don't enter the plug, or reversed so that the cable goes
towards the card instead of away from it, or sitting only on the front
row of pins. Otherwise it might indeed stop both drives from working,
even permanently if you're so "lucky". (For the newer drives with
daisy-chaining and a 19-pin SUB-D plug there isn't really much you can
do wrong, except inserting or removing plugs while the power is turned on.)
If that doesn't help, try replacing the 74LS125 (IIRC, but it's the only
74xx chip) on the analog board inside the drive. That one tends to burn
out very easily when a somebody plugs it in the wrong way, which might
have happened to the previous owner. Usually the other chips and the
controller cards survive undamaged.
--
Linards Ticmanis
Charlie
Only drive 1 on a controller is bootable.
Charlie
Linards Ticmanis
> controller card separately via 20 wite ribbon cables - before turning on
Should have been "wire", not "wite". Sorry.
--
Linards Ticmanis
Jeff Shanholtz
possibly going to buy one, so I will likely just give them back as
they are. I'm sure I plugged them in correctly though.
Michael J. Mahon
Old drives often have "mechanical" problems:
1. Off-speed--run speed adjusting program and adjust speed pot.
2. Dirty head--open and clean head carefully with alcohol.
3. Congealed seek cam grease--open, clean old grease, and
sparsely regrease with lithium grease. Also check head guides.
4. Hardened drive belt--open drive and inspect belt. Replace if
hardened, "exercise" it if it just has a "set". Speed may need
adjusting. (Occasional use prevents/cures some belt problems.)
-michael
NadaNet 3.1 for Apple II parallel computing!
Home page: http://home.comcast.net/~mjmahon/
"The wastebasket is our most important design
tool--and it's seriously underused."
Jeff Shanholtz
after all. 2 of the drives are off brand and 1 is apple so I'm hoping
to get the apple one working. It does spin up at boot time and I hear
the familiar booting sound coming from the drive, but at that point it
just spins without any hint of real activity (with a bootable disk in,
of course). Are there any troubleshooting guides available somewhere
to help me fix this? I do have hardware repair experience but I
wouldn't know where to start looking, and I'm guessing someone has
compiled a document somewhere about restoring these things.
These symptoms don't strike me as being explained by one of the
mechanical problems described by you, Michael, but if you disagree I
would be happy to crack her open and have a look.
I appreciate the advice!
schmidtd
> These symptoms don't strike me as being explained by one of the
> mechanical problems described by you, Michael, but if you disagree I
> would be happy to crack her open and have a look.
I think Linards has the key. At some point in the drives' lives,
someone may have plugged them in in the off-by-one pin configuration
and blown the 74LS125. Grab one or several of those chips, and open
'er up. The chips are socketed, so it's dirt simple to swap them
out. Boot noise but no action after that is typical of the chip
failure he mentioned. Oh, and if that really is the problem - then
all the disks you've tried in the drive so far have been effectively
erased.
I don't know of a maintenance manual, but I did a video showing
disassembly of the old-style Disk II for drive head cleaning:
http://www.youtube.com/watch?v=CMF3PL17kqg
Michael J. Mahon
> Well, I'm having second thoughts and may want to revive one of these
> after all. 2 of the drives are off brand and 1 is apple so I'm hoping
> to get the apple one working. It does spin up at boot time and I hear
> the familiar booting sound coming from the drive, but at that point it
> just spins without any hint of real activity (with a bootable disk in,
> of course). Are there any troubleshooting guides available somewhere
> to help me fix this? I do have hardware repair experience but I
> wouldn't know where to start looking, and I'm guessing someone has
> compiled a document somewhere about restoring these things.
>
> These symptoms don't strike me as being explained by one of the
> mechanical problems described by you, Michael, but if you disagree I
> would be happy to crack her open and have a look.
>
> I appreciate the advice!
Dave is right, a blown 74LS125 will disable the read channel (among
other things), and a drive that turns on and seeks, then just spins
(with a good bootable disk) is a sign of no read signal.
If it isn't the '125, it could be a dirty head, misalignment (not
likely unless a drive has been dropped), a bad analog board, or
a bad cable.
With a 'scope you can trace the read signal and see where it's
getting lost. Or you can swap known good components to isolate
the problem (always with some possible risk of damaging a good
component in the process).
Bill Garber
"Michael J. Mahon" <mjm...@aol.com> wrote in message news:u9mdnU2KU-U5xV_Q...@giganews.com...
> Jeff Shanholtz wrote:
>> Well, I'm having second thoughts and may want to revive one of these
>> after all. 2 of the drives are off brand and 1 is apple so I'm hoping
>> to get the apple one working. It does spin up at boot time and I hear
>> the familiar booting sound coming from the drive, but at that point it
>> just spins without any hint of real activity (with a bootable disk in,
>> of course). Are there any troubleshooting guides available somewhere
>> to help me fix this? I do have hardware repair experience but I
>> wouldn't know where to start looking, and I'm guessing someone has
>> compiled a document somewhere about restoring these things.
>>
>> These symptoms don't strike me as being explained by one of the
>> mechanical problems described by you, Michael, but if you disagree I
>> would be happy to crack her open and have a look.
>>
>> I appreciate the advice!
>
> Dave is right, a blown 74LS125 will disable the read channel (among
> other things), and a drive that turns on and seeks, then just spins
> (with a good bootable disk) is a sign of no read signal.
>
> If it isn't the '125, it could be a dirty head, misalignment (not
> likely unless a drive has been dropped), a bad analog board, or
> a bad cable.
Speed!!!!!!!!!!!! Off-speed will cause the same exact issue.
And speed is the easiest of all problems to check and fix. ;)
On Copy II Plus v9.1 there is a 'S-Drive Speed' checker under the
'Y-Verify' menu item. IIRC, it will tell you to put in a blank or
formatable disk, and if it is an Apple II Unidisk 5.25" drive, or
one that is compatible, you will find next to the front rubber foot
a small hole that you can access the speed pot thru with a jewelers
screwdriver. Gently turn it slowly one side to the other until the
program shows the speed within acceptable levels. I try to get it
right on, or one point high. All of my drives that I have set are
still good after years of service. I'm available via email if you
need help while you do this.
Bill
Linards Ticmanis
> Dave is right, a blown 74LS125 will disable the read channel (among
> other things), and a drive that turns on and seeks, then just spins
> (with a good bootable disk) is a sign of no read signal.
Especially if the drive "eats" disks (meaning it doesn't boot, and any
disk tried in it, even if it was write protected, won't even boot on any
other drive any more), the 74LS125 is the culprit with a close to 100%
chance.
So be certain not to insert any disks with valuable content into the
drive unless you have first excluded this failure mode (I found out the
hard way by losing an original game disk this way). The disks won't be
physically damaged, after the drive is repaired they can be re-formatted
without any problems, but their former content will be gone for good.
If it isn't the 74LS125, the ULA 2003 might be damaged, but that is far
less likely. I've yet to see a drive in which any of the other two chips
has failed.
--
Linards Ticmanis
Jeff Shanholtz
look at the drive today. I'm pretty sure the disk I used still works
so hopefully it's just the speed adjustment, but I'll have to double
check my disk!
Linards Ticmanis
> If it isn't the '125, it could be a dirty head, misalignment (not
> likely unless a drive has been dropped),
...or some unqualified person tried to align it with tools and/or
software that aren't up to the job, such as the ridiculous alignment
program on some CALL-A.P.P.L.E. disks. Hint: if you can help it, leave
the alignment alone, it's very easy to do more harm than good with that.
This might be too obvious, but check that the drive is actually spinning
the disk. Sometimes stiff, dry or broken belts can prevent that, or a
slipping belt can mean the disk is spinning far too slowly.
As for speed when the belt ISN'T slipping, I'd personally suggest not
using a special software to adjust it, but the strobe pattern on the
bottom of the drive mechanism. In case of the Disk II you'll have to
remove the bottom half of the case too (four more screws and careful
extraction of the cable), put in a disk, make the drive spin (e.g. by
trying to boot), then shine an AC fluorescent lamp on the bottom of the
mechanism, turning off all other lights if possible. If the speed is
right, one of the two patterns (which one depends on your mains
frequency, 50Hz or 60Hz) will seem to be standing still. On the disk II,
speed can be adjusted by the little screw that sticks out at the right
side of the smaller, vertical PCB inside the drive; but turn it in small
steps only, and do not try to adjust any of the other potentiometers and
trimmers inside the drive. If your mains frequency is reasonably stable
(which it is in most developed nations), the adjustment with the strobe
pattern is very exact, while some of the speed adjustment softwares are
a bit off because they used slightly wrong numbers for the Apple's
average clock rate. But the software solutions are still good enough for
everyday usage.
--
Linards Ticmanis
Jeff Shanholtz
copy ii+ speed check and with my working drive as drive 1 and this non-
working one as drive 2, drive 1 won't boot. It gives the standard boot
sound, but then just spins with none of the sound associated with
reading the disk. Drive 2 is preventing drive 1 from working, but if I
unplug drive 2, then drive 1 works fine. I also confirmed that the
disk is NOT being messed up by trying to boot it in this non-working
drive, so I suppose that means the logic chip isn't blown.
Out of spec drive speed wouldn't prevent the other drive from booting,
right? I wouldn't think any of the mentioned mechanical problems would
cause that. What would prevent the other drive from booting while also
not being stuck in write mode due to a bad 74125?
Bill Garber
"Jeff Shanholtz" <jeff...@shanholtz.com> wrote in message news:05
2f5fb1-702b-45aa-...@h36g2000pro.googlegroups.com...
> I haven't had a chance to open it up yet, but I was going to try
> the copy ii+ speed check and with my working drive as drive 1 and
> standard boot sound, but then just spins with none of the sound
> associated with reading the disk. Drive 2 is preventing drive 1
> from working, but if I unplug drive 2, then drive 1 works fine.
> I also confirmed that the disk is NOT being messed up by trying
> to boot it in this non-working drive, so I suppose that means the
> logic chip isn't blown.
>
> Out of spec drive speed wouldn't prevent the other drive from
> booting, right? I wouldn't think any of the mentioned mechanical
> problems would cause that. What would prevent the other drive
> from booting while also not being stuck in write mode due to a
> bad 74125?
Are these the non-Apple drives? Have you tried them without an
Apple drive connected? Perhaps you can provide more information
on these odd branded drives, and pictures even. Might I add that
it took me a good year of buying up and working on lots of drives
before getting pretty good at repairing them. This includes 3.5's,
and I still haven't seen them all. Some of them are just too rare
and the bids get really too high for me. Anyway, if you can't get
them to the right speed with the software, try the timing way.
Bill
Jeff Shanholtz
> Are these the non-Apple drives? Have you tried them without an
> Apple drive connected? Perhaps you can provide more information
> on these odd branded drives, and pictures even. Might I add that
> it took me a good year of buying up and working on lots of drives
> before getting pretty good at repairing them. This includes 3.5's,
> and I still haven't seen them all. Some of them are just too rare
> and the bids get really too high for me. Anyway, if you can't get
> them to the right speed with the software, try the timing way.
No, it's an apple drive. I'd much rather get the apple one working
than the other off brand ones. I can try the fluorescent light
approach (I think we have one somewhere), although I'm not convinced
that a mechanical (speed) issue would prevent the other functioning
drive from booting (i.e. a mechanical problem in 1 drive causing an
electronic problem on the drive card and/or other drive). Admittedly
I'm not very knowledgeable about these drives though.
Linards Ticmanis
The 74LS125 might still have failed partially, even if the drive doesn't
"eat" disks, so I wouldn't rule that out for now.
--
Linards Ticmanis
Linards Ticmanis
> No, it's an apple drive. I'd much rather get the apple one working
> than the other off brand ones. I can try the fluorescent light
> approach (I think we have one somewhere), although I'm not convinced
> that a mechanical (speed) issue would prevent the other functioning
> drive from booting (i.e. a mechanical problem in 1 drive causing an
> electronic problem on the drive card and/or other drive). Admittedly
> I'm not very knowledgeable about these drives though.
You're right, a speed issue wouldn't cause the other drive to fail. As I
said the 74LS125 is still a possible villain. The failure mode you
describe leads me to the assumption that the ULA 2003 might be more
likely in this case though; its failure could cause one drive to hold
the phase lines, so that the computer can't move the other drive's head
any more. Also, your controller card might have a problem with two
drives attached, or maybe your PSU might be failing and the two drives
tax it too much (the latter isn't all that likely though).
Do you maybe have another controller card, so that you can connect each
drive to its own controller?
Also try plugging in ONLY the supposedly bad drive, does it work then?
--
Linards Ticmanis
Jeff Shanholtz
> You're right, a speed issue wouldn't cause the other drive to fail. As I
> said the 74LS125 is still a possible villain. The failure mode you
> describe leads me to the assumption that the ULA 2003 might be more
> likely in this case though; its failure could cause one drive to hold
> the phase lines, so that the computer can't move the other drive's head
> any more. Also, your controller card might have a problem with two
> drives attached, or maybe your PSU might be failing and the two drives
> tax it too much (the latter isn't all that likely though).
>
> Do you maybe have another controller card, so that you can connect each
> drive to its own controller?
>
> Also try plugging in ONLY the supposedly bad drive, does it work then?
It doesn't work as the only drive in the system. Boot sound and then
spinning with no reading. So it sounds like one of the chips might be
the problem then. I appreciate the advice!
Michael J. Mahon
You're right, it wouldn't.
Michael J. Mahon
> On 05/05/2011 08:01 PM, Jeff Shanholtz wrote:
>
>> No, it's an apple drive. I'd much rather get the apple one working
>> than the other off brand ones. I can try the fluorescent light
>> approach (I think we have one somewhere), although I'm not convinced
>> that a mechanical (speed) issue would prevent the other functioning
>> drive from booting (i.e. a mechanical problem in 1 drive causing an
>> electronic problem on the drive card and/or other drive). Admittedly
>> I'm not very knowledgeable about these drives though.
>
> You're right, a speed issue wouldn't cause the other drive to fail. As I
> said the 74LS125 is still a possible villain. The failure mode you
> describe leads me to the assumption that the ULA 2003 might be more
> likely in this case though; its failure could cause one drive to hold
> the phase lines, so that the computer can't move the other drive's head
> any more. Also, your controller card might have a problem with two
> drives attached, or maybe your PSU might be failing and the two drives
> tax it too much (the latter isn't all that likely though).
Right--the deselected drive is all but powered down.
It would take a shorted 2003 input to interfere with another drive, which
seems unlikely.
(I'm responding as I'm reading this thread, so apologies for repeating what
others have said. ;-)
> Do you maybe have another controller card, so that you can connect each
> drive to its own controller?
>
> Also try plugging in ONLY the supposedly bad drive, does it work then?
--
Michael J. Mahon
> I haven't had a chance to open it up yet, but I was going to try the
> copy ii+ speed check and with my working drive as drive 1 and this non-
> working one as drive 2, drive 1 won't boot. It gives the standard boot
> sound, but then just spins with none of the sound associated with
> reading the disk. Drive 2 is preventing drive 1 from working, but if I
> unplug drive 2, then drive 1 works fine. I also confirmed that the
> disk is NOT being messed up by trying to boot it in this non-working
> drive, so I suppose that means the logic chip isn't blown.
Not necessarily--the chip can fail in ways that don't result in disk
erasure.
> Out of spec drive speed wouldn't prevent the other drive from booting,
> right? I wouldn't think any of the mentioned mechanical problems would
> cause that. What would prevent the other drive from booting while also
> not being stuck in write mode due to a bad 74125?
A failure in the read signal buffer or even the cable.
Michael J. Mahon
And if it's a belt-drive (most full-height drives), just spinning it up a
few times over a few days will often rejuvenate the belt enough to get it
to work. Then adjust speed and watch how much it varies--too much = new
belt.
Jeff Shanholtz
> It would take a shorted 2003 input to interfere with another drive, which
> seems unlikely.
That's exactly what is happening. It prevents my good drive from
reading when booting up. If I unplug the bad drive then the good drive
boots fine. So from your comment it sounds like the 2003, or the input
to the 2003, is the likely culprit. I'll look at that first. Thanks!
Michael J. Mahon
Actualy, check the '125 first. A shorted output there will kill
the read channel for all drives, and that's a likely failure mode
under the off-by-one connector scenario.
Also, be sure to check the disk cable. Insulation sometimes rubs off
of them and can lead to shorts with a myriad of symptoms.
Jeff Shanholtz
I'm going to check the cable next.
BTW, I opened up one of the non-apple drives, which is in a generic
looking enclosure with thin sheet metal. On first glance it looks like
the innards are apple. Did apple ever sell drives with thin sheet
metal or would this be an apple manufactured but rebranded drive?
Michael J. Mahon
If it's an Apple analog board, then someone probably "recased" it. ;-)
Otherwise, it's a clone. Apple published the schematics and also sold them
for more than 3x their cost, so cloning was inevitable.
Jeff Shanholtz
> If it's an Apple analog board, then someone probably "recased" it. ;-)
>
> Otherwise, it's a clone. Apple published the schematics and also sold them
> for more than 3x their cost, so cloning was inevitable.
It is an apple analog board. The interesting thing is the case is
EXACTLY like the "real" apple case as far as the venting and other
shape aspects other than the fact that the steel is about half as
thick as the "real" one.
As for the cable check, no luck. Swapping cables had no effect. So to
sum up, the drive spins but doesn't read when installed as the
solitary drive, and prevents a working drive from reading when
installed as drive 2. Swapping cables, 2003's and 74125's from my
working drive made no difference. Interestingly, the pseudo-apple
drive seems to have exactly the same characteristics and I tried
swapping all 3 good parts into it as well with no change. Seems both
drives might have the same issue, but I'm not sure I feel like
analyzing schematics at this point since I have a lot of other
projects that are higher priority. If someone has another thing to
check, I'll happily do so but otherwise I will probably give up and be
happy with the one drive I have.
I sure appreciate the input everyone has given.