HELP! - non-working disk drive, broken pin
Stephen F Felicetti
installation required connecting a jumper on the motherboard which tells
the computer a 2nd drive is connected. The jumper, however, was hidden
underneath the ribbon cable which connects the drives to the motherboard,
so I decided I should remove the ribbon cable from the board to facilitate
the connection of the jumper. Well, the ribbon cable connector proved
somewhat difficult to remove (I WAS careful to pull it STRAIGHT off), and
when it finally popped off, it took one of the pins off the motherboard
with it! I looked in HORROR at the broken connector on the board and told
myself I should NEVER have tried to remove the cable in the first place.
Well, I tried pushing the broken pin back into the vacant hole in the
plastic connector -- but it apparently wasn't making contact with anything.
I thought of removing the motherboard to solder the pin back into place, or
maybe just to solder a wire in its place, but I just wasn't prepared to
remove the entire board, and there is no way to get to the connection from
above the board -- its hidden beneath the plastic connector which surrounds
all the pins.
I finally looked at the schematics for the drive connector, but I couldn't
tell which pin on the schematic matched which pin on the board (they're
numbered in the schematic but not on the connector)!
If I could just find out the function of this particular pin, where it
goes and what it connects to, I could just hard-wire the respective wire
from the ribbon cable to its proper place, but my attempts to find out
where this pin goes have been futile! Can ANYONE out there help me?
The connector I'm referring to is just to the left of the power supply on
the 2000 (I have a B2000, revision 4.3 -- if that makes any difference).
It's labeled "CN303" on the board just below the connector.
The particular pin that broke off is the SECOND from the REAR of the computer,
in the LEFT column of pins (I think there are 24 pins in all).
Here's a diagram:
[REAR of computer]
+-----+
| . . |
| |
Broken Pin ----> | x . |
| |
| . . |
| |
| . . |
| |
| . . |
| |
_________
//_________ [connector actually longer]
CN303
[FRONT of computer]
I'd GREATLY appreciate if anyone knows the origins of this pin, knows
ANYTHING at all about this connector that might help, or has any better
ideas as to how to overcomethis problem and get my drive working (apart
from taking the whole machine away to be repaired and paying mucho dinero
to have someone rip out the motherboard and replace the whole connector)!
Thanks in advance.
P.S. - the first disk drive still works fine in spite of the missing pin --
apparently the pin has something to do with the second drive only(?)
-- Steve :-( Felicetti
Donald A Kassebaum
> I recently bought a 2nd internal drive (the A2010) for my 2000. The
> the connection of the jumper. Well, the ribbon cable connector proved
> somewhat difficult to remove (I WAS careful to pull it STRAIGHT off), and
> when it finally popped off, it took one of the pins off the motherboard
> with it!
> [REAR of computer]
> +-----+
> | . . |
> | |
> Broken Pin ----> | x . |
> | |
> | . . |
The schematics list pin 3 as a key. This is done to insure that the
connector can only be inserted one way. They cut the connector on
the motherboard and fill the connector on the cable. You DIDN'T
break anything. This make the cable installable only in one way.
They filled pin of the cable must be inserted over the blank pin 3
or else the they will not fit. It ok. You didn't break anything.
Go on and finsh installing your other drive.
Dak
George Robbins
> .... Well, the ribbon cable connector proved
> somewhat difficult to remove (I WAS careful to pull it STRAIGHT off), and
> when it finally popped off, it took one of the pins off the motherboard
> with it! I looked in HORROR at the broken connector on the board and told
> myself I should NEVER have tried to remove the cable in the first place.
This is most likely the one position that is used for "keying" the connector
so that you can't plug it in backwards and fry the floppy drive. Well
actually they don't fry, the just sort of spin continuously and zap any
disk you were silly enough to leave in...
Not to worry...
--
George Robbins - now working for, uucp: {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing arpa: cbmvax!g...@uunet.uu.net
Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)
John Mesiavech
Your disk drive is NOT, repeat NOT broken. Nor is your motherboard.
Calm down, that's right. Take a deep breath. Calmer now? Okay, onward...
Steve, the missing pin that you see on the disk drive connector is nothing
other than the pin referenced as *KEY on the A2000 schematics. Meaning,
it's supposed to be missing. The pin directly above it is pin 1, and is
where the red lead on the cable should go when you put it back.
Now, if you're still having trouble with your second drive (after placing the
jumper and replacing the drive cable), check the following:
1) Drive not accessing, or any disk put into drive shows up as NDOS:
Means you forgot to connect the power lead.
2) Drive light constantly on:
Means you have the ribbon cable on the back of the DRIVE plugged in
backwards. Reverse it and try again.
3) Both drive lights constantly on, or system refuses to recognize
EITHER drive:
Means that the drive jumpers are set wrong. If you have any documentation
on your drive itself, change the drive jumper to drive select 2; if
you don't know the proper jumper settings, don't play with 'em,
esp. on the earlier drives. You can make matters worse. Take it to
a reliable tech, and he'll take care of it for you.
John
(who's been putting B2000's together for a while now)
--
0-=-=-=-=-=-=-=-=-> All disclaimers apply; I didn't write this <-=-=-=-=-=-0
| ----------------------|------------------- |
| "I want a New Duck | John Mesiavech |
| One that won't try to bite | net.soldier.of.fortune |
| One that won't chew a hole in my socks | {backbone}!gryphon!jdm |
| One that won't Quack all night" | Go Purdue! (by req) |
| Weird Al Yankovic, "I Want a New Duck" | |
0-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-==-=-0
Bill Seymour
: I recently bought a 2nd internal drive (the A2010) for my 2000. The
: installation required connecting a jumper on the motherboard which tells
: underneath the ribbon cable which connects the drives to the motherboard,
: so I decided I should remove the ribbon cable from the board to facilitate
: somewhat difficult to remove (I WAS careful to pull it STRAIGHT off), and
: when it finally popped off, it took one of the pins off the motherboard
: with it! I looked in HORROR at the broken connector on the board and told
: myself I should NEVER have tried to remove the cable in the first place.
Luckly enough, there's no reason to panic. The missing pin is
actually just a key to make it so you can't accidently plug the cable
in backwards. Just put everything back to gether with the second drive
installed, and you should be OK.
:
: -- Steve :-( Felicetti
--
-Bill Seymour ...tektronix!reed!percival!agora!billsey
...tektronix!sequent!blowpig!billsey
Creative Microsystems Northwest Amiga Group At Home Sometimes
(503) 684-9300 (503) 656-7393 BBS (503) 640-0842
Brett Kuehner
> I recently bought a 2nd internal drive (the A2010) for my 2000. The
> installation required connecting a jumper on the motherboard which tells
> the computer a 2nd drive is connected. The jumper, however, was hidden
> underneath the ribbon cable which connects the drives to the motherboard,
> so I decided I should remove the ribbon cable from the board to facilitate
> the connection of the jumper. Well, the ribbon cable connector proved
> somewhat difficult to remove (I WAS careful to pull it STRAIGHT off), and
> when it finally popped off, it took one of the pins off the motherboard
> with it! I looked in HORROR at the broken connector on the board and told
> myself I should NEVER have tried to remove the cable in the first place
>
> -- Steve :-( Felicetti
I had the same thing happen to me, except that both of my drives still worked.
I suspected that the pin might be cut at the factory, to make it harder to
to connect the drive cable incorrectly. However, even though I could read
and write from both of the drives, one was always spinning and always had the
busy light on. Checking the schematics, it looks like the pin that broke on
mine (which I think is the same as in your diagram, I don't have my Amiga
handy at the moment) is a Drive Select pin. I managed to temporarily solve
the problem by pulling the broken stub of the pin out of the cable a bit,
and pressing the connector down very firmly. This has kept things normal
for the past 2 months, and through several long distance car trips, so
maybe I'm lucky, or maybe this wasn't the cause of my problem. It certainly
is easier to give it a try than to replace the entire connector (which would
seem to be virtually impossible, especially without screwing up other
things). If that doesn't work, you might be able to connect a jumper from
the trace on the board to the correct wire in the cable. In any case, good
luck.
Brett
--
Brett Kuehner
...!princeton!hhb!bvk
bvk%h...@princeton.EDU