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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: spaceman88 on July 07, 2009, 11:59:25 PM

Title: 68 pin SCSI in Amiga
Post by: spaceman88 on July 07, 2009, 11:59:25 PM
Hi,
Will an Amiga work with a 68 pin SCSI hard drive (2.1 Gig, Seagate) if you use a 68 to 50 pin adaptor? A shop about 50 miles away is giving a couple away, if I go pick them up!
Title: Re: 68 pin SCSI in Amiga
Post by: Matt_H on July 08, 2009, 12:09:47 AM
Should be fine.
Title: Re: 68 pin SCSI in Amiga
Post by: spaceman88 on July 08, 2009, 01:25:07 AM
Quote from: Matt_H;514879
Should be fine.


Thanks, I thought it should be OK , but I never heard of an Amiga user doing it.
Len
Title: Re: 68 pin SCSI in Amiga
Post by: nishtek on July 08, 2009, 02:11:44 AM
Will work great.
Title: Re: 68 pin SCSI in Amiga
Post by: LoadWB on July 08, 2009, 06:16:37 AM
I've used a couple with Zip drives and CD-ROMs, worked fine.  But I cannot vouch for how well they work with hard drives.  I would assume that they should work fine, considering.

You might want to make sure you are using ones which terminate the unused lines.  I have used ones which I pulled from narrow tape drives installed in Dell servers with 68-pin SCSI, made by Datamate.  They work in both directions, too: I have one in a narrow SCSI controller in a Sun IPX Station running a Western Digital 9GB 68-pin drive.
Title: Re: 68 pin SCSI in Amiga
Post by: klx300r on July 08, 2009, 07:12:52 AM
yep..no problem!
Title: Re: 68 pin SCSI in Amiga
Post by: zipper on July 08, 2009, 10:37:06 AM
Using 3 of them; u160 and u320, no problems, SG and IBM 9 - 36 Gigs but on 68pin cable of CSPPC. Had also 50pin "SCSI3" with adapter on 68pin.
Title: Re: 68 pin SCSI in Amiga
Post by: orange on July 08, 2009, 11:52:21 AM
I had problems when using simple adapter. HDD didn't work, just like  LoadWB said.
Title: Re: 68 pin SCSI in Amiga
Post by: mdivancic on July 08, 2009, 12:56:39 PM
Quote from: orange;514937
I had problems when using simple adapter. HDD didn't work, just like  LoadWB said.


It will depend on the adapter and the hard drive. Simple adapters without termination require drives that have a jumper setting to switch them to narrow mode. On drives that have it the jumper is usually labeled SS or SW. I've got three large drives running using these $1 adapters, but some drives just don't work, even with the jumper set.

The more expensive adapters with termination should work with all drives, but I haven't tried one of these yet.
Title: Re: 68 pin SCSI in Amiga
Post by: save2600 on July 08, 2009, 01:38:42 PM
As Mikey said, not all 68-pin drives seem to work with the adapters. I know because I've tried about a half a dozen of them. I currently use a Quantum 16gb 68-pin with my 2060 card though with no problems. The better 50<>68 pin adapters have the termination you may need...
Title: Re: 68 pin SCSI in Amiga
Post by: ChaosLord on July 08, 2009, 01:48:22 PM
Any idea where I can buy one of these adapters that terminates the unused lines?
Title: Re: 68 pin SCSI in Amiga
Post by: save2600 on July 08, 2009, 06:02:21 PM
Having tried the Amiga specific haunts first, I couldn't find any. But ePay's got 'em:

...just type 'scsi adapter' and scroll down.

OR... http://discountechnology.com/80pin-68pin-50pin-SCSI-Adapter;jsessionid=0a01054f1f43d8808aca138b4e1d8781f848f09b5505.e3eTaxiNaN0Te34Pa38Ta38Ochn0#photos

http://discountechnology.com/80pin-to-50pin-SCSI-Adapter-Brand-New?sc=2&category=17
Title: Re: 68 pin SCSI in Amiga
Post by: Zac67 on July 08, 2009, 07:07:49 PM
It might be easier to switch to 68pin cabling incl. terminators and use adaptors for the 50pin devices which should be still be available, esp. when you're planning to add more than one wide device.
Title: Re: 68 pin SCSI in Amiga
Post by: orange on July 08, 2009, 08:00:32 PM
hm, would 68pin cable and terminator eliminate the need for 'advanced' adapter (or HDD with jumper)?
Title: Re: 68 pin SCSI in Amiga
Post by: Zac67 on July 08, 2009, 08:36:26 PM
Wide cable terminators are usually no problem to obtain and once the bus is terminated in whole there's no need for 'half-terminators' any more. You can also use built-in terminators on the end drives instead of cable terminators. OTOH most wide drives run fine on a narrow bus, there are few refusing to (esp. IBMs).
Title: Re: 68 pin SCSI in Amiga
Post by: amigadave on July 09, 2009, 08:34:46 AM
I have just recently purchased several 68pin & 80pin SCSI hdd's of 36GB & 74GB sizes to use as replacement drives for old failing and noisy 9.1GB full height hdd's, but I have been having a heck of a time getting the cabling and terminators set up right so the Toaster/Flyer Tools can see the drives, so they can be formatted to be used as Flyer drives.  Any help would be greatly appreciated.  I have adapters and all different kinds of terminators, but still no luck, even with LVD terminators when using LVD u320 drives.

Help!
Title: Re: 68 pin SCSI in Amiga
Post by: mdivancic on July 09, 2009, 12:17:36 PM
Quote from: Zac67;515021
Wide cable terminators are usually no problem to obtain and once the bus is terminated in whole there's no need for 'half-terminators' any more. You can also use built-in terminators on the end drives instead of cable terminators. OTOH most wide drives run fine on a narrow bus, there are few refusing to (esp. IBMs).


I've not been able to get any IBM drives to work yet here. I got a bunch of drives from work when we switched from SCSI to newer formats. I was only able to get about one in four to work.

Note: I get my adaptors from eBay.

Here's the one I'm using:

http://cgi.ebay.com/SCA-80-to-SCSI-1-2-3-68-50-Pin-Converter-Card-Adapter_W0QQitemZ310147836256QQcmdZViewItemQQptZPCA_Cables_Adapters?hash=item4836406960&_trksid=p3286.c0.m14&_trkparms=65%3A1%7C66%3A2%7C39%3A1%7C293%3A2%7C294%3A50

Found this with a quick ebay search for SCSI Adaptor.
Title: Re: 68 pin SCSI in Amiga
Post by: Zac67 on July 09, 2009, 06:36:10 PM
Those are simple SCA adaptors, so any drive requiring full termination won't work.
When you can put the SCA drive at the chain end there's a trick: simply plug a wide terminator into the spare 68pin connector. That way the drive sees full termination and cooperates.

@amigadave
You can't use "LVD" terminators on an Amiga - there's no U2W+ controller supporting it. "LVD/SE" or "SE" or unlabeled terminators do work however. Amiga controllers are pre-Fast/Async or Fast (most), Ultra (few) or UltraWide (some late accelerators) but they're all single ended.
Title: Re: 68 pin SCSI in Amiga
Post by: amigadave on July 10, 2009, 04:04:17 AM
Quote from: mdivancic;515079
Note: I get my adaptors from eBay.

Here's the one I'm using:

http://cgi.ebay.com/SCA-80-to-SCSI-1-2-3-68-50-Pin-Converter-Card-Adapter_W0QQitemZ310147836256QQcmdZViewItemQQptZPCA_Cables_Adapters?hash=item4836406960&_trksid=p3286.c0.m14&_trkparms=65%3A1%7C66%3A2%7C39%3A1%7C293%3A2%7C294%3A50

I have the same adapter and have been able to get some 4GB hdd's to work on a Warp Engine 040 accelerator SCSI-2 controllers.  I can't seem to get it to work on my CSPPC SCSI-2 wide controller, or the Flyer 50pin SCSI controllers.  I have tried all types of termination, both LVD/SE and non-LVD active terminators.  Still no luck.

I now have 3x 73GB 80pin SCA hdd's and 3x 36GB 68pin U320 hdd's plus 1x 73GB 68pin U320 hdd and have yet been able to get any of these large hdd's recognized on any of my SCSI controllers using both 50pin or 68pin cables and all types of terminators and jumper combinations on the drives themselves.

I am really stumped as to why I am having so much trouble and see now why some other members have cursed so loudly about having SCSI configuration problems.  This is my first experience with such difficulty in getting SCSI drives working.

@Zac67,

The drives and terminators I am trying to use are all marked LVD/SE and I have enabled the SE jumpers on the drives.  The first terminators I tried did not have the LVD/SE designation written on them, so I ordered and received and tried the LVD/SE terminators and have seen no difference.

Very frustrating!
Title: Re: 68 pin SCSI in Amiga
Post by: save2600 on July 10, 2009, 02:44:20 PM
I'd like to mirror what AmigaDave and mdivancic have said and are experiencing. I too inherited a combination of IBM and Seagate drives from an old Dell server. Out of 4, I was only able to get ONE to ever work! And I've got the adapters w/ termination everyone else is talking about. I chalked it up to bad drives (I kept them all anyway), but am somewhat "relieved" to hear others have experienced the same things. I am currently using the working 16gb Seagate drive in my A2500 with zero problems however. When SCSI works, it works real well  :-)

But I guess my next question is: why is SCSI so seemingly picky or flaky? Combination of things I guess - but frustrating when you know how to troubleshoot, but are left with no real answers.
Title: Re: 68 pin SCSI in Amiga
Post by: spaceman88 on July 10, 2009, 11:06:02 PM
Quote from: spaceman88;514877
Hi,
Will an Amiga work with a 68 pin SCSI hard drive (2.1 Gig, Seagate) if you use a 68 to 50 pin adaptor? A shop about 50 miles away is giving a couple away, if I go pick them up!


Ok, I picked up the drives. I downloaded the new(er) HDtoolbox, when I run it this is what it says.... "Compaq   ST32171w     0940     unsupported" and all the buttons are grayed out.
If I use the 3.1 install disk it usually locks up when scanning for drives, but once it got to the partitioning stage and I think it was asking me to enter data like # of cylinders, size , sectors etc. It seemed to think I had a 20meg hard disk. Is there any other software I can use that might support it? Also I'm using a 2091 rev. 6.6 card that is working with a Quantum drive (40meg), would it make difference if I used a GVP, ICD or Fastlane card?
Len
Title: Re: 68 pin SCSI in Amiga
Post by: spaceman88 on July 12, 2009, 02:27:15 AM
Ok,
I tried the GVP faaastprep program. Unfortunatly all it says is "Can't open GVPSCSI.device", the file is in the Expansion drawer.
Title: Re: 68 pin SCSI in Amiga
Post by: RiP on October 08, 2017, 06:16:40 PM
My GVP A2000-HC+8 doesn't detect Hitachi 73GB SCSI 68pin :(
I used SCSI 68 Male to IDC 50 Male Adapter. I enabled TP/Force SE but they didn't help.
Title: Re: 68 pin SCSI in Amiga
Post by: BozzerBigD on October 08, 2017, 07:58:31 PM
Weird as it should work fine! Have you checked the jumpers? Unit ID, termination, etc
Title: Re: 68 pin SCSI in Amiga
Post by: QuikSanz on October 08, 2017, 08:04:29 PM
Quote from: spaceman88;515397
Ok,
I tried the GVP faaastprep program. Unfortunatly all it says is "Can't open GVPSCSI.device", the file is in the Expansion drawer.


If using OS3.1 throw faastprep in the bin, useless!
Title: Re: 68 pin SCSI in Amiga
Post by: RiP on October 08, 2017, 09:26:07 PM
Quote from: BozzerBigD;831474
Weird as it should work fine! Have you checked the jumpers? Unit ID, termination, etc


Yes, enabled termination power, different ID and Force Single End jumpers but no luck.
Title: Re: 68 pin SCSI in Amiga
Post by: Oldsmobile_Mike on October 08, 2017, 11:52:06 PM
Quote from: QuikSanz;831475
If using OS3.1 throw faastprep in the bin, useless!

+1
Title: Re: 68 pin SCSI in Amiga
Post by: BLTCON0 on October 09, 2017, 04:34:03 PM
Quote from: RiP;831469
My GVP A2000-HC+8 doesn't detect Hitachi 73GB SCSI 68pin :(
I used SCSI 68 Male to IDC 50 Male Adapter. I enabled TP/Force SE but they didn't help.

Since it has a "force SE" jumper (force Single-Ended mode) it means it's an LVD (low voltage differential) drive.
These drives never have onboard termination. The "termination power" jumper is just to provide power to a standalone terminator, plugged at the end of the cable.
This also brings another implication into play:

Wide-SCSI bus (= 68 pin = 16 bit) is conceived as an extension to the older narrow-SCSI bus (=50 pin = 8 bit) standard. Actually, commands are still transferred in 8-bit 5 MHz async mode, regardless of advertised bus speed. The wide transfers (16 bit) or faster transfers (10 mhz Fast, 20 Mhz Ultra) are purely for data transfers.

So a 16-bit bus is more or less an 8 + 8 bit bus, with a low-byte (corresponding to operation in 50 pin narrow SCSI mode) and a high-byte (used in 68-pin wide SCSI mode).

Most 68-pin drives do require the presence of so-called bias-voltage on ALL the scsi lines (both low byte and high byte ones) in order to successfully init. This means that when in narrow mode, they require a special 50-68 adapter with high-byte active termination, which (as a side effect) will provide said bias voltage (assuming Termination Power exists, of course, but this can be set).

Alternatively, in lack of such an adapter, one can place the 68-pin drive with a simple (passive) 68-50 adapter LAST in the chain and enable its onboard terminator, which will have an identical side-effect.

Unfortunately, LVD drives by design don't have onboard termination, so this trick can't be used in your case. Using a wide active external terminator will not have the desired effect. Your safest bet is a (more expensive) high-byte terminated 68-50 adapter, plus (of course) active 50-pin terminators at both ends of the controller's 8-bit bus, with the drive (again of course) in SE mode.

Seagate wide drives were a distinguished exception - they universally worked fine in narrow mode, without requiring bias-voltage.
Title: Re: 68 pin SCSI in Amiga
Post by: LoadWB on October 09, 2017, 04:43:41 PM
Quote from: BLTCON0;831508
You'll need to shed for an expensive high-byte terminated 68-50 adapter.

They're not really that expensive.  The Datamate 5000-5068-13 can be found relatively cheaply and has high-byte termination.  I first found these in Dells with UW-SCSI adapters and narrow tape drives.  Bought several of them a while back just to have on-hand (one of which I just demolished to prove the high-byte resistors are actually present.)

Check here:

https://ebay.com/itm/222653979494

It's more than I paid for mine but still not a bad price.
Title: Re: 68 pin SCSI in Amiga
Post by: BLTCON0 on October 09, 2017, 04:49:29 PM
@LoadWB
Yes indeed, back in the day (when I was all about SCSI) they were about 3x the price of regular ones, so indeed they aren't 'expensive' but just 'more expensive'.
I actually corrected it right away but you posted faster than your shadow :-)

Furthermore, as today SCSI is mostly gone, I guess they can occasionally be found dirt-cheap as stock surplus or whatever - the culprit (most often) being with the seller unable to distinguish between passive and terminated ones.
Title: Re: 68 pin SCSI in Amiga
Post by: zipper on October 09, 2017, 06:02:15 PM
Quote from: BLTCON0;831508
Seagate wide drives were a distinguished exception - they universally worked fine in narrow mode, without requiring bias-voltage.

Yes, my 68pin SG had built in termination available so I could use it on the other end in my CSPPC SCSI cable as terminator, the other end needed an active terminator.
Title: Re: 68 pin SCSI in Amiga
Post by: LoadWB on October 09, 2017, 08:18:03 PM
Quote from: BLTCON0;831510
@LoadWB
Yes indeed, back in the day (when I was all about SCSI) they were about 3x the price of regular ones, so indeed they aren't 'expensive' but just 'more expensive'.
I actually corrected it right away but you posted faster than your shadow :-)

Furthermore, as today SCSI is mostly gone, I guess they can occasionally be found dirt-cheap as stock surplus or whatever - the culprit (most often) being with the seller unable to distinguish between passive and terminated ones.


Right, these adapters and bloody S-Video to composite adapters, as well.  Flushed $20 on 10 of them only to find they're completely wire-through.  (That's a whole other thread and topic, though.)

If you want a good laugh, and some reputable outlets are guilty of this shyt, too, go look up things like USB-to-Firewire or HDMI-to-component adapters.  Read the small print and you'll find these are completely wired-through, not a circuit in the mix to do any actual conversion.

Back on topic, yes, I found that both Segate and IBM LVD-SCSI drives are great in whatever system you throw them in.  Most of the time even if you don't set the jumper for SE they'll still work just fine.  That's a big bonus for those who don't know any better (hey, we all start somewhere!) and those who just start over-looking simple things (hey, we all end up somewhere!)

:D
Title: Re: 68 pin SCSI in Amiga
Post by: BLTCON0 on October 10, 2017, 02:22:36 PM
@LoadWB
Very true. Which brings forward a terminology issue/dilemma, too.

My preferred usage would be "adapter" when only the connector's physical format is changed, but the physical (electrical) protocol/signalling remains mostly unchanged (mild alterations such as voltage level conversion wouldn't the "adapter" concept).
Otherwise it would be "converter".

If such a clear distinction was universally adopted and followed, there would be no confusion.

For example, if someone sold a USB-to-PS2 *adapter*, it would be implied that it's just wire-through and the protocol conversion (or selection) is deferred to the device (e.g. a keyboard or mouse in this case).
Same for S-Video to Composite, HDMI-to-VGA etc adapters (where a subset of the S-video / HDMI connector pins must alter -if supported by the graphics hardware- their protocol/signalling significance at the root level, so only a passive wire-through "adapter" is then needed).

If on the other hand it was sold as a USB-to-PS2 *converter* it would be implied it's an active device meant to convert from a specific protocol into another specific protocol.

But as nothing is explicitly set in stone, the terms are more often than not interchangeable and confusion prevails.
Title: Re: 68 pin SCSI in Amiga
Post by: RiP on October 20, 2017, 02:58:38 PM
Well, the adapter didn't work with Adaptec SCSI card too:
https://www.amazon.com/Monoprice-100077-SCSI-HPDB-Adapter/dp/B001TIQ8G2

I'll try to find this next time:
https://www.aliexpress.com/item/SCSI-SCA-80-Pin-To-SCSI-68-Pin-IDC-50-Pin-Adapter-SCSI-80-68-50/293779398.html
Title: Re: 68 pin SCSI in Amiga
Post by: Chucky on October 20, 2017, 04:47:32 PM
Quote from: spaceman88;514884
Thanks, I thought it should be OK , but I never heard of an Amiga user doing it.
Len


CSPPC??  I use Wide scsi on my A4000.
sure using a -> IDE adapter and SSD disk    but stll wide (68pin)

31MB/sec:)
Title: Re: 68 pin SCSI in Amiga
Post by: BLTCON0 on October 20, 2017, 06:42:17 PM
Quote from: RiP;831981
Well, the adapter didn't work with Adaptec SCSI card too:
https://www.amazon.com/Monoprice-100077-SCSI-HPDB-Adapter/dp/B001TIQ8G2

That's a passive adapter. No good for your case as I already wrote.

Quote
I'll try to find this next time:
https://www.aliexpress.com/item/SCSI-SCA-80-Pin-To-SCSI-68-Pin-IDC-50-Pin-Adapter-SCSI-80-68-50/293779398.html

Why would you do that? You said your drive is an 68-pin one, not an SCA 80-pin one. Even if you had a SCA drive, the story wouldn't end with this adapter.

For your setup, ideally you should desolder the onboard passive terminator of the GVP card and use dedicated 50-pin *active* terminators at both ends of the cable. It should look like this:

{IDC1}Term1-----{IDC2}GVP 50pin-----......--------{IDC3}[high-byte adapter + your LVD drive]----{IDC4}Term2

- Term1, Term2 are something like this (https://www.cablesdirect.co.uk/data-cables-adapters-c498/adapters-c505/scsi-terminators-adapters-c527/scsi-2-50-pin-idc-male-active-terminator-p2594).
- The high-byte terminating adapter is something like this (https://www.ramelectronics.net/sm058.aspx).
-So you need a cable with 4 50-pin IDC (female) connectors.
IDC1 is where Term1 gets plugged.
IDC2 connects to GVP's onboard 50-pin header
IDC3 connects to the 50-pin outlet of the 50-68 high-byte adapter (the 68-pin outlet connects to your LVD SCSI drive itself, the drive must have TP enabled and must be set for SE mode)
IDC4 is where Term2 gets plugged
-Cable segment between IDC1 and IDC2 must be short, the same for IDC3 to IDC4 (about 5 cm). IDC2 to IDC3 length doesn't matter much (well, it still shouldn't exceed 1.5m)
Good custom cables here (http://www.cs-electronics.com/50-pin-internal-scsi-cables/).

Remember to set TP (this will provide the necessary power for the standalone active terminators Term1 and Term2) and to force SE just in case the drive doesn't autoconfigure itself in SE mode.

If you decide to skip desoldering the onboard passive terminator of the GVP card, then you only need your cable to match the IDC2-IDC3-IDC4 configuration, and of course you skip using Term1. I'm not actually advising against this configuration, it should still work OK.

That's about it.
Title: Re: 68 pin SCSI in Amiga
Post by: RiP on October 21, 2017, 09:03:39 AM
Quote from: BLTCON0;831987
If you decide to skip desoldering the onboard passive terminator of the GVP card, then you only need your cable to match the IDC2-IDC3-IDC4 configuration, and of course you skip using Term1. I'm not actually advising against this configuration, it should still work OK.

That's about it.


Well, my 68pin SCSI hard disk doesn't have TE but TP.
Then I tried this configuration but GVP/Adaptec didn't detect the 68pin SCSI hard disk:

{IDC1}GVP 50pin-----{IDC2}[high-byte adapter+my LVD drive]----{IDC3}50pin SCSI 4GB HDD+TE jumper enabled (I used it since I didn't have 50pin Termination)