#Help!
40 messages in this thread
Michael,
"Plug and go" you say? I haven't stopped laughing (or is it crying?).
Didn't you forget parity, ARBT & test settings? Leave as is? How do big
hands get tiny little jumpers out and onto other teeny pins? I made a dumb
mistake and ordered terminator packs for the CD drive and he installed
them, only I can't figure out if the funny blue bars with pins coming out
of them are the terminators and can I just pull them out of the green card
that they are in which is in back of the 50 pin male (real pins) connector.
(OK, teckies, stop laughing).
Inside the case in was a ribbon cable with a 50 pin female connector (I
would call it centronics style) at either end (2 in all) and 2 50 pin black
plastic female connectors at intervals on the cable. I see the back of the
CD ROM drive & tape drive have 50 pin male plugs (real pins), a match I
guess. I imagine I can match up all the other cute plugs & receptacles <g>.
You said your ribbon cable had two 50 pin connectors at one and an Amiga
SCSI 25 pin connector at the other. They also sent a regular cable with a
50 pin (centronics style) male end and a 25 pin male (SCSI?) at the other.
I have the feeling these are wrong.
Do you punch out one of the the back indents so you can plug in cable? With
what, a sledge hammer? I guess girls like to know EXACTLY what they're
doing and boys like to take a chance.
\c/
via Coolwhap __|__ Gracia
Gracia:
Well, ARBT (arbitration) I kinda ignored until after I had the thing
installed… just left it alone. Test, does just what it says… if you
connect power to the drive, and throw the TEST switch to 'on', you can
INSERT A DISK, and EJECT A DISK to test the drive mechanism. In TEST mode,
I think that all control of the drive is LOCAL (ie: it won't respond to
software control via its connector).
If the drive is terminated, make sure that it is the last physical device
on the external chain, and that the tape drive (before it physically on
the scsi chain) is NOT terminated. I wish I could tell you how to remove
the termination resisitors on the drive, but I didn't order them. I always
planned on having the CDROM Drive BEFORE the terminated hard drive.
Now, as far as the cabling… is this thing hooking up to the external
scsi connector of an A3000? If so, you need a ribbon cable that has two
DB-50 pin female connectors (to hook up to each drive) and a DB-25 male
connector (to hook up to the external scsi port of the 3000). I just ran
the ribbon cable out the back of the case (over the edge). (at least I
think that's what I did… I'm sure I took the easiest route… and I'm
also pretty sure I didn't use a sledge hammer… I keep that in the
garage, and I don't recall goin down there anytime during the setup)
"I guess girls like to know EXACTLY what they're doing…"
Trust me. <ducking>
Michael,
Called Briwall, seems they have a new case with different ribbon cable so
it's a little less elegant, two cables instead of one and I'll have a
connector left over in case I daisy chain more toys.
Ya, John (the computer widower in my life <;^}>) says the case is just like
the electric boxes he put in the house, you knock out the slots you use.
Do you really pull the box apart to change jumpers and dip switches? Seems
like serious overkill. Gary told me how to take the terminator off. Any
more obvious and it would have bitten me.
I have the Tenex catalog, saw the GWiz ($40) ad. Probably smarter to just
order a Star 1000/Commodore ready ($120) and be done with it.
\c/
via Coolwhap __|__ Gracia
"Do you really pull the box apart to change jumpers and dip switches?"
Gracia:
Well, yes, and no. You only open up the case if you ever need to chnage
the settings. 😉 I haven't touched them since I set it up… and I
didn't close the case until I had it all going.
John is right… just tap the knockouts out with a screwdriver and
hammer… again, I didn't bother.
Be careful how the cables are set up… it will determine which drive
needs to be terminated. I had Briwall provide me with the specific cable
_I_ wanted…. one ribbon cable with two 50 scsi connectors and a DB25
connector to go to the external scsi connector of my 3000:
==1==……==2==…………………………++3++
where: … = 50 wire ribbon cable
1 = Outside 50 pin female scsi connector goes to the terminated
drive
2 = Inside 50 pin female scsi connector goes to the unterminated
drive
3 = Male DB25 scsi connector goes to the external scsi connector
Michael,
There is a IDC connector that connects to a fifty-pin ribbon and reduces it
to a 25 pin DB-25? (IDC = Insulation Displacement Connector) Gee, I wish I
had known about that one. Would make things easier. Never thought there was
such an animal in existence, but then again that doesn't mean anything.
cj
Chris:
That's what I have on my 50 wire scsi cable that plugs in to the external
DB25 scsi connector of the 3000.
Wow,
I'd like to find some of these IDC connectors. I did not know there was
such a beastie. I thought it was only a mythical creature that lurked
about in the minds of some men as only dreams can produce. [gawd who wrote
that?]
Mike, don't mind him, he doesn't get out enough. So this is a 50 pin IDC
to 25 pin DB25 connector eh? Have to talk to my supplier.
Oh, BTW, on another circuit. I've been trying to track down a supply of
the micro switches that are used in the standard Amiga mouse. These are
made by OMRON and I located them, and a Philadelphia distributor. The
standard switch is .30 each the more durable is .35 cents each and the
gold plated ones are 1.35 each. Now, they have a $30 dollar minimum order
limit. So, if you or anyone else want some of these switches I'd like to
know. I could order a hundred or so of the cheaper ones and mail a few to
whomever is in need of them for cost + S&H, unless you know where I can
get a dozen without paying a $30 minimum charge. They offered to send me a
few free samples, so I'll probably be happy fixing my two broken mice but
I know others would like to repair their broken mice. It is a real easy
fix, I've already cannibalized several older mice and at .30/.35 cents
plus postage it be worth it to have a ten or twelve laying in the parts
bin.
Chris
Chris:
I had Briwall build the cable for me (after I spent weeks looking in
catalogs for it, to no avail).
As far as the micro switches go, I wouldn't want to spend $30 for a couple
a hundred of the things, just so I could lose them in the clutter here
g>… maybe you could talk your dealer in to buying the $30 min order and
stocking the switches… then post a file in the libs describing where
people can find them. Personally, when a mouse dies, I bury it and get a
new one… typical consumer mentality I guess.
Michael,
Well, the switches are inexpensive, and the only real part that seems to
fail in the mouse. If enough members, (say 10) wanted a few, each of them
would only get eight switches, enough to repair the mouse four times. So if
eight to ten people ask me for them, I'll order the $30 of switches and
each member would probably pay around $3.50 each for eight switches. I
think this would include the postage. Unless, we go for the Gold Plated
contacts micro switch, then add around $1 per switch. Nothing wrong with
these mice, if you have one or two that aren't working and you don't intend
to fix them but just let them rot in some drawer, then send them to me,
I'll replace the switches and put them in another drawer or return them to
you.
cj
Michael,
We've bought those switches from DigiKey before. I think they have a
smaller minimum order. There are at least 3 different sizes in use though.
Probably more, but I've only seen 3.
That's interesting. Will, our Briwall sales rep said the cable came with
the case and they had changed cases. They say mine is a better set up, you
can daisy chain more cases and the cable has more play. That settled, how
do I hook up audio out? Radio Shack audio connecter? I won't have audio (I
have a 1950 monitor) till I get an amplifier for my AR speakers or
Commodore speakers.
\c/
via Coolwhap __|__ Gracia
Just a few tips:
Terminators:
The terminators will be little rectangular packages (2mmX3mmX20mm).
There will be three of them and they will be very near the 50 pin
connector on the PC (pee-cee) board (the 'green card' you referred to).
They SHOULD be in sockets, allowing you to remove them. You can pull them
out with a pair of needle nose pliers or a toothpick, or anything small &
pointy – just don't get too violent trying to pull them out :^)
Tips about wiring and figuring out which way to plug in the cable:
The terminators and cables must be plugged in the right way.
Fortunately, they've made it easy.
The flat ribbon cable should be marked on one edge with red or some other
color. This indicates PIN 1, and it should always be hooked up to the SCSI
device so that it is closest to the little '1' that should be painted on
one edge of the 50 pin connector on the CD-ROM (or whatever).
If there is no number painted near the connectors on the device, PIN 1 of
almost ALL device is usually indicated by a white square painted around
one of the pins. If this is not visible, check the solder holes on the PC
board itself themselves – PIN 1 is almost always a different shape than
the other.
The terminators will indicate PIN 1 by having a small dot painted near the
pin that should be plugged into the corresponding pin on the device.
Tips on cabling & termination:
Your Amiga probably has a 25-pin SCSI connector. So, you will need the
following:
A cable (25-pin male [DB-25 style] to 50 pin male [Centronics style]) to
hook up to your external box. (A 'Standard' Mac SCSI interface cable)
If your box is a PASS-THRU (ie: it has 2 connectors on the outside), then
you SHOULD NOT terminate either device internally. Instead, leave them
unterminated, and use an EXTERNAL SCSI terminator. This would be plugged
into the other connector (the one NOT plugged into your computer).
The reason for this is threefold; 1. You can then plug in another device
in-line without having to take apart the box and remove the terminators.
<continued>
Erik,
Thanks for all the tips. I want to be a hacker when I grow up <;^}>!!
Seriously, I saved your notes which shall go into my notebook of CI$
advice. I found the terminators on the CD ROM drive and took them off. The
"green card" was attached to the 50 pin connector, so I could just flip it
off and there was a 50 pin connector undernearth. I'm going to leave the
tape drive terminators on and just tape over the other 50 pin centronics
connector (keep it clean) rather than get an external terminator at this
time. It's all so easy when you know what is what and why.
The 50 pin ribbon connectors have a hump on one side which I take to be the
top since the drive connectors have slots to fit on top. How nice of them
to make some thing easy <g>.
Thanks again,
\c/
via Coolwhap __|__ Gracia
Don't tape over the ribbon connectors. The tape will likely as not leave a
residue that is harder to clean off than the dust that might accumulate.
Re the terminators the spec calls for termination at the ends of a chain
with no cable taps with more than a couple inches of cable each. That said
I have made some real kludges work. The main thing is find the longest
cable run and make sure there is a termination at each end of that as
close to the ends as practical. Side cables of up to a foot generally do
not hurt. Terminations within a foot of the real end do not generally hurt
if desperation hits. Experiment within these parameters and you should be
able to make things work fine. (Sometimes this experimentation is needed
because particular drives may not be supplying termination power and the
cable used to convert 25 pin Apple-Psuedo-SCSI to real 50 pin SCSI may not
have the termination power wire connected.
One last thing – for the external 25-50 adapter get one that is either
very short or that has 50 wires in the cable that narrow down to 25 at the
25 pin connector. A 3 or more foot long 25 pin cable is a sure path to
problems.
{@_@}
2. With two external connectors, you'll always be guessing trying to
figure out which one is 'furthest' from the terminators inside (and
TERMINATORS SHOULD ALWAYS BE AT THE END OF THE SCSI CHAIN). 3. The
external terminator will cover and protect the other unused connector, so
when you do try to use it, it wont be all covered in dust and grundge from
the back of your workspace (I know my machine gets dusty mighty fast!).
I just picked up an external terminator for $9.90 from Fry's in San Jose,
CA. If you pay more than $20 for one ,you've paid too much.
In closing, a comment about external cases:
(FOR HACKERS ONLY!!!!)
The CHEAPEST way to put a couple of SCSI devices into an external box is
to buy an empty micro/mini-PC case for $60-75 and then get some cabling.
I just put together an external case (4 bays, 200 Watt Power Supply) for
less than $100 – including case, external & internal cables, and external
terminator. This is FAR cheaper than I could have done by buying some
custom made SCSI-box, and includes a beefier power supply. As for size, by
the time you get a box to support 3 or more 1/2 height drives, they are as
big a a mini-PC case, and cost 3 times as much.
Anyway, hope this is of some use . . .
Erik Flom
Erik,
I found your comments helpful also… I've made a couple of SCSI
subsystems out of PC cases myself. What's your source for internal cables?
I found some, but they didn't match the alleged MAC SCSI cables we had.
The internal cables I got were just a legnth of ribbon cable with IDC
Centronics 50s on either end and 50 pin drive headers in the middle. I
couldn't figure out whether I ordered the wrong internal cable, or if the
MAC SCSI cables were really something else!
BTW, I've had one wierd problem with the power supplies in those external
cases. A 1 gig drive (5.25" full height) put some sort of unbalanced load
on the 230 watt supply. There wasn't enough load on the 5v for the supply
to regulate properly. I had to add a dummy load before the drive would
spin up.
Jim
Jim,
I don't mean to jump in here, but as far as having to put a dummy load
on the power supply to get the drive working:
I think most power supplies in PCs are switched-mode power supplies,
which basically means that they can be 'smart.' The power supply senses
that there is not a full load, and reduces its power output. I guess this
is supposed to prevent damage to the motherboard in a PC, but if the
motherboard is not drawing enough current, it probably is damaged
already.
I use an old PC case & power supply to house the HD for my bridgeboard.
At first, my drive would not spin up either, and I had to put an 18ohm 3
watt resistor across the 5v line to get my 12v line up to full voltage. I
just mounted the resistor to the metal case to act as a heat sink. It's
been working for me for about a year now.
Hope this sheds some light on it.
Warren Puziewicz
Warren, that's pretty much what I did… I had a old 5 ohm 25 watt
resistor in the junkbox. I bolted it to the case also & put a plug on it
so it can be removed when we install more drives & make up for the wierd
loading. The thing that puzzled me was that it worked fine with a smaller
drive alone, or with the smaller drive added to the load with the Gigabyte
drive.
Jim
W
On AutoPilot! (at last)
Warren,
Thanks for the clarification about Power Supplies!
Keep On Toastin'
Erik Flom
Close, Warren. The real reason is that PClone power supplies ONLY regulate
the +5. If there is not enough load on the +5, close to design load, the
supply may not have much "oomph" on the +12v line which powers the drive
motors and the seek "motors" be they servo motors (Seacrates) or voice
coils (good drives.) The load on the +5 helps make this work better. A
2amp or so load is generally sufficient to put the supply within its
normal operating range. (10 ohms 5 to 10 watts with proper derating.)
{@_@}
Jim, Glad to have been of some help . . .
I just went down to Fry's (a chain of electronic supermarkets here in the
SF Bay Area), and bought a 10' length of 50 conductor ribbon cable
($7.70), a 4 pack of IDC connectors ($4.29), 2 50 pin Centronics style
connectors ($4.50 each), 3' SCSI cable (25-50 pin) ($6.99), and an
external terminator ($9.99).
I cut off a few feet of ribbon cable, put a Centronics connector on each
end, put the 4 IDC connectors in the middle (spaced about 6-8" apart to
provide flexibility when moving connectors around – I hate it when you're
trying to pull out ONE connector, and the adjacent ones come free also
:^), and threw it in the case. The only thing I couldn't find was a couple
of metal backpanel holders, so mounting the centronics connectors was a
little tricky. Judicious use of my largest screwdriver as a pry bar
allowed me to wedge the connectors into 2 slots in the back of the PC case
– it seems to work for now.
The SCSI cables I have seen inside a number of Macs use the same 50 pin
flat ribbon cable and should not be any different from other SCSI cables.
The external cables are also interchangable, though I guess you can spend
more money and get specially shielded cables, or twisted pair cabling
which is even more expensive, but I've never had problems using the cheap
SCSI cables, and my SCSI chain is about 6-8' long now.
I've heard of problems about the power supplies in these units, but
fortunately, I haven't had any problem yet. There are a couple of
potential pitfalls there. Some supplies might need a load on the +12V to
operate properly, others use the sense line on the motherboard power
connector and will not turn on until it is driven high (I think :^), etc.
I've only got 2 3.5" Quantum drives in there now, but am planning on
adding a Syquest 88 & Tape Back-up unit later. Here's hoping they don't
cause problems.
Keep On Toastin'
Erik Flom
Thanks again Eric. Must be nice to have a place like Fry's handy. I
practically fainted when *the* local electronics outfit actually had a 50
pin IDC connector.:) It turns out that the original cables we thought were
MAC external SCSI cables were something else entirely. We got another one
in with a Floptical drive, which I used for reference. They didn't match
up at all. Oh well, that was the last of the 4 we had. I had been chopping
the 50 pin end & hard wiring it to a 50 pin header via a small board.
Ugly, but functional. It also makes a handy test jig around the shop.
The minitower cases we've used had DB25 knockouts on the back panel. Seems
like attacking a couple of those with a MotoTool & enlarging them to
Centronics 50 would work.
Jim
I finally convinced a co-worker to buy an Ami500! (Patting myself on the
backThe first question myendeared co-worker asked was 'what else, besides
my TV, can I hook this thing up to?' Anybody have any ideas on a CHEAP
moniter for her?
– GN
p.s. The keyword is CHEAP – it's how I got her to buy the Ami in the first
place!
Call Grapevine and Software Hut (phone #'s in back of AmigaWorld and
Amazing) for a refurb 1084… should be able to get it for something like
$199.
And watch the classifieds here in AmigaUser!
Thanx, I'll let her know.
-GN
The comments re: grinding out the DB-25 slots is a good suggestion, if
only I still had that old Dremel Moto-Tool I passed on to my parents! :^(
What do you think of the Floptical?
I've pretty much decided to get a Syquest 88MB cartridge ($479 w/ 1 cart –
internal), but the media cost is a deterrent. I found a place that sells
refurbished DAT drives for $750, so I was thinking of going for that
combo, and putting it in the case I have my other 2 drives in.
My problem, is that I need a large removable media drive that MAC users
will be able to handle, and the 88MB seems to be most common for the
graphic service bureaus in this area.
BTW, I don't know where you are located, but I lived in Reno,NV for a few
years, and when I moved into the bay area, it took me awhile to get used
to the concept of an 'electronics supermarket' – huge places with
everything all bagged and wrapped and ready to go, a row of cashiers like
you see in Target, and they stay open late on Friday's – YOW!
Too bad every city can't support this level of technological tinkering.
Then maybe we'd be more competitive!
Anyway, Keep On Toastin'
Erik Flom
Yeah, I've found the old Dremel to be quite handy in 'adjusting' things.
Amazingly enough, mine was a gift *from* my parents. 🙂
I only had the Floptical in the store for a couple days. The guy who
bought it decided to actually take it home. Anyway, I was favorably
impressed by the drive. It seemed fairly fast, like a slow HD instead of a
floppy. I did notice that it slowed down by a noticable amount during the
DOS format. The step time between cyl 2&3 was maybe 3 or 4 times faster
than between 750 & 751. It didn't seem to make significant impact when
copying files. I've always thought that the Floptical would be great for
Toasting… for the kind of renders I like to play with, one disk would
hold a day's worth of frames. I'd just have to change the disk once a day.
And it doubles as a backup media for HDs… On the other hand, I've
installed some Syquests too. They're a good drive as well. If the service
bureau wouldn't permit you to bring in your Floptical drive & hook it to
their system, the Syquest is probably the best choice.
I'm in Flint,MI, home of "Pets or Meat". We can get rabbits 24 hours a
day, but that's it. 🙂 The closest thing we have to a 'electronics
supermarket' is an Active Electronics outlet in the Detroit suburbs, about
70 miles away. The place I really miss was the junk store with all that
old military & old mainframe surplus.
Jim
Flint,MI, home of "Pets or Meat"…
Should that have been "Pets for Meat"? as in _Roger & Me_?
What a great American flick. I really want to see the sequel.
Michael,
I didn't know there was going to be a sequel to Roger & Me. Do you
know any details on it?
-Sean
Sean… only that it is done, and I thought it had been released.
Wish I could remember the title.
Hehe.. The title of the sequel was in fact, "Pets or Meat" (ie: you can
buy the rabbits alive or cleaned for the table). I watched it on PBS a few
weeks back.
– Keith
Michael,
I hate it when I can't remember what I was writing about when somebody
replies to something. My mother would say, "Well, it must not have been
very important." Ah, childhood memories…
-Sean
I think it was "Pets or Meat", the 'sequel' to Roger & Me. Didn't see it
myself, since it premiered on PBS the same night the local Fox station
runs Star Trek- The Next Generation. 🙂 My priorities are different. A
fair number of the local press thought the sequel was nothing but a ego
trip by Moore, since much of it was clips of his appearances on tv.
Thanks for the info on the Floptical.
Maybe the reason it took longer to format the higher tracks is that the
outer tracks might store more data – kinda' like a CLV laserdisc – it
would be an efficient way of increasing data storage. I don't know, and am
just guessing.
We have a bunch of surplus places around here, but they just aren't like
they used to be.
Keep On Toastin'
Erik Flom
I'm not sure how the Floptical stores it's data, so it might bump up the
clock rate & squeeze more data onto the longer outer tracks. But the
active area didn't seem big enough for the difference in radius to make a
difference. You can see the laser etched servo encoding on the bottom
surface of the disk. It's only about the middle two thirds of the disk.
.
Jim
I don't see the attraction in the Flopticals. 80 megs of Flopticals cost
$104, 88 megs of Syquest cost $109. 3 disk swaps for the same amount in
rendering data is a lot. Floptical disk prices will get cheaper but not
for 18-24 months, as will Syquest cartridges, sooner though.
So what's the big deal?
Well, Flopticals are only about $20 each. That comes out to about $1/meg.
The best I've seen on Syquest carts is $1.40/meg. Flopticals are more
rugged than Syquest carts. They're just like regular floppies. The Syquest
cart is a hard disk- the system uses flying heads just like a HD. And
unlike HD's it's not sealed against dust. So it's more prone to crashing
due to dust or mechanical problems. The floptical heads are already on the
disk, so they can't crash. The floptical disks are smaller also. Try
carrying a Syquest cart in your shirt pocket. 🙂 There's also talk that
the Floptical's media may be upgraded to 100+ megabytes within a year.